ORCID Profile
0000-0003-1244-4277
Current Organisations
Monash University
,
Monash Health
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Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Robotics And Mechatronics | Manufacturing Engineering | Mechanical Engineering | Manufacturing Engineering Not Elsewhere Classified | Precision Engineering | Manufacturing Robotics and Mechatronics (excl. Automotive Mechatronics) | Automation and Control Engineering | Simulation And Modelling | Nanotechnology | Biomedical Engineering | Artificial Intelligence and Image Processing | Interdisciplinary Engineering Not Elsewhere Classified | Mechanical Engineering | Biomedical Engineering Not Elsewhere Classified | Interdisciplinary Engineering |
ANZSRC Socio-Economic Objective (SEO)
Medical instrumentation | Machinery and equipment not elsewhere classified | Scientific instrumentation | Industrial instrumentation | Medical Instruments | Special education | Surgical Methods and Procedures | Surgical methods and procedures | Expanding Knowledge in the Physical Sciences | Industrial Machinery and Equipment | Scientific Instruments
Related Links
Publications
Predictors of Surgery After Percutaneous Mitral Valvuloplasty
Publisher: Elsevier BV
Date: 09-2006
DOI: 10.1016/J.ATHORACSUR.2006.03.096
Abstract: Percutaneous mitral valvuloplasty (PMV) is a minimally invasive treatment option for selected patients with mitral stenosis (MS). In general, the procedure is well-tolerated with a high success rate. However, relatively little is known about the predictors of surgical intervention after PMV. A retrospective analysis was performed on 243 patients undergoing PMV at a single institution over a 14 year period. Fifty (21%) of 243 patients, comprising 44 women and 6 men and aged 55 +/- 14 years, underwent cardiac surgery at a median interval of 6 months (range, 0 to 130) after PMV. Nine (18%) underwent a procedure within 15 days, and 41 (82%) had a procedure more than 15 days after the valvuloplasty. After PMV, surgery-free survival was 85% at 1 year, 83% at 2 years, 81% at 3 years, 80% at 4 years, and 80% at 5 years. The need for surgery after PMV is not uncommon. Independent predictors of surgery after PMV included severity of mitral regurgitation (p < 0.003) and a higher echo score (p < 0.039).
An autowave based methodology for deformable object simulation
Publisher: Elsevier BV
Date: 07-2006
Towards a statewide Cardiac surgery database: The Victorian initiative
Publisher: Elsevier BV
Date: 2001
DOI: 10.1046/J.1444-2892.2001.00072.X
Abstract: The establishment of the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) at the beginning of the 1990s gave rise to an early proposal for the development of a cardiac surgical database. The Victorian Government gave its in-principle backing to a statewide database project from late 1997. Release of a promised dollar 200,000 grant for development was contingent on the ASCTS being able to fulfil several initial requirements. These were: (i) the provision of an indicative annual report outlining performance against a series of clinical indicators (ii) an indicative peer-review process and (iii) the addressing of issues surrounding intellectual property and ownership of any database that was developed. In outlining a strategy to be used in developing and implementing the project plan, it was determined by the project development team that all Victorian cardiac surgical units were, in fact, collecting similar data, but were using different software and analytical tools. The Cardiovascular Disease Prevention Unit at the Baker Medical Research Institute in Melbourne has developed a model of mortality and risk-adjusted complications out of the pooled Victorian data. This, it is hoped, will be a forerunner of a major achievement in the monitoring of cardiac surgery procedures nationally, and the attainment of national and international best practice.
Development and Preliminary Validation of the EASE: A Tool to Measure Perceived Singing Voice Function
Publisher: Elsevier BV
Date: 07-2013
DOI: 10.1016/J.JVOICE.2013.01.019
Abstract: Most voice self-rating tools are disease-specific measures and are not suitable for use with healthy voice users. There is a need for a tool that is sensitive to the subtleties of a singer's voice and to perceived physical changes in the singing voice mechanism as a function of load. The aim of this study was to devise and validate a scale to assess singer's perceptions of the current status of their singing voice. Ninety-five vocal health descriptors were collected from focus group interviews of singers. These were reviewed by 25 currently performing music theater (MT) singers. Based on a consensus technique, the number of descriptors was decreased to 42 items. These were administered to a s le of 284 professional MT singers using an online survey to evaluate their perception of current singing voice status. Principal component analysis identified two subsets of items. Rasch analysis was used to evaluate and refine these sets of items to form two 10-item subscales. Both subscales demonstrated good overall fit to the Rasch model, no differential item functioning by sex or age, and good internal consistency reliability. The two subscales were strongly correlated and subsequent Rasch analysis supported their combination to form a single 20-item scale with good psychometric properties. The Evaluation of the Ability to Sing Easily (EASE) is a concise clinical tool to assess singer's perceptions of the current status of their singing voice with good measurement properties. EASE may prove a useful tool to measure changes in the singing voice as indicators of the effect of vocal load. Furthermore, it may offer a valuable means for the prediction or screening of singers "at risk" of developing voice disorders.
Does Preoperative Atrial Fibrillation Portend a Poorer Prognosis in Patients Undergoing Isolated Aortic Valve Replacement? A Multicentre Australian Study
Publisher: Elsevier BV
Date: 06-2013
DOI: 10.1016/J.CJCA.2012.08.016
Abstract: Preoperative atrial fibrillation (preop-AF) has been associated with poorer early and late outcomes after cardiac surgery. Few studies, however, have evaluated the impact of preop-AF on early and late outcomes after isolated aortic valve replacement (AVR). Data obtained prospectively between June 2001 and December 2009 by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program was retrospectively analyzed. Patients who underwent concomitant atrial arrhythmia surgery/ablation were excluded. Demographic and operative data were compared between patients undergoing isolated AVR who presented with preop-AF and those in sinus rhythm. The independent effect of preop-AF on 12 short-term complications and long-term survival was determined using binary logistic and cox regression, respectively. Isolated AVR surgery was performed in 2789 patients 380 (13.6%) presented with preop-AF. Preop-AF patients were generally older (mean age, 73 vs 68 years P < 0.001) and presented more often with comorbidities including congestive heart failure, diabetes, and cerebrovascular disease (all P 0.05). Preop-AF was independently associated with reduced long-term survival (hazard ratio, 1.36 95% confidence interval, 1.01-1.83 P = 0.041). Preop-AF is associated with an increased risk of late mortality after isolated AVR. As such, concomitant atrial ablation with AVR should be prospectively studied.
Sliding Mode Control of a Piezoelectric Actuator with Neural Network Compensating Rate-Dependent Hysteresis
Publisher: IEEE
Date: 2005
Clinical characteristics and early mortality of patients undergoing coronary artery bypass grafting compared to percutaneous coronary intervention: Insights from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) and the Melbourne Interventional Group (MIG) Registries
Publisher: Elsevier BV
Date: 06-2009
DOI: 10.1016/J.HLC.2008.10.005
Abstract: Controversy continues over the optimal revascularisation strategy for patients with multi-vessel coronary artery disease. Clinical characteristics, risk profile, and mortality of patients undergoing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) are thought to differ but there are limited contemporary comparative data. We compared clinical characteristics, in-hospital and 30-day mortality of 3841 consecutive patients undergoing isolated CABG and 4417 undergoing PCI. Independent predictors of 30-day mortality were determined by multiple logistic regression analysis. CABG patients were older (p<0.01). The CABG group had a higher incidence of diabetes, heart failure, left ventricular ejection fraction <45%, multi-vessel coronary artery, peripheral vascular and cerebro-vascular disease (all p<0.01). Patients undergoing PCI had a higher incidence of recent myocardial infarction (MI) as the indication for revascularisation (p<0.01). In-hospital and 30-day mortality was 1.8% and 1.7% in the CABG group, and 1.4% and 1.8% in the PCI group, respectively. Independent predictors of 30-day mortality after CABG were age (odds ratio 1.1 per year, 95% confidence interval 1.0-1.1), cardiogenic shock (4.10, 1.7-10.5) and previous CABG (6.6, 2.4-17.7). Predictors after PCI were diabetes (2.7, 1.4-5.1), female gender (3.0, 1.6-5.5), renal failure (3.2, 1.2-8.0), MI<24h (4.0, 2.2-7.6), left main intervention (5.4, 1.0-27.7), heart failure (6.0, 2.6-14.0) and cardiogenic shock (11.7, 5.4-25.2). In contemporary clinical practice, CABG is preferred in patients with multi-vessel coronary and associated non-coronary vascular disease, while PCI is the dominant strategy for acute MI. Despite this, in-hospital and 30-day mortality rates were similar. Predictors of early mortality after CABG differ to those of PCI.
Quality Control Activities Associated with Registries in Interventional Cardiology and Surgery
Publisher: Elsevier BV
Date: 03-2011
DOI: 10.1016/J.HLC.2010.11.001
Abstract: To describe and outline audit and quality control activities of the multicentre interventional and cardiac surgery registry in Victoria as a potential model for a national registry. The Melbourne Interventional Group (MIG) database is a prospective multicentre registry recording consecutive percutaneous coronary interventional (PCI) procedures across eight Victorian hospitals. Similarly, the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) database captures cardiac surgical activity across six Victorian hospitals. Auditing of each registry involved systematic selection of baseline, clinical and procedural variables from 5% of procedures to examine for data integrity and mismatches. Performance trend and data accuracy of each registry was assessed by the number of mismatches detected during the auditing process for different demographic, clinical and procedural variables and across different (de-identified) sites. Over two auditing phases from 2004-2006 and 2007, 10 (4.3%) of variables from 3% of all PCI procedures and 15 (6.4%) variables from 5% of PCI procedures were analysed. There was 96.5% agreement during the first auditing phase of the MIG registry with an average of 0.35 mismatches per audit (CI 0.28-0.42), whereas during the second audit phase, agreement was up to 97% with 0.32 mismatches per 10 fields per audit (CI 0.25-0.40). The ASCTS database audit selected 39 (14.8%) variables from 5% of annual surgical cases across six cardiac surgical centres with an overall 96.7% agreement. The current auditing process of these two databases is rigorous, robust and reflects a high degree of accuracy of data collected by participating hospitals.
Minimally Invasive Right Heart Operations: Techniques for Bicaval Occlusion and Cardioplegia
Publisher: Elsevier BV
Date: 12-1997
DOI: 10.1016/S0003-4975(97)01006-0
Abstract: Peripheral cardiopulmonary bypass with cardioplegia has facilitated minimally invasive coronary artery bypass grafting and mitral valve replacement. The cardiopulmonary bypass system was modified to allow bicaval occlusion for right heart operations. In 4 canine studies, three variants of bicaval cannulation techniques were successfully used for atrial septal defect repair via a right minithoracotomy.
Validation of the EuroSCORE model in Australia
Publisher: Oxford University Press (OUP)
Date: 04-2006
DOI: 10.1016/J.EJCTS.2005.12.046
Abstract: There is an important role for accurate risk prediction models in current cardiac surgical practice. Such models enable benchmarking and allow surgeons and institutions to compare outcomes in a meaningful way. They can also be useful in the areas of surgical decision-making, preoperative informed consent, quality assurance and healthcare management. The aim of this study was to assess the performance of the European System for Cardiac Operative Risk Evaluation (EuroSCORE) model on the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) patient database. The additive and logistic EuroSCORE models were applied to all patients undergoing cardiac surgery at six institutions in the state of Victoria between 1st July 2001 and 4th July 2005 within the ASCTS database who have complete data. The entire cohort and a subgroup of patients undergoing coronary artery bypass grafting (CABG) only were analysed. Observed and predicted mortalities were compared. Model discrimination was tested by determining the area under the receiver operating characteristic (ROC) curve. Model calibration was tested by the Hosmer-Lemeshow chi-square test. Eight thousand three hundred and thirty-one patients with complete data were analysed. There were significant differences in the prevalence of risk factors between the ASCTS and European cardiac surgical populations. Observed mortality was 3.20% overall and 2.00% for the CABG only group. The EuroSCORE models over estimated mortality (entire cohort: additive predicted 5.31%, logistic predicted 8.76% CABG only: additive predicted 4.25%, logistic predicted 6.19%). Discriminative power of both models was very good. Area under ROC curve was 0.83 overall and 0.82 for the CABG only group. Calibration of both models was poor as mortality was over predicted at nearly all risk deciles. Hosmer-Lemeshow chi-square test returned P-values less than 0.05. The additive and logistic EuroSCORE does not accurately predict outcomes in this group of cardiac surgery patients from six Australian institutions. Hence, the use of the EuroSCORE models for risk prediction may not be appropriate in Australia. A model, which accurately predicts outcomes in Australian cardiac surgical patients, is required.
Simulation of deformable models with the Poisson equation
Publisher: Informa UK Limited
Date: 10-2006
DOI: 10.1080/10255840600908503
Abstract: In this paper, we present a new methodology for the deformation of soft objects by drawing an analogy between the Poisson equation and elastic deformation from the viewpoint of energy propagation. The potential energy stored due to a deformation caused by an external force is calculated and treated as the source injected into the Poisson system, as described by the law of conservation of energy. An improved Poisson model is developed for propagating the energy generated by the external force in a natural manner. An autonomous cellular neural network (CNN) model is established by using the analogy between the Poisson equation and CNN to solve the Poisson model for the real-time requirement of soft object deformation. A method is presented to derive the internal forces from the potential energy distribution. The proposed methodology models non-linear materials with the non-linear Poisson equation and thus non-linear CNN, rather than geometric non-linearity. It not only deals with large-range deformations, but also accommodates isotropic, anisotropic and inhomogeneous materials by simply modifying constitutive coefficients. A haptic virtual reality system has been developed for deformation simulation with force feedback. Ex les are presented to demonstrate the efficiency of the proposed methodology.
Recovery of Cognitive Function After Coronary Artery Bypass Graft Operations
Publisher: Elsevier BV
Date: 04-2013
DOI: 10.1016/J.ATHORACSUR.2012.11.021
Abstract: The effect of coronary artery bypass grafting (CABG) operations on cognition was examined after controlling for the operation, emotional state, preexisting cognitive impairment, and repeated experience with cognitive tests. On-pump CABG patients (n=16), thoracic surgical patients (n=15), and a nonsurgical control group (n=15) were tested preoperatively, and at 1 and 8 weeks postoperatively, using a battery of cognitive tests and an emotional state assessment. Patient groups were similar in age, sex, level of education, and premorbid intelligence quotient score. Surgical group data were normalized against data from the nonsurgical control group before statistical analysis. CABG patients performed worse on every subtest before the operation, and this disadvantage persisted after the operation. Anxiety, depression, and stress were associated with impaired cognitive performance in the surgical groups 1 week after the operation: 44% of CABG patients and 33% of surgical control patients were significantly impaired yet, by 8 weeks, nearly all patients had recovered to preoperative levels, with 25% of CABG and 13% of surgical control patients improving beyond their preoperative performance. Stress, anxiety, and depression impair cognitive performance in association with CABG and thoracic operations. Most patients recover to, or exceed, preoperative levels of cognition within 8 weeks. Thus, after controlling for nonsurgical factors, the prospects of a tangible improvement in cognition after CABG are high.
Sex differences in outcomes following isolated coronary artery bypass graft surgery in Australian patients: Analysis of the Australasian Society of Cardiac and Thoracic Surgeons cardiac surgery database
Publisher: Oxford University Press (OUP)
Date: 13-12-2012
DOI: 10.1093/EJCTS/EZR013
Hospital mortality under surgical care
Publisher: Royal College of Surgeons of England
Date: 03-2012
Development of a short form of the Cardiac Distress Inventory
Publisher: Research Square Platform LLC
Date: 07-07-2023
DOI: 10.21203/RS.3.RS-3143853/V1
Abstract: Background Cardiac distress may be viewed as a persistent negative emotional state that spans multiple psychosocial domains and challenges a patient’s capacity to cope with living with their heart condition. The Cardiac Distress Inventory (CDI) is a disease-specific clinical assessment tool that captures the complexity of this distress. In busy settings such as primary care, cardiac rehabilitation, and counselling services, however, there is a need to administer briefer tools to aid in identification and screening. The aim of the present study was to develop a short, valid screening version of the CDI. Methods A total of 405 participants reporting an acute coronary event in the previous 12 months was recruited from three hospitals, through social media and by direct enrolment on the study website. Participants completed an online survey which included the full version of the CDI and general distress measures including the Kessler K6, Patient Health Questionnaire-4, and Emotion Thermometers. Relationship of the CDI with these instruments, Rasch analysis model fit and clinical expertise were all used to select items for the short form (CDI-SF). Construct validity and receiver operating characteristics in relation to the Kessler K6 were examined. Results The final 12 item CDI-SF exhibited excellent internal consistency indicative of unidimensionality and good convergent and discriminant validity in comparison to clinical status measures, all indicative of good construct validity. Using the K6 validated cutoff of ≥18 as the reference variable, the CDI-SF had a very high Area Under the Curve (AUC) (AUC = 0.913 (95% CI: 0.88 to 0.94). A CDI-SF score of ≥ 13 was found to indicate general cardiac distress which may warrant further investigation using the original CDI. Conclusion The psychometric findings detailed here indicate that CDI-SF provides a brief psychometrically sound screening measure indicative of general cardiac distress, that can be used in both clinical and research settings.
Sliding-mode enhanced adaptive motion tracking control of piezoelectric actuation systems for micro/nano manipulation
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2008
Combined Cardiac and Lung Volume Reduction Surgery
Publisher: Elsevier BV
Date: 05-2009
DOI: 10.1016/J.THORSURG.2009.04.001
Abstract: Coronary artery disease is prevalent in patients who have severe emphysema and who are being considered for lung volume reduction surgery (LVRS). Significant valvular heart diseases may also coexist in these patients. Few thoracic surgeons have performed LVRS in patients who have severe cardiac diseases. Conversely, few cardiac surgeons have been willing to undertake major cardiac surgery in patients who have severe emphysema. This report reviews the evidence regarding combined cardiac surgery and LVRS to determine the optimal management strategy for patients who have severe emphysema and who are suitable for LVRS, but who also have coexisting significant cardiac diseases that are operable.
Impact of renal function in patients with multi-vessel coronary disease on long-term mortality following coronary artery bypass grafting compared with percutaneous coronary intervention
Publisher: Elsevier BV
Date: 03-2014
DOI: 10.1016/J.IJCARD.2014.01.096
Abstract: Comorbidities, such as diabetes, affect revascularization strategy for coronary disease. We sought to determine if the degree of renal impairment affected long-term mortality after percutaneous coronary intervention (PCI) compared to coronary artery bypass grafting (CABG) in patients with multi-vessel coronary disease (MVD). 8970 patients with MVD undergoing revascularization between 2004 and 2008, in two multi-center parallel PCI and CABG Australian registries were assigned to three groups based on their estimated glomerular filtration rate (eGFR)≥60 mL/min/1.73 m2 (n=1678:839), 30-59 mL/min/1.73 m2 (n=452:226) and <30 mL/min/1.73 m2 (n=74:37). We used 2:1 propensity matching to compare 3306 patients undergoing primary CABG versus PCI. Shock, myocardial infarction (MI)<24 h, previous CABG, valve surgery or PCI were exclusions. Long-term mortality (mean 3.1 years) was compared with Cox-proportional hazard-adjusted modeling. Observed long-term mortality rates (CABG vs. PCI) were 4.5% vs. 4.3% p=0.84, 12.8% vs. 17.3% p=0.12, and 23.0% vs. 40.5% p=0.05 in the three strata, respectively. In patients with eGFR≥60 mL/min/1.73 m2, long-term mortality between PCI and CABG (HR 0.99, 95% CI 0.65-1.49, p=0.95) was similar. However, amongst patients with eGFR 30-59 mL/min/1.73 m2, there was a significant mortality hazard with PCI (HR 2.00, 95% CI 1.32-3.04, p=0.001). In patients with eGFR<30 mL/min/1.73 m2, there was a trend for hazard with PCI (HR 1.66, 95% CI 0.80-3.46, p=0.17). Long-term mortality in MVD patients with preserved renal function was very low and similar between PCI and CABG. However there was a long-term mortality hazard associated with PCI amongst patients with moderate renal impairment.
Empyema thoracis: 14-year experience in a teaching center
Publisher: Elsevier BV
Date: 1991
DOI: 10.1016/0003-4975(91)90443-T
Abstract: One hundred two patients with empyema thoracis were managed at the Royal Melbourne Hospital between 1976 and 1989. Fifty-five cases of empyema thoracis were postpneumonic, 8 followed esophageal rupture, and 5 were associated with thoracic trauma. Some form of systemic illness was a major contributing factor in the presentation of 29 patients. A single causal organism was found in 53 patients (the most common being Staphylococcus aureus), multiple organisms in 36, and no growth in 13. During the years 1983 to 1989 there was an increased incidence of empyemas caused by multiple or antibiotic-resistant organisms. Operative drainage was required in 90 patients and 12 were managed by thoracentesis or intercostal tube drainage alone. The in-hospital mortality rate for patients managed nonoperatively was 58% (7 of 12 patients) it was 16% (14 of 90 patients) for those receiving operative drainage. There were seven late deaths, four empyema related and three nonrelated. Early adequate operative drainage is recommended for patients with empyema thoracis.
Postoperative atrial fibrillation after isolated aortic valve replacement: A cause for concern?
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.ATHORACSUR.2012.08.077
Abstract: Several studies have shown that postoperative atrial fibrillation (POAF) is associated with poorer short-term and long-term outcomes after general cardiac operations. There is, however, a paucity of data on the impact of POAF on outcomes after isolated aortic valve replacement (AVR). Data for all patients undergoing isolated first-time AVR between June 2001 and December 2009 was obtained from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) National Cardiac Surgery Database Program and a retrospective analysis was conducted. Preoperative characteristics, early postoperative outcome, and late survival were compared between patients in whom POAF developed and those in whom it did not. Propensity score matching was performed to correct for differences between the 2 groups. Excluding patients with preoperative arrhythmia, isolated first-time AVR was performed in 2,065 patients. POAF developed in 725 (35.1%) of them. Patients with POAF were significantly older (mean age, 72 versus 65 years p < 0.001) and presented more often with comorbidities, including hypertension, respiratory disease, and hypercholesterolemia (all p < 0.05). From the initial study population, 592 propensity-matched patient pairs were derived the overall matching rate was 81.7%. In the matched groups, 30-day mortality was not significantly different between the POAF and non-POAF groups (1.5% versus 1% p = 0.48). Patients with POAF were, however, at an independently increased risk of perioperative complications, including new renal failure, gastrointestinal complications, and 30-day readmission (p < 0.05). Seven-year mortality was not significantly different between POAF and non-POAF groups (78% versus 83% p = 0.63). POAF is a risk factor for short-term morbidity but is not associated with a higher rate of early or late mortality after isolated AVR.
Procedure-specific Cardiac Surgeon Volume associated with Patient outcome following Valve Surgery, but not Isolated CABG Surgery
Publisher: Elsevier BV
Date: 06-2015
DOI: 10.1016/J.HLC.2014.11.014
Abstract: Trends towards surgical sub-specialisation to improve patient-outcomes are well-documented and largely supported by evidence. However few studies have examined whether this benefit exists within adult-cardiac surgery. To answer whether sub-specialisation within adult-cardiac surgery improves patient-outcomes, this study assessed the relationship between procedure-specific and total-cardiac surgeon-volume and mortality and morbidity in cardiac-valve and coronary artery bypass grafting (CABG) surgery. Data came from the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) registry from 2001 to 2010 and included 23 hospitals, 109 surgeons, 20,619 patients with isolated-CABG-surgery and 11,536 patients with a valve-procedure. Hierarchical logistic regression using generalised estimating equations was used to analyse outcomes. Measures included operative-mortality and occurrence of a complication (deep sternal wound infection, new stroke, acute kidney injury). Crude operative mortality (and complication rates) were 1.7% (4.9%) and 4% (11%) in the isolated-CABG and valve-surgical populations respectively. A greater procedure-specific surgeon volume was associated with reduced mortality and complication rates in valve-surgery but not isolated-CABG. There was a 33% decrease in odds of dying for every additional 50 valve procedures performed [OR 0.67, p=0.003]. Conversely, greater total-cardiac surgical volume for in idual surgeons did not result in improved outcomes, for both isolated-CABG and valve populations. Our finding of an association between increased valve-specific surgeon volumes with improved valve-surgery outcomes, and absence of an association between these outcomes and annual total-cardiac surgical experience supports the case for sub-specialisation specifically within the field of valve surgery.
Introduction of universal prestorage leukodepletion of blood components, and outcomes in transfused cardiac surgery patients
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1016/J.JTCVS.2015.03.015
Abstract: To assess whether introduction of universal leukodepletion (ULD) of red blood cells (RBCs) for transfusion was associated with improvements in cardiac surgery patient outcomes. Retrospective study (2005-2010) conducted at 6 institutions. Associations between leukodepletion and outcomes of mortality, infection, and acute kidney injury (AKI) were modeled by logistic regression, and intensive care unit length of stay (LOS) in survivors was explored using linear regression. To examine trends over time, odds ratios (ORs) for outcomes of transfused were compared with nontransfused patients, including a comparison with nontransfused patients who were selected based on propensity score for RBC transfusion. We studied 14,980 patients, of whom 8857 (59%) had surgery pre-ULD. Transfusions of RBCs were made in 3799 (43%) pre-ULD, and 2525 (41%) post-ULD. Administration of exclusively leukodepleted, versus exclusively nonleukodepleted, RBCs was associated with lower incidence of AKI (adjusted OR 0.80, 95% confidence interval [CI] 0.65-0.98, P = .035), but no difference in mortality or infection. For post-ULD patients, no difference was found in mortality (OR 0.96, 95% CI 0.76-1.22, P = .76) or infection (OR 0.91, 95% CI 0.79-1.03, P = .161) however, AKI was reduced (OR 0.79 95% CI 0.68-0.92, P = .003). However, ORs for post-ULD outcomes were not significantly different in nontransfused, versus transfused, patients. Furthermore, those who received exclusively nonleukodepleted RBCs were more likely to have surgery post-ULD. Universal leukodepletion was not associated with reduced mortality or infection in transfused cardiac surgery patients. An association was found between ULD and reduced AKI however, this reduction was not significantly different from that seen in nontransfused patients, and other changes in care most likely explain such changes in renal outcomes.
Credentialing of surgeons: A systematic review across a number of jurisdictions
Publisher: Wiley
Date: 07-2012
DOI: 10.1111/J.1445-2197.2012.06115.X
Abstract: Background: The purpose of credentialing is to ensure that clinicians provide safe, high‐quality health‐care services in accordance with good practice and legal requirements. This review assessed the institutional credentialing processes and governance structures required to support credentialing processes at an institutional, regional or health‐care system level. Methods: Searches of MEDLINE, EMBASE and PubMed were conducted. Additional grey literature searches were performed using the Google search engine and specific searches of government web sites were conducted. The inclusion criteria were developed a priori and standardized extraction of the information to appraise the research questions was conducted systematically. Results: A total of 33 white papers were included in this systematic literature review: 18 were published in Australia, 1 in New Zealand, 10 in the United Kingdom, 2 in the United States of America and 2 in Canada. Four key principles were common throughout all studies included in this review: clear lines of responsibility for the credentialing process and supportive governance structures, clear standards for credentialing, a culture of continuous improvement and evaluation of credentialing process outcomes. Conclusions: No data were available to evaluate the relationship between the credentialing process and the safety and quality of health‐care services or patient outcomes and capturing such data is difficult because of the numerous factors that affect the relationship between credentialing, patient outcomes, and the safety and quality of health‐care services. Consequently, developing methods to measure the effectiveness of credentialing processes represents an area for further research.
Developing performance indicators for cardiac surgery: A demonstration project in Victoria
Publisher: Elsevier BV
Date: 2001
DOI: 10.1046/J.1444-2892.2001.00073.X
Abstract: Six Victorian cardiac surgical units pooled data in order to undertake a demonstration project aimed at developing performance indicators to assess outcomes following cardiac surgery. The outcome of the project was an indicative report for the purpose of monitoring surgical performance indicators in a format suitable for: (i) the general public (ii) the Victorian State Government and (iii) the participating units and surgeons. Each participating cardiac surgical unit had an existing database used for recording information from each procedure. A request was made to each unit to extract a subset of data from all cases entered over the past 5 years. The proposed list of performance indicators included surgical mortality (within the period of admission for surgery), complication rates (including sternal infection, postoperative myocardial infarction, postoperative stroke, haemorrhage requiring return to theatre), and length of hospital stay. A model was developed from the data and used to provide risk-adjusted measures of hospital performance. Cases from five cardiac surgical units (n = 10 715) were included in the final analysis. A risk-adjusted model (including age, sex, diabetes, hypertension, smoking, procedure type, urgency of procedure) was developed for surgical mortality. Performance indicators for coronary artery bypass graft surgery, including mortality, sternal infection rate and length of hospital stay are presented. From the available data, performance indicators for cardiac surgery in Victorian hospitals compared favourably with international benchmarks. This project has demonstrated that prospective data collection using a standardised system could readily produce local risk-adjustment models for cardiac surgery to aid in developing appropriate performance indicators.
Impact of prosthesis - Patient mismatch after mitral valve replacement: A multicentre analysis of early outcomes and mid-term survival
Publisher: BMJ
Date: 20-05-2011
Abstract: Prosthesis-patient mismatch (PPM) is characterised by the effects of inadequate prosthesis size relative to body surface area (BSA). It is uncertain whether PPM after mitral valve replacement impacts upon clinical outcome. This was examined in an Australian population. From 2001 to 2009, 1006 mechanical and bioprosthetic mitral valves were implanted across 10 institutions. Effective orifice areas (EOA) were obtained from a literature review of in vivo echocardiographic data. Absent, moderate and severe PPM was defined as an indexed EOA (EOA/BSA) of >1.20 cm(2)/m(2), >0.90 to ≤1.20 cm(2)/m(2) and ≤0.9 cm(2)/m(2), respectively. Early outcomes and 7-year survival were compared between these three groups. PPM was absent in 34%, moderate in 53% and severe in 13% of patients. Patients with PPM were more likely to be male (42% vs 52% vs 62%, p<0.0001) and obese (14% vs 20% vs 56%, p<0.0001). Postoperatively there was similar 30-day mortality (5% vs 5% vs 6%, p=0.83) and early any mortality/morbidity (24% vs 27% vs 29%, p=0.40). Seven-year survival was similar between groups (72±4.1% vs 76±3.2% vs 69±10.3%, p=0.76). PPM did not predict adverse events after logistic and Cox regressions with and without propensity score adjustment. Subgroup analyses of those with isolated mitral valve surgery, patients with preoperative congestive heart failure and non-obese patients failed to show an association between PPM and mid-term mortality. Overall, PPM was not associated with poorer early outcomes or mid-term survival. Oversizing valves may be technically hazardous and do not yield superior outcomes. Easier implantation by appropriate sizing appears justified.
The potential for bronchoscopic lung volume reduction using bronchial prostheses: A pilot study
Publisher: Elsevier BV
Date: 09-2003
Abstract: Significant morbidity and mortality offset the benefits of lung volume reduction surgery (LVRS) for emphysema. By contributing to distal lung collapse, bronchoscopic placement of valved prostheses has the potential to noninvasively replicate the beneficial effects of LVRS. The purpose of this study was to investigate the safety and feasibility of placing valves in segmental airways of patients with emphysema. Case series. Tertiary hospital, severe airways disease clinic. Ten patients aged 51 to 69 years with apical emphysema and hyperinflation, otherwise suitable for standard LVRS. Mean preoperative FEV(1) was 0.72 L (19 to 46% predicted), and 6-min walk distance was 340 m (range, 245 to 425 m). Apical, bronchoscopic, segmental airway placement of one-way valves (silicone-based Nitinol bronchial stent Emphasys Medical Redwood City, CA) under general anesthesia. Placement was over a guidewire under bronchoscopic and fluoroscopic control. Four to 11 prostheses per patient took 52 to 137 min to obstruct upper-lobe segments bilaterally. Inpatient stay was 1 to 8 days. No major complications were seen in the 30-day study period. Minor complications included exacerbation of COPD (n = 3), asymptomatic localized pneumothorax (n = 1), and lower-lobe pneumonia (day 37 n = 1). Symptomatic improvement was noted in four patients. No major change in radiologic findings, lung function, or 6-min walk distance was evident at 1 month, although gas transfer improved from 7.47 +/- 2.0 to 8.26 +/- 2.6 mL/min/mm Hg (p = 0.04) and nuclear upper-lobe perfusion fell from 32 +/- 10 to 27 +/- 9% (mean +/- SD) [p = 0.02]. Bronchoscopic prostheses can be safely and reliably placed into the human lung. Further study is needed to explore patient characteristics that determine symptomatic efficacy in a larger patient cohort.
Does Prior Percutaneous Coronary Intervention Adversely Affect Early and Mid-Term Survival After Coronary Artery Surgery?
Publisher: Elsevier BV
Date: 08-2009
DOI: 10.1016/J.JCIN.2009.04.018
Abstract: To determine the association between previous percutaneous coronary intervention (PCI) and results after coronary artery bypass graft surgery (CABG). Increasing numbers of patients undergoing CABG have previously undergone PCI. We analyzed consecutive first-time isolated CABG procedures within the Australasian Society of Cardiac and Thoracic Surgeons Database from June 2001 to May 2008. Logistic regression and propensity score analyses were used to assess the risk-adjusted impact of prior PCI on in-hospital mortality and major adverse cardiac events. Cox regression model was used to assess the effect of prior PCI on mid-term survival. Of 13,184 patients who underwent CABG, 11,727 had no prior PCI and 1,457 had prior PCI. Mean follow-up was 3.3 +/- 2.1 years. Patients without prior PCI had a higher EuroSCORE value (4.4 +/- 3.3 vs. 3.6 +/- 3.0, p < 0.001), were older, and more likely to have left main stem stenosis and recent myocardial infarction. There was no difference in unadjusted in-hospital mortality (1.65% vs. 1.55%, p = 0.78) or major adverse cardiac events (3.0% vs. 3.0%, p = 0.99) between patients with or without prior PCI. After adjustment, prior PCI was not a predictor of in-hospital (odds ratio: 1.22, 95% confidence interval [CI]: 0.76 to 2.0, p = 0.41) or mid-term mortality at 6-year follow-up (hazard ratio: 0.94, 95% CI: 0.75 to 1.18, p = 0.62). In this large registry study, prior PCI was not associated with increased short- or mid-term mortality after CABG. Good outcomes can be obtained in the group of patients undergoing CABG who have had previous PCI.
Risk factors for surgical wound infection and bacteraemia following coronary artery bypass surgery
Publisher: Wiley
Date: 2000
DOI: 10.1046/J.1440-1622.2000.01742.X
Abstract: There has been no consensus from previous studies of risk factors for surgical wound infections (SWI) and postoperative bacteraemia for patients undergoing coronary artery bypass graft (CABG) surgery. Data on 15 potential risk factors were prospectively collected on all patients undergoing CABG surgery during a 12-month period. Of 693 patients, 62 developed 65 SWI using the Centres for Disease Control definition: 23 were sternal wound infections and 42 were arm or leg wound infections at the site of conduit harvest. There were 19 episodes of postoperative bacteraemia. Multivariate analysis revealed that: (i) diabetes, obesity and previous cardiovascular procedure were independent predictors of SWI and (ii) obesity was an independent risk factor for postoperative bacteraemia. These findings suggest that improved diabetic control and pre-operative weight reduction may result in a decrease in the incidence of SWI. But further prospective studies need to be undertaken to examine (i) whether the increased SWI risk in diabetes occurs with both insulin- and non-insulin-requiring diabetes, and whether improved peri-operative diabetes control decreases SWI and (ii) what degree of obesity confers a risk of SWI and postoperative bacteraemia, and whether pre-operative weight reduction, if a realistic strategy in this patient group, results in a decrease in SWI.
Urgent and emergency coronary artery bypass grafting for acute coronary syndromes
Publisher: Wiley
Date: 16-08-2006
DOI: 10.1111/J.1445-2197.2006.03864.X
Abstract: Urgent and emergency coronary artery bypass grafting may be associated with significant mortality and morbidity. We report our recent experience with this group of patients. A retrospective analysis of 441 patients undergoing urgent and emergency surgery over a 3-year period was carried out. Multivariate analysis was used to identify subgroups of patients who were most at risk of death. The 30-day mortality was 3.3 and 16.3% in the urgent and emergency groups, respectively. Urgent surgery was associated with significantly shorter duration of ventilation (16 h vs 69 h) and stay at the intensive care unit (31 h vs 102 h). The incidence of pneumonia, pulmonary embolism, renal failure and neurological events were also less in the urgent group. The preoperative use of the intra-aortic balloon pump was low (0.8% in the urgent group and 4.8% in the emergency group). Multivariate analysis showed that patients over 70 years of age (odds ratio 3.2, 95% confidence interval 1.1-9.5) with left main stenosis (odds ratio 4.4, 95% confidence interval 1.5-12.4) complicated by cardiogenic shock (odds ratio 17.8, 95% confidence interval 5.2-61.1) were at highest risk of death. Patients transferred directly to theatre from cardiac catheter laboratory following failed percutaneous interventions were found to be most at risk. Mortality in this group was 29%, with 50% patients being in shock and 36% having left main stenosis. Satisfactory results have been obtained in urgent coronary artery bypass grafting, but acute coronary syndromes complicated by cardiogenic shock remain a high-risk group. Further studies are needed to define the optimal operative management in this group of patients.
Extra-Aortic Implantable Counterpulsation Pump in Chronic Heart Failure
Publisher: Elsevier BV
Date: 06-2008
DOI: 10.1016/J.ATHORACSUR.2007.12.049
Abstract: Extra-aortic counterpulsation for the management of chronic heart failure is a novel approach. We report the use of an extra-aortic implantable counterpulsation pump in the management of a 73-year-old patient with severe heart failure refractory to medical therapy. The implantable counterpulsation pump prolonged his life and greatly improved its quality. The patient lived almost 7 months after the implantation of the device and died of septic complications secondary to gas line infection.
Enhanced sliding mode motion tracking control of piezoelectric actuators
Publisher: Elsevier BV
Date: 07-2007
Dynamic Four-dimensional Computed Tomography (4D CT) Imaging for Re-entry Risk Assessment in Re-do Sternotomy - First experience
Publisher: Elsevier BV
Date: 10-2015
DOI: 10.1016/J.HLC.2015.02.027
Abstract: Repeat cardiac surgeries are well known to have higher rates of complications, one of the important reasons being injuries associated with re-do sternotomy. Routine imaging with CT can help to minimise this risk by pre-operatively assessing the anatomical relation between the sternum and the underlying cardiovascular structures, but is limited by its inability to determine the presence and severity of functional tethering and adhesions between these structures. However, with the evolution of wide area detector MD CT scanners, it is possible to assess the presence of tethering using the dynamic four-dimensional CT (4D CT) imaging technique. Nineteen patients undergoing re-do cardiac surgery were pre-operatively imaged using dynamic 4D CT during regulated respiration. The datasets were assessed in cine mode for presence of differential motion between sternum and underlying cardiovascular structures which indicates lack of significant tethering. Overall, there was excellent correlation between preoperative imaging and intraoperative findings. The technique enabled our surgeons to meticulously plan the procedures and to avoid re-entry related injuries. Our initial experience shows that dynamic 4D CT is useful in risk stratification prior to re-do sternotomy by determining the presence or absence of tethering between sternum and underlying structures based on assessment of differential motion. Furthermore we determined the technique to be superior to non-dynamic assessment of retrocardiac tethering.
A Force-Feedback Methodology for Teleoperated Suturing Task in Robotic-Assisted Minimally Invasive Surgery
Publisher: MDPI AG
Date: 14-10-2022
DOI: 10.3390/S22207829
Abstract: With robotic-assisted minimally invasive surgery (RAMIS), patients and surgeons benefit from a reduced incision size and dexterous instruments. However, current robotic surgery platforms lack haptic feedback, which is an essential element of safe operation. Moreover, teleportation control challenges make complex surgical tasks like suturing more time-consuming than those that use manual tools. This paper presents a new force-sensing instrument that semi-automates the suturing task and facilitates teleoperated robotic manipulation. In order to generate the ideal needle insertion trajectory and pass the needle through its curvature, the end-effector mechanism has a rotating degree of freedom. Impedance control was used to provide sensory information about needle–tissue interaction forces to the operator using an indirect force estimation approach based on data-based models. The operator’s motion commands were then regulated using a hyperplanar virtual fixture (VF) designed to maintain the desired distance between the end-effector and tissue surface while avoiding unwanted contact. To construct the geometry of the VF, an optoelectronic sensor-based approach was developed. Based on the experimental investigation of the hyperplane VF methodology, improved needle–tissue interaction force, manipulation accuracy, and task completion times were demonstrated. Finally, experimental validation of the trained force estimation models and the perceived interaction forces by the user was conducted using online data, demonstrating the potential of the developed approach in improving task performance.
Right atrial perforation by a temporary epicardial pacing wire
Publisher: Elsevier BV
Date: 07-1990
DOI: 10.1016/0003-4975(90)90110-R
Abstract: Cardiac perforation by an epicardial pacing wire is an extremely rare event. A case of right atrial perforation occurring 10 hours after coronary artery bypass grafting is reported. Another cause of bleeding and cardiac t onade after cardiac operation is therefore illustrated.
Lung Volume Reduction Surgery in Australia and New Zealand. Six Years On: Registry Report
Publisher: Elsevier BV
Date: 10-2003
Abstract: Lung volume reduction surgery (LVRS) has been shown to improve lung function, exercise performance, and quality of life in highly selected in iduals with severe emphysema however, major questions regarding the efficacy and long-term outcomes of LVRS still remain unanswered. Pending the results of large randomized controlled trials (RCTs), the Australian and New Zealand LVRS Database was created to audit local clinical practice and patient outcomes. To review patient selection, surgical activity, and patient outcomes related to LVRS in Australia and New Zealand. Prospective data were voluntarily submitted by hospitals performing LVRS in Australia and New Zealand. Preoperative, surgical, perioperative, and follow-up variables were analyzed. Data were collected from 15 hospitals regarding 529 patients. Mean age (+/- SD) at surgery was 63 +/- 7 years. Preoperatively, FEV(1) was 29 +/- 9% predicted, total lung capacity (TLC) was 138 +/- 20% predicted, residual volume (RV) was 250 +/- 64% predicted, and 6-min walk (6MW) distance was 327 +/- 111 m. There has been a reduction in the overall number of cases and hospitals performing LVRS since 1999. Improvements in lung function following LVRS (ie, FEV(1) increase of 38%, RV decrease of 27%, TLC decrease of 17%) and exercise capacity (ie, 6MW distance increase of 24%) appear to be maintained for approximately 3 years. LVRS continues to be performed in Australia and New Zealand, predominantly in large tertiary teaching hospitals with similar outcomes to those described in the literature. It remains difficult to capture long-term lung function and survival outcomes in this population. Ongoing audit and RCTs are both required to resolve the confusion that still shrouds this procedure.
An Australian risk prediction model for 30-day mortality after isolated coronary artery bypass: The AusSCORE
Publisher: Elsevier BV
Date: 10-2009
DOI: 10.1016/J.JTCVS.2009.03.020
Abstract: Our objective was to identify risk factors associated with 30-day mortality after isolated coronary artery bypass grafting in the Australian context and to develop a preoperative model for 30-day mortality risk prediction. Preoperative risk associated with cardiac surgery can be ascertained through a variety of risk prediction models, none of which is specific to the Australian population. Recently, it was shown that the widely used EuroSCORE model validated poorly for an Australian cohort. Hence, a valid model is required to appropriately guide surgeons and patients in assessing preoperative risk. Data from the Australasian Society of Cardiac and Thoracic Surgeons database project was used. All patients undergoing isolated coronary artery bypass grafting between July 2001 and June 2005 were included for analysis. The data were ided into creation and validation sets. The data in the creation set was used to develop the model and then the model was validated in the validation set. Preoperative variables with a P value of less than .25 in chi(2) analysis were entered into multiple logistic regression analysis to develop a preoperative predictive model. Bootstrap and backward elimination methods were used to identify variables that are truly independent predictors of mortality, and 6 candidate models were identified. The Akaike Information Criteria (AIC) and prediction mean square error were used to select the final model (AusSCORE) from this group of candidate models. The AusSCORE model was then validated by average receiver operating characteristic, the P value for the Hosmer-Lemeshow goodness-of-fit test, and prediction mean square error obtained from n-fold validation. Over the 4-year period, 11,823 patients underwent cardiac surgery, of whom 65.9% (7709) had isolated coronary bypass procedures. The 30-day mortality rate for this group was 1.74% (134/7709). Factors selected as independent predictors in the preoperative isolated coronary bypass AusSCORE model were as follows: age, New York Heart Association class, ejection fraction estimate, urgency of procedure, previous cardiac surgery, hypercholesterolemia (lipid-lowering treatment), peripheral vascular disease, and cardiogenic shock. The average area under the receiver operating characteristic was 0.834, the P value for the Hosmer-Lemeshow chi(2) test statistic was 0.2415, and the prediction mean square error was 0.01869. We have developed a preoperative 30-day mortality risk prediction model for isolated coronary artery bypass grafting for the Australian cohort.
Early and late outcomes after isolated aortic valve replacement in octogenarians: An Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Study
Publisher: Oxford University Press (OUP)
Date: 05-2012
Intraoperative renal hypoxia and risk of cardiac surgery‐associated acute kidney injury
Publisher: Hindawi Limited
Date: 29-07-2021
DOI: 10.1111/JOCS.15859
Abstract: Acute kidney injury (AKI) is common after cardiac surgery requiring cardiopulmonary bypass. Renal hypoxia may precede clinically detectable AKI. We compared the efficacy of two indices of renal hypoxia, (i) intraoperative urinary oxygen tension (UPO In 82 patients undergoing on-pump cardiac surgery, blood s les were taken upon induction of anesthesia and upon entry into the intensive care unit. UPO Thirty-two (39%) patients developed postoperative AKI. pEPO increased during surgery, but this increase did not predict AKI, regardless of risk of postoperative mortality assessed by EuroSCORE-II. For patients categorized at higher risk by EuroSCORE-II >1.98 (median score for the cohort), UPO Intraoperative change in pEPO does not predict AKI. However, UPO
ANZSCTS Response to the Discussion Paper: Proposed Recommendations for Myocardial Revascularisation
Publisher: Elsevier BV
Date: 07-2015
Transesophageal Echocardiography Guidance of Antegrade Cardioplegia Delivery for Cardiac Surgery
Publisher: Elsevier BV
Date: 12-2016
DOI: 10.1053/J.JVCA.2015.03.009
Abstract: The initial volume of antegrade cardioplegia used to induce asystole during aortic cross-cl still is based on empiric methods and may be excessive, potentially leading to hyperkalemia, myocardial edema, and acute left ventricular distention from aortic regurgitation. The objectives were to determine whether the volume of cardioplegia required to induce asystole is proportional to left ventricular mass, and whether the degree of left ventricular distention is proportional to the severity of aortic regurgitation. Prospective observational study. Two tertiary university hospitals. Transesophageal echocardiography was used to estimate left ventricular mass (prolate ellipse revolution formula), quantify aortic regurgitation, and monitor for distention during initial antegrade cardioplegia delivery. The volume of cardioplegia required for asystole was recorded. Fifty-eight patients aged over 18 years scheduled for cardiac surgery requiring aortic cross-cl ing. There was a weak correlation of left ventricular mass and antegrade cardioplegia volume required for asystole (r = 0.35, p = 0.047). The degree of left ventricular distention correlated moderately with the severity of aortic regurgitation (r = 0.55, p = 0.007) and was excessive and stopped early (aborted) in 24% of all patients, including 18% of 39 patients without aortic regurgitation. An aortic regurgitation vena contracta of 0.3 cm predicted aborted cardioplegia with modest accuracy (AUC 0.81, 0.66-0.99, p = 0.02, sensitivity 71%, specifity 81%). Estimated left ventricular mass is not a useful predictor of the initial volume of antegrade cardioplegia required to induce asystole. However transesophageal echocardiography can predict and monitor for left ventricular distention, which is common.
Effects of realistic force feedback in a robotic assisted minimally invasive surgery system
Publisher: Informa UK Limited
Date: 12-12-2014
DOI: 10.3109/13645706.2013.867886
Abstract: Robotic assisted minimally invasive surgery systems not only have the advantages of traditional laparoscopic procedures but also restore the surgeon's hand-eye coordination and improve the surgeon's precision by filtering hand tremors. Unfortunately, these benefits have come at the expense of the surgeon's ability to feel. Several research efforts have already attempted to restore this feature and study the effects of force feedback in robotic systems. The proposed methods and studies have some shortcomings. The main focus of this research is to overcome some of these limitations and to study the effects of force feedback in palpation in a more realistic fashion. A parallel robot assisted minimally invasive surgery system (PRAMiSS) with force feedback capabilities was employed to study the effects of realistic force feedback in palpation of artificial tissue s les. PRAMiSS is capable of actually measuring the tip/tissue interaction forces directly from the surgery site. Four sets of experiments using only vision feedback, only force feedback, simultaneous force and vision feedback and direct manipulation were conducted to evaluate the role of sensory feedback from sideways tip/tissue interaction forces with a scale factor of 100% in characterising tissues of varying stiffness. Twenty human subjects were involved in the experiments for at least 1440 trials. Friedman and Wilcoxon signed-rank tests were employed to statistically analyse the experimental results. Providing realistic force feedback in robotic assisted surgery systems improves the quality of tissue characterization procedures. Force feedback capability also increases the certainty of characterizing soft tissues compared with direct palpation using the lateral sides of index fingers. The force feedback capability can improve the quality of palpation and characterization of soft tissues of varying stiffness by restoring sense of touch in robotic assisted minimally invasive surgery operations.
Correlation of selection scores with subsequent assessment scores during surgical training
Publisher: Wiley
Date: 06-05-2013
DOI: 10.1111/ANS.12176
Abstract: Determining admission criteria to select candidates most likely to succeed in surgical training in Australia and New Zealand has been an imprecise art with little empirical evidence informing decisions. Selection to the Royal Australasian College of Surgeons' Surgical Education and Training programme is based entirely on applicants' performance in structured curriculum vitae (CV), referees' reports and interviews. This retrospective review compared General Surgery (GS) trainees' performance in selection with subsequent performance in assessments during training. Data from three cohorts of GS trainees were sourced. Scores for four selection items were compared with scores from six training assessments. Interrelationships within each of the sets of selection and assessment variables were determined. A single significant relationship was found between scores on the three selection tools. High scores in the CV did not correlate with higher scores in any subsequent assessments. The structured referee report score, multi-station interview score and total selection score all correlated with performance in subsequent work-based assessments and examinations. Direct observation of procedural skills (DOPS) scores appear to reflect increasing acquisition of operative skills. Performance in mini clinical examinations (Mini-CEX) was variable, perhaps reflecting limitations of this assessment. Candidates who perform well in one examination tend to perform well in all three examinations. No selection tool demonstrated strong relationships with scores in all subsequent assessments however referee reports, multi-station interviews and total selection scores are indicators for performance in particular assessments. This may engender confidence that candidates admitted into the GS training programme are likely to progress successfully through the programme.
Translational research and the R oyal A ustralasian C ollege of S urgeons' F oundation for S urgery
Publisher: Wiley
Date: 2016
DOI: 10.1111/ANS.13385
Saphenous vein graft pseudoaneurysm formation after postoperative mediastinitis
Publisher: Elsevier BV
Date: 10-1992
DOI: 10.1016/0003-4975(92)91026-6
Abstract: Pseudoaneurysm formation involving the body of an aortocoronary saphenous vein graft is a rare event. True aneurysmal dilatation of the graft and anastomotic pseudoaneurysm formation occur more commonly. We present the case of a 73-year-old woman in whom a pseudoaneurysm communicating with the body of a posterior descending coronary artery saphenous vein graft developed, presumably after a postoperative sternal wound infection. The aneurysm was excised and the defect within the saphenous vein graft repaired using hypothermia and circulatory arrest.
AusSCORE II in predicting 30-day mortality after isolated coronary artery bypass grafting in Australia and New Zealand
Publisher: Elsevier BV
Date: 11-2014
DOI: 10.1016/J.JTCVS.2014.02.027
Abstract: To update the Australian System for Cardiac Operative Risk Evaluation (AusSCORE) model for operative estimation of 30-day mortality risk after isolated coronary artery bypass grafting in the Australian population. Data were collected by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons registry from 2001 to 2011 in 25 hospitals. A total of 31,250 patients underwent isolated coronary artery bypass grafting and the outcome was 30-day mortality. A total of 2154 (6.9%) patients had 1 or multiple missing values. Missing values were estimated assuming missing completely at random and logistic regression with a generalized estimating equation was used to address within-hospital variance. Bootstrapping methods were used to construct and validate the updated model (AusSCORE II). Also the model was validated on an out-of-creation s le of 4700 patients who underwent bypass surgery in 2012. The average age of the patients was 65.6±12.9 years and 78.6% were male. Thirteen variables were selected in the updated model. The bootstrap discrimination and calibration of the AusSCORE II was very good (receiver operating characteristics [ROC], 82.0% slope calibration, 0.987). The overall observed/AusSCORE II predicted mortality was 1.63% compared with the original AusSCORE predicted mortality of 1.01%. The validation of the AusSCORE II on the out-of-s le data also showed a high performance of the model (ROC, 84.5% Hosmer-Lemoshow P value, .7654). The AusSCORE II model provides improved prediction of 30-day mortality and successfully stratifies patient risk. The model will be useful to improve the preoperative consultation regarding risk stratification in terms of 30-day mortality.
Predictors of perioperative morbidity and mortality in lung volume reduction surgery
Publisher: Elsevier BV
Date: 06-2000
DOI: 10.1016/S0003-4975(00)01270-4
Abstract: Selection criteria for lung volume reduction surgery are still being refined. We sought to determine whether preoperative features could be used to predict early morbidity or mortality. We reviewed preoperative characteristics of the first 89 patients who underwent lung volume reduction surgery at the Alfred Hospital. Data included arterial blood gases, prednisolone use, pulmonary function tests, 6-minute walk test, and anesthetic time. Length of stay and reintubation for respiratory failure were used as markers of morbidity. Findings included PaCO2 of 43 +/- 0.7 mm Hg, PaO2 70 +/- 1.1 mm Hg, percent predicted values for forced expiratory volume in 1 second 29.6% +/- 0.8%, TLCO% predicted 35.2 +/- 1.4%, and 6-minute walk test of 315 +/- 10.6 m (mean +/- SEM). Mean length of stay was 19 +/- 2 days, with 17 (19%) patients reintubated for respiratory failure. Mortality rate was 5.6% at 1 year post surgery, with no deaths in patients less than 65 years old. Multivariate analysis revealed that length of stay, reintubation and mortality were predicted by age and surgical time (p < 0.05), with no correlation with any other variables tested. Age greater than 70 years was associated with a significant risk of mortality (OR 9.0 p = 0.04). Age greater than 70 years and anesthetic time greater than 210 minutes predict both perioperative morbidity and mortality.
The Immediate Impact of Targeted Exercises on Voice Characteristics in Female Speakers With Phonotraumatic Vocal Fold Lesions
Publisher: Elsevier BV
Date: 02-2022
DOI: 10.1016/J.JVOICE.2022.01.008
Abstract: To examine the immediate impact of 30 minutes of targeted voice exercises on measures of vocal function and lesion characteristics in female speakers with phonotraumatic vocal fold lesions (PVFLs). Prospective cohort study. Twenty-nine (n = 29) female subjects with PVFLs completed a 30 minutes targeted voice exercise protocol and a multidimensional voice analysis was conducted immediately pre and post-exercise. Analysis included expert perceptual evaluation of connected speech and stroboscopy recordings, instrumental analysis by selected aerodynamic and acoustic parameters, and self-ratings of effort and vocal function by participants. The direction and magnitude of the change from pre- to post-exercise for each in idual across parameters was assessed against a Minimal Clinically Important Difference criteria. Variability was observed among participants in their response to exercise and across parameters. Multidirectional change in function was demonstrated across instrumental parameters, with observations of both improvement and decline. The most consistent change observed was a reduced PTP post-exercises for 38% of participants (n = 11), and the greatest magnitude of change was observed in aerodynamic measures of airflow and pressure, and the acoustic parameter semitone range. Variability in the direction of change across instrumental measures was observed for 24% of participants (n = 7), while consistent improved function was seen for 45% (n = 13), declined function for 17% (n = 5) and no change for 14% (n = 4). Participant's self-reported effort and function post-exercise was also multidirectional, with the greatest number reporting improvement. Comparatively little change was observed in perceptual evaluation of speech and stroboscopy recordings. Findings suggest that in iduals with all lesion types, sizes and liabilities have the potential to improve vocal function immediately post-exercises according to instrumental measures, with the greatest magnitude of change observed in participants with large lesions. Although participants' characteristics did not differentiate, those with nodules or polyps tended to report improvement in function and reduced effort post-exercise, whereas those with a diagnosis of pseudocyst/s or a unilateral lesion appeared to report no change or declined function. Change in measures of vocal function was observed in female speakers with PVFLs immediately following a 30 minutes targeted exercises protocol. Many demonstrated improvement but a high degree of variability was observed in the way speakers respond, and it is likely an in idual's response is influenced by a range of factors. Self-rating scales, along with key instrumental parameters sensitive to the presence of PVFLs, may prove most useful in tracking initial change in the immediate and short-term duration in this population, and in assessing stimulability and candidacy for therapy. Further exploration is warranted of stimulability for immediate and cumulative change to achieve sustained improvement in function and efficiency across time.
Editorial comment. The EuroSCORE risk stratification system in the current era: how accurate is it and what should be done if it is inaccurate?
Publisher: Oxford University Press (OUP)
Date: 2009
Training in mitral valve surgery need not affect early outcomes and midterm survival: A multicentre analysis
Publisher: Oxford University Press (OUP)
Date: 03-2011
DOI: 10.1016/J.EJCTS.2011.02.003
Abstract: Mitral valve surgery may be regarded as less favourable for training, due to greater mortality risk, technical complexity, and difficulty for the supervisor to observe. We examined this perception by reviewing a multicentre experience. We analysed a multicentre database over a 7-year period containing 2216 isolated and combined mitral procedures. Of these, 2048 were performed by consultants and 168 by trainees (92% vs 8%) of varying seniority. Preoperative characteristics, early postoperative outcomes and 6-year survival were compared between groups. Propensity-score matching was performed to correct for group differences. Trainees were less likely to operate on patients, who had previously undergone coronary surgery (consultant 4.3% vs trainee 1.2%, p=0.043) and those with moderate to severe mitral regurgitation (86% vs 81%, p=0.012). There were no other statistically significant differences in preoperative variables, such as urgency, endocarditis and left-ventricular dysfunction. There were similar rates of mitral valve repair (48% vs 51%, p=0.48). Trainees were more likely to operate on rheumatic valve pathology (20% vs 28%, p=0.012). Intra-operatively, trainees had longer aortic cross-cl times (119 ± 52 vs 136 ± 50 min, p=0.0001). At 30 days, mortality was comparable (4.5% vs 3.6%, p=0.56) with a trend towards higher any mortality/morbidity in consultant procedures (33% vs 26%, p=0.059). At 6 years, survival was similar (79 ± 1.4% vs 78 ± 4.0%, p=0.73). After derivation of 142 propensity-score-matched patient pairs, trainees cases still experienced longer cross-cl times (121 ± 58 vs 137 ± 52 min, p=0.023), but there was similar 30-day mortality (4.2% vs 3.5%, p>0.99) and any mortality/morbidity (28% vs 24%, p=0.52). Six-year survival between matched pairs was also similar (74 ± 7.2% vs 80 ± 4.4%, p=0.64). Trainee status did not predict early or late adverse events after multivariate Cox regression with and without propensity-score adjustment. Trainee outcomes are not inferior even when corrected for risk. This suggests that excellent operative training and supervision can be achieved in mitral valve surgery.
Cardiac transplantation for probable cocaine-related cardiomyopathy and retransplantation after biventricular support
Publisher: Elsevier BV
Date: 04-1993
A Transparent Teleoperated Robotic Surgical System with Predictive Haptic Feedback and Force Modelling
Publisher: MDPI AG
Date: 13-12-2022
DOI: 10.3390/S22249770
Abstract: In recent years, robotic minimally invasive surgery has transformed many types of surgical procedures and improved their outcomes. Implementing effective haptic feedback into a teleoperated robotic surgical system presents a significant challenge due to the trade-off between transparency and stability caused by system communication time delays. In this paper, these time delays are mitigated by implementing an environment estimation and force prediction methodology into an experimental robotic minimally invasive surgical system. At the slave, an exponentially weighted recursive least squares (EWRLS) algorithm estimates the respective parameters of the Kelvin–Voigt (KV) and Hunt–Crossley (HC) force models. The master then provides force feedback by interacting with a virtual environment via the estimated parameters. Palpation experiments were conducted with the slave in contact with polyurethane foam during human-in-the-loop teleoperation. The experimental results indicated that the prediction RMSE of error between predicted master force feedback and measured slave force was reduced to 0.076 N for the Hunt–Crossley virtual environment, compared to 0.356 N for the Kelvin–Voigt virtual environment and 0.560 N for the direct force feedback methodology. The results also demonstrated that the HC force model is well suited to provide accurate haptic feedback, particularly when there is a delay between the master and slave kinematics. Furthermore, a haptic feedback approach that incorporates environment estimation and force prediction improve transparency during teleoperation. In conclusion, the proposed bilateral master–slave robotic system has the potential to provide transparent and stable haptic feedback to the surgeon in surgical robotics procedures.
Cellular neural network based deformation simulation with haptic force feedback
Publisher: IEEE
Date: 2006
Nanorobots for Laparoscopic Cancer Surgery
Publisher: IEEE
Date: 2007
A reaction-diffusion methodology for soft object simulation
Publisher: ACM
Date: 14-06-2006
Outcomes of coronary artery bypass grafting: A 3 year analysis using the Society of Thoracic Surgeons Database
Publisher: Elsevier BV
Date: 05-2000
DOI: 10.1046/J.1444-2892.2000.009001005.X
Abstract: Accurate risk factor analysis is a critical element in contemporary cardiac surgical practice. In the USA, the Society of Thoracic Surgeons Database allows institutions and in idual surgeons to carry out detailed patient risk assessment and to review their cardiac surgical outcomes in a comparative fashion. To evaluate outcomes of isolated coronary artery bypass grafting, data from all patients operated upon at the Alfred Hospital, Melbourne, Australia, over a 3 year period were entered into the Society of Thoracic Surgeons Database. Our results (mortality and morbidity) compared favourably with those contained within this large international database. It is hoped that a similar Australasian database can be established to facilitate a meaningful local risk assessment and a comparative analysis of outcomes of cardiac surgical procedures.
Get prepared for unexpected disasters via advanced analytics and simulation techniques for urban hydraulic engineering and water infrastructure
Publisher: IWA Publishing
Date: 10-2023
Soft Tissue Characterisation Using a Force Feedback-Enabled Instrument for Robotic Assisted Minimally Invasive Surgery Systems
Publisher: Springer Netherlands
Date: 2014
Experience with unipolar radiofrequency ablation for atrial fibrillation
Publisher: Wiley
Date: 16-08-2006
DOI: 10.1111/J.1445-2197.2006.03865.X
Abstract: The cut and sew Cox maze procedure for atrial fibrillation (AF), although effective, is not widely used because of technical complexity, prolonged duration and significant risk of postoperative bleeding. This study reviews our experience with the unipolar radiofrequency ablation (RFA) procedure, which was used to create a modified maze to treat AF. A retrospective review of 31 patients undergoing consecutive cardiac surgery who had concomitant RFA for AF over a 16-month period was carried out. A Cobra unipolar RFA probe (EPT Boston Scientific, San Jose, CA, USA) was used to create a standard set of lesions. There were 20 men and 11 women (mean age, 66 +/- 9 years range, 48-87 years). AF was continuous in 21 patients and intermittent in 10. The median duration of AF leading up to surgery was 48 months (range, 6 months-20 years). Left atrium was enlarged in 81% of the patients. Operations included mitral valve repair (7 patients), replacement (5), coronary artery bypass (10), aortic valve replacement (1) and combined procedures (8). There were no complications directly attributable to RFA. There were three early deaths. One patient required a permanent pacemaker. Median follow up was 22 months (range, 12-30 months). One patient died 2 years after the operation from a stroke. Cardioversion was attempted in five patients within 3 months of operation and was successful in four. At 2 years following the procedure, the probability of the patient remaining in sinus rhythm was 0.71 +/- 0.15. Surgical RFA can be carried out as a useful adjunct to conventional cardiac surgery. Although the results were satisfactory in this series, further studies are needed to refine the indication of the procedure and to assess its longer-term efficacy.
Measuring Vocal Function in Professional Music Theater Singers: Construct Validation of the Evaluation of the Ability to Sing Easily (EASE)
Publisher: S. Karger AG
Date: 2014
DOI: 10.1159/000366202
Abstract: b i Overview: /i /b Working music theater singers (MTS) typically have a heavy vocal load and little is known about their perception of vocal function. The Evaluation of the Ability to Sing Easily (EASE) was used to assess professional MTS' perceptions of current singing voice status and to compare scores across demographic and performance characteristics and to evaluate the construct validity of the EASE and its subscales (VF = Vocal Fatigue, PRI = Pathologic-Risk Indicators). b i Methods: /i /b Professional MTS (n = 284) completed an online survey including the EASE and two additional Vocal Concern (VC) items. Scores were compared across age, gender, whether currently working, role, perceived vocal load over the past 24 h and self-reported voice problem. b i Results: /i /b For the whole cohort, statistically significant differences were found on all subscales according to whether or not singers perceived themselves to have a voice problem (p 0.001). Currently performing singers were significantly different from those not performing in a show on the EASE Total (p = 0.014) and VF (p = 0.002), but not for PRI and VC. In the currently performing singer group, significant differences were found for gender, role and perceived voice problem on the EASE Total and all subscales (p 0.01). Significantly higher VF scores were recorded for singers with heavy vocal load (p = 0.01), but there were no differences on the EASE Total (p = 0.57), PRI (p = 0.19) or VC subscales (p = 0.53). Among these performing singers, no significant age differences were found for any EASE subscales. b i Conclusions: /i /b These findings provide further validation of the EASE as a useful tool for measuring singers' perceptions of vocal function and suggest that the subscales should be scored separately. Future evaluation of the EASE against objective clinical assessments (e.g., videostroboscopy) is recommended. © 2014 S. Karger AG, Basel
Contemporary Results Show Repeat Coronary Artery Bypass Grafting Remains a Risk Factor for Operative Mortality
Publisher: Elsevier BV
Date: 05-2009
DOI: 10.1016/J.ATHORACSUR.2009.02.006
Abstract: Reoperative coronary artery bypass grafting (redo CABG) shows improving outcomes, but with varying degrees of improvement. We assessed contemporary outcomes after redo CABG to determine if redo status is still a risk factor for early postoperative complications and midterm survival. Isolated CABG procedures (June 1, 2001 to May 31, 2008) within the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database were included. Redo status as a predictor for early outcomes was assessed with logistic regression analysis. Midterm survival was determined from the National Death Index. Effect of redo status on midterm survival was assessed using a Cox proportional hazards model. Inclusion criteria were met by 13,436 patients, and 458 (3.4%) underwent redo CABG. Operative mortality was 4.8% for redo CABG and 1.8% for first-time CABG (p < 0.001). After adjustment, redo status remained a predictor for operative mortality (odds ratio [OR], 2.1 95% confidence interval [CI], 1.3 to 3.6), myocardial infarction (OR, 2.8 95% CI, 1.6 to 6.0), and prolonged ventilation (OR, 1.5 95% CI, 1.1 to 2.0). Unadjusted survival was lower for the redo CABG group vs the first-time CABG group at up to 6 years (p = 0.01, log-rank test. After adjusting for differences in patient variables, redo status was not a predictor of midterm survival (OR, 1.03 95% CI, 0.78 to 1.35 p = 0.85). Early postoperative outcomes of redo CABG are encouraging. Midterm survival is excellent however, redo remains a significant risk factor for operative mortality in contemporary practice.
Transfusion practice varies widely in cardiac surgery: Results from a national registry
Publisher: Elsevier BV
Date: 05-2014
DOI: 10.1016/J.JTCVS.2013.10.051
Abstract: Evidence is accumulating of adverse outcomes associated with transfusion of blood components. If there are differences in perioperative transfusion rates in cardiac surgery, and what hospital factors may contribute, requires further investigation. Analysis of 42,743 adult patients who underwent 43,482 procedures from 2005 to 2011 at 25 Australian hospitals, according to the Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database. Multiple logistic regression examined associations of patient and hospital characteristics with transfusion of ≥1 red blood cell (RBC) unit platelet (PLT), fresh frozen plasma (FFP), and cryoprecipitate (CRYO) doses and ≥5 RBC units, from surgery until hospital discharge. Procedures included 24,222 (55%) isolated coronary artery bypass grafts, 7299 (17%) isolated valve, 4714 (11%) coronary artery bypass graft and valve, and 7247 (17%) other procedures. After adjustment for various patient and procedure characteristics, transfusion rates varied across hospitals for ≥1 RBC unit from 22% to 67%, ≥5 RBC units from 5% to 25%, ≥1 PLT dose from 11% to 39%, ≥1 FFP dose from 11% to 48% and ≥1 CRYO dose from 1% to 20%. Hospital characteristics, including state or territory, private versus public, and teaching versus nonteaching, were not associated with variation in transfusion rates. Variation in transfusion of all components and large volume RBC was identified, even after adjustment for patient and procedural factors known to influence transfusion, and this was not explained by hospital characteristics.
Massive hyperkalemia during combined heart-lung transplantation: Inadvertent contamination with modified euro-collins solution
Publisher: Elsevier BV
Date: 10-1992
DOI: 10.1016/1053-0770(92)90104-F
Abstract: To determine the suitability of a single-layer continuous technique for intestinal anastomosis in a surgical training program. Several recent reports have advocated the use of a continuous single-layer technique for intestinal anastomosis. Purported advantages include shorter time for construction, lower cost, and perhaps a lower rate of anastomotic leakage. The authors hypothesized that the single-layer continuous anastomosis could be safely introduced into a surgical training program and that it could be performed in less time and at a lower cost than the two-layer interrupted anastomosis. The study was conducted during a 3-year period ending September 1999. All adult patients requiring intestinal anastomosis were considered eligible. Patients who required anastomosis to the stomach, duodenum, and rectum were excluded. Patients were also excluded if the surgeon did not believe either technique could be used. Patients were randomly assigned to one- or two-layer techniques. Single-layer anastomoses were performed with a continuous 3-0 polypropylene suture. Two-layer anastomoses were constructed using interrupted 3-0 silk Lembert sutures for the outer layer and a continuous 3-0 polyglycolic acid suture for the inner layer. The time for anastomosis began with the placement of the first stitch and ended when the last stitch was cut. Anastomotic leak was defined as radiographic demonstration of a fistula or nonabsorbable material draining from a wound after oral administration, or visible disruption of the suture line during reexploration. Sixty-five single-layer and 67 two-layer anastomoses were performed. The groups were evenly matched according to age, sex, diagnosis, and location of the anastomosis. Two leaks (3.1%) occurred in the single-layer group and one (1.5%) in the two-layer group. Two abscesses (3.0%) occurred in each group. A mean of 20.8 minutes was required to construct a single-layer anastomosis versus 30.7 minutes for the two-layer technique. Mean length of stay was 7.9 days for single-layer patients and 9.9 days for two-layer patients this difference did not quite reach statistical significance. Cost of materials was $4.61 for the single-layer technique and $35.38 for the two-layer method. A single-layer continuous anastomosis can be constructed in significantly less time and with a similar rate of complications compared with the two-layer technique. It also costs less than any other method and can be incorporated into a surgical training program without a significant increase in complications.
Managing deep sternal wound infections with vacuum-assisted closure
Publisher: Wiley
Date: 31-03-2008
DOI: 10.1111/J.1445-2197.2008.04467.X
Abstract: Deep sternal wound infection is an uncommon but serious complication of cardiac surgery. Currently, there is no consensus on the optimal management. Vacuum-assisted closure (VAC) has been increasingly used to facilitate wound healing. We aim to review the management of deep sternal wound infections using VAC dressing at our hospital. A retrospective review of consecutive cases of deep sternal wound infections was carried out. Median sternotomies were carried out in 2665 patients between July 2001 and June 2006. Thirty-one patients developed deep sternal wound infections (1.2%). In 26 of these patients, VAC dressing was used either as a stand-alone therapy or as an adjunct to late sternal reconstruction. Deep sternal wound infections were diagnosed on average 13 days from initial surgery. Of the patients treated with VAC dressing, 17 (65%) had stand-alone VAC therapy and 9 had VAC therapy followed by sternal reconstruction. The average duration of VAC dressing in the two groups were 21 and 13 days respectively. There were seven in-hospital deaths, six in the stand-alone VAC group and one death from a reconstructive patient who did not have VAC therapy. The length of hospital stay was similar in two VAC groups (37 vs 45 days). Median follow up was 17 months. No late relapse was found in the stand-alone group. In the intermediate therapy group, two patients had chronic wound sinuses and one patient had a wound collection. Vacuum-assisted closure dressing may be used both as a stand-alone and as an intermediate therapy for deep sternal wound infection. Reconstructive surgery may be avoided in a significant proportion of patients. No late relapse has been associated with VAC use.
Initial Australian experience with the Thoratec ventricular assist device
Publisher: Elsevier BV
Date: 08-1992
Imagining a continuing interprofessional education program (CIPE) within surgical training.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2009
DOI: 10.1002/CHP.20034
Abstract: In recent years increasing attention has been paid to issues of professionalism in surgery and the content and structure of continuing professional development for surgeons however, little attention has been paid to interprofessional education (IPE) in surgical training. Imagining the form(s) of IPE and/or continuing interprofessional education (CIPE) programs within surgical training requires serious attention to 2 fundamental issues--the discourses of professionalism in surgery and the professional culture of surgery, as shaped and expressed within the clinical setting. We explore the possibility that concepts of professionalism within surgery may be in conflict with the tenets of interprofessionalism held by other health and medical professionals. We believe that if any rapprochement is to occur between the concept of professionalism in surgical training (and within the everyday clinical culture of surgical subspecialties groups and their professional institutions) and broader discourses of interprofessionalism circulating within health care institutions, there is a pressing need to understand and deconstruct this conflict from the point of view of surgery.
Pattern of activin A and follistatin release in a sheep model of cardiopulmonary bypass
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.CYTO.2011.01.001
Abstract: Activin A, a member of transforming growth factor-β superfamily, has been established as a critical cytokine released early in endotoxemia and other inflammatory syndromes. The release of activin A and its binding protein, follistatin during cardiopulmonary bypass (CPB) has not been previously reported. Our study aimed to define the pattern of activin A and follistatin release in a sheep CPB model. Control group consisted of left thoractomy alone (n=6). CPB was performed using either unfractionated heparin (n=6) or lepirudin (n=6) as anticoagulant. Unlike heparin, lepirudin does not cause activin A and follistatin release on its own. Serum s les were assayed for activin A, follistatin, tumour necrosis factor-α and interleukin-6. Compared with the control group, CPB using lepirudin was associated with a biphasic release of activin A. The first peak occurred within the first hour of CPB and a second peak occurred within the early post-operative period, coincident with a large release of follistatin. Close correlation was found between follistatin and IL-6 in the control and lepirudin groups, indicative of a role for follistatin in the acute phase response. In contrast to the control and lepirudin groups, CPB using heparin resulted in a concurrent release of activin A and follistatin. CPB is a trigger for the release of biologically-active free activin A into the circulation, at levels considerably greater than that induced by surgery alone. Triggering release of this critical inflammatory cytokine suggests that activin A may contribute to the adverse outcomes associated with systemic inflammation in cardiac surgery.
ANZSCTS President's Address 2012
Publisher: Elsevier BV
Date: 06-2013
Mitral valve replacement via a right mini-thoracotomy in the dog: Use of carbon dioxide to reduce intracardiac air
Publisher: Oxford University Press (OUP)
Date: 06-1997
DOI: 10.1016/S1010-7940(97)01219-0
Abstract: To develop a clinically applicable method of minimally invasive mitral valve replacement (MVR) with cardioplegia, and examine the ability of carbon dioxide (CO2) to improve de-airing. MVR was performed via a 5 x 3-cm right lateral minithoracotomy in eight greyhounds. Peripheral cardiopulmonary bypass and an ascending aortic balloon catheter (endoaortic cl ) were used for cardioplegia and aortic root venting. The endoaortic cl was inflated in the ascending aorta under fluoroscopy and cardioplegic solution was infused. In four dogs, CO2 at 2 l/min was used to displace air in the chest. A left atriotomy was made, the valve exposed and a mechanical valve implanted. After left atrial closure, retained intracardiac gas was aspirated from the aortic root and collected in a bubble-trap. The endocl was deflated and the animal weaned from bypass. A satisfactory MVR was performed in all cases. The cl time was 64 +/- 13 min and all dogs were stable post-bypass. In the CO2 group, intrathoracic CO2 was maintained above 86% and 0.1 +/- 0.1 ml of gas was collected, compared to 1.3 +/- 0.8 ml in the non-CO2 group (P < 0.05). Femoro-femoral bypass and use of the endoaortic cl allow a safe and efficacious MVR via a right minithoracotomy in the dog. A high intrathoracic CO2 concentration reduces the amount of retained intracardiac gas.
Acute Risk Change for Cardiothoracic Admissions to Intensive Care (ARCTIC index): A new measure of quality in cardiac surgery
Publisher: Elsevier BV
Date: 12-2014
DOI: 10.1016/J.JTCVS.2014.06.069
Abstract: Quality of cardiac surgical care may vary between institutions. Mortality is low and large numbers are required to discriminate between hospitals. Measures other than mortality may provide better comparisons. To develop and assess the Acute Risk Change for Cardiothoracic Admissions to Intensive Care (ARCTIC) index, a new performance measure for cardiothoracic admissions to intensive care units (ICUs). The Australian and New Zealand Society of Cardiac and Thoracic Surgeons database and Australian and New Zealand Intensive Care Society Adult Patient Database were linked. Logistic regression was used to generate a predicted risk of death first from preoperative data using the previously validated Allprocscore and second on admission to an ICU using Acute Physiology and Chronic Health Evaluation III score. Change in risk as a percentage (ARCTIC) was calculated for each patient. The validity of ARCTIC as a marker of quality was assessed by comparison with intraoperative variables and postoperative morbidity markers. Sixteen thousand six hundred eighty-seven patients at 21 hospitals from 2008 to 2011 were matched. An increase in ARCTIC score was associated with prolonged cardiopulmonary bypass time (P = .001), intraoperative blood product transfusion (P < .001), reoperation (P < .0001), postoperative renal failure (P < .0001), prolonged ventilation (P < .0001), and stroke (P = .001). The ARCTIC index is associated with known markers of perioperative performance and postoperative morbidity. It may be used as an overall marker of quality for cardiac surgery. Further work is required to assess ARCTIC as a method to discriminate between cardiac surgical units.
A Cellular Neural Network Methodology for Deformable Object Simulation
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 10-2006
Abstract: This paper presents a new methodology to simulate soft object deformation by drawing an analogy between a cellular neural network (CNN) and elastic deformation. The potential energy stored in an elastic body as a result of a deformation caused by an external force is propagated among mass points by a nonlinear CNN. The novelty of the methodology is that: 1) CNN techniques are established to describe the potential energy distribution of the deformation for extrapolating internal forces and 2) nonlinear materials are modeled with nonlinear CNNs rather than geometric nonlinearity. Integration with a haptic device has been achieved for deformable object simulation with force feedback. The proposed methodology not only predicts the typical behaviors of living tissues, but it also accommodates isotropic, anisotropic, and inhomogeneous materials, as well as local and large-range deformation.
Dynamic motion analysis of dart throwers motion visualized through computerized tomography and calculation of the axis of rotation
Publisher: SAGE Publications
Date: 25-10-2013
Abstract: We used a dynamic three-dimensional (3D) mapping method to model the wrist in dynamic unrestricted dart throwers motion in three men and four women. With the aid of precision landmark identification, a 3D coordinate system was applied to the distal radius and the movement of the carpus was described. Subsequently, with dynamic 3D reconstructions and freedom to position the camera viewpoint anywhere in space, we observed the motion pathways of all carpal bones in dart throwers motion and calculated its axis of rotation. This was calculated to lie in 27° of anteversion from the coronal plane and 44° of varus angulation relative to the transverse plane. This technique is a safe and a feasible carpal imaging method to gain key information for decision making in future hand surgical and rehabilitative practices.
Validity of a screening tool for detecting subtle cognitive impairment in the middle-aged and elderly
Publisher: Informa UK Limited
Date: 12-2014
DOI: 10.2147/CIA.S68363
Regulation and actions of activin A and follistatin in myocardial ischaemia–reperfusion injury
Publisher: Elsevier BV
Date: 10-2014
DOI: 10.1016/J.CYTO.2014.06.017
Abstract: Activin A, a member of the transforming growth factor-β superfamily, is stimulated early in inflammation via the Toll-like receptor (TLR) 4 signalling pathway, which is also activated in myocardial ischaemia-reperfusion. Neutralising activin A by treatment with the activin-binding protein, follistatin, reduces inflammation and mortality in several disease models. This study assesses the regulation of activin A and follistatin in a murine myocardial ischaemia-reperfusion model and determines whether exogenous follistatin treatment is protective against injury. Myocardial activin A and follistatin protein levels were elevated following 30 min of ischaemia and 2h of reperfusion in wild-type mice. Activin A, but not follistatin, gene expression was also up-regulated. Serum activin A did not change significantly, but serum follistatin decreased. These responses to ischaemia-reperfusion were absent in TLR4(-/-) mice. Pre-treatment with follistatin significantly reduced ischaemia-reperfusion induced myocardial infarction. In mouse neonatal cardiomyocyte cultures, activin A exacerbated, while follistatin reduced, cellular injury after 3h of hypoxia and 2h of re-oxygenation. Neither activin A nor follistatin affected hypoxia-reoxygenation induced reactive oxygen species production by these cells. However, activin A reduced cardiomyocyte mitochondrial membrane potential, and follistatin treatment ameliorated the effect of hypoxia-reoxygenation on cardiomyocyte mitochondrial membrane potential. Taken together, these data indicate that myocardial ischaemia-reperfusion, through activation of TLR4 signalling, stimulates local production of activin A, which damages cardiomyocytes independently of increased reactive oxygen species. Blocking activin action by exogenous follistatin reduces this damage.
An optimal parameter estimation method for soft tissue characterization
Publisher: IEEE
Date: 08-2010
Developing an integrated training pathway for clinical academics: notes from the first binational summit meeting
Publisher: Wiley
Date: 06-2015
DOI: 10.1111/ANS.13119
Post-operative management of the lung transplant patient
Publisher: Informa UK Limited
Date: 10-1995
Coenzyme Q10 therapy before cardiac surgery improves mitochondrial function and in vitro contractility of myocardial tissue
Publisher: Elsevier BV
Date: 2005
DOI: 10.1016/J.JTCVS.2004.03.034
Abstract: Previous clinical trials suggest that coenzyme Q(10) might afford myocardial protection during cardiac surgery. We sought to measure the effect of coenzyme Q(10) therapy on coenzyme Q(10) levels in serum, atrial trabeculae, and mitochondria to assess the effect of coenzyme Q(10) on mitochondrial function to test the effect of coenzyme Q(10) in protecting cardiac myocardium against a standard hypoxia-reoxygentation stress in vitro and to determine whether coenzyme Q(10) therapy improves recovery of the heart after cardiac surgery. Patients undergoing elective cardiac surgery were randomized to receive oral coenzyme Q(10) (300 mg/d) or placebo for 2 weeks preoperatively. Pectinate trabeculae from right atrial appendages were excised, and mitochondria were isolated and studied. Trabeculae were subjected to 30 minutes of hypoxia, and contractile recovery was measured. Postoperative cardiac function and troponin I release were assessed. Patients receiving coenzyme Q(10) (n = 62) had increased coenzyme Q(10) levels in serum (P = .001), atrial trabeculae (P = .0001), and isolated mitochondria (P = .0002) compared with levels seen in patients receiving placebo (n = 59). Mitochondrial respiration (adenosine diphosphate/oxygen ratio) was more efficient (P = .012), and mitochondrial malondialdehyde content was lower (P = .002) with coenzyme Q(10) than with placebo. After 30 minutes of hypoxia in vitro, pectinate trabeculae isolated from patients receiving coenzyme Q(10) exhibited a greater recovery of developed force compared with those in patients receiving placebo (46.3% +/- 4.3% vs 64.0% +/- 2.9%, P = .001). There was no between-treatment difference in preoperative or postoperative hemodynamics or in release of troponin I. Preoperative oral coenzyme Q(10) therapy in patients undergoing cardiac surgery increases myocardial and cardiac mitochondrial coenzyme Q(10) levels, improves mitochondrial efficiency, and increases myocardial tolerance to in vitro hypoxia-reoxygenation stress.
Australasian Society of Cardiac and Thoracic Surgeons Registry of Circulatory Support Devices 1989-1994
Publisher: Elsevier BV
Date: 12-1996
Robust adaptive motion tracking control of piezoelectric actuation systems for micro/nano manipulation
Publisher: IEEE
Date: 04-2007
A Cellular Neural Network for Deformable Object Modelling
Publisher: Springer US
Date: 2006
Interprofessional non-technical skills for surgeons in disaster response: A literature review
Publisher: Informa UK Limited
Date: 10-06-2013
DOI: 10.3109/13561820.2013.791670
Abstract: Natural disasters impose a significant burden on society. Current disaster training programmes do not place an emphasis on equipping surgeons with non-technical skills for disaster response. This literature review sought to identify non-technical skills required of surgeons in disaster response through an examination of four categories of literature: "disaster" "surgical" "organisational management" and "interprofessional". Literature search criteria included electronic database searches, internet searches, hand searching, ancestry searching and networking strategies. Various potential non-technical skills for surgeons in disaster response were identified including: interpersonal skills such as communication, teamwork and leadership cognitive strategies such flexibility, adaptability, innovation, improvisation and creativity physical and psychological self-care conflict management, collaboration, professionalism, health advocacy and teaching. Such skills and the role of interprofessionalism should be considered for inclusion in surgical disaster response training course curricula.
The Impact of a Vocal Loading Task on Voice Characteristics of Female Speakers With Benign Vocal Fold Lesions
Publisher: Elsevier BV
Date: 12-2021
Effects of amadumbe starch nanocrystals on the physicochemical properties of starch biocomposite films
Publisher: Elsevier BV
Date: 06-2017
DOI: 10.1016/J.CARBPOL.2017.02.041
Abstract: The influence of amadumbe starch nanocrystals (SNCs) at varying concentrations (2.5, 5 and 10%) on the physicochemical properties of biocomposite films prepared using two starch matrices, amadumbe and potato starches were investigated. Amadumbe SNCs exhibited square-like platelets morphology, typical of SNC derived from A-type starches. In general, the inclusion of SNCs significantly decreased water vapour permeability (WVP) of composite films whilst thermal stability and opacity were increased. Amadumbe starch films showed substantially high tensile strength (TS) compared to potato starch in the presence of SNCs. At 2.5% SNCs, TS of composite amadumbe film (8MPa) was about four times that of composite potato films. However, SNCs≥5% generally decreased TS of both potato and amadumbe films. Amadumbe SNCs can potentially be used as fillers to improve the properties of biodegradable starch films. Amadumbe starch has better film forming properties compared to potato starch.
Compensation and calibration of gravitational forces in a force-feedback enabled surgical robot
Publisher: IEEE
Date: 07-2013
Does patient gender affect outcomes after concomitant coronary artery bypass graft and aortic valve replacement? An Australian society of cardiac and thoracic surgeons database study
Publisher: S. Karger AG
Date: 2011
DOI: 10.1159/000330133
Abstract: i Objectives: /i Women undergoing isolated coronary artery bypass graft (CABG) surgery have been previously shown to be at an independently increased risk for post-operative morbidity and mortality. However, there are considerably less data on whether this trend remains true in patients undergoing concomitant aortic valve replacement (AVR) and CABG surgery. The aim of our study was to investigate this pertinent issue. i Methods: /i Data obtained between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Program were retrospectively analysed. Demographic, operative data and post-operative complications were compared between male and female patients using χ sup /sup and t tests. Long-term survival analysis was performed using Kaplan-Meier survival curves and the log-rank test. Independent risk factors for short- and long-term mortality were identified using binary logistic and Cox regression, respectively. i Results: /i Concomitant AVR and CABG surgery was undertaken in 2,563 patients 31.8% were female. Female patients were older (mean age 76 vs. 73 years p 0.001) and presented more often with hypertension (p 0.001) but less often with severely impaired ejection fraction (p 0.001), peripheral vascular disease (p 0.001) and triple vessel disease (p 0.001). Women did not demonstrate an increased risk of 30-day mortality (4.8 vs. 3.3%) on univariate (p = 0.069) or multivariate (p = 0.236) analysis. Female gender was independently associated with post-operative myocardial infarction (p = 0.022) and red blood cell transfusion (p 0.001). There was no difference in long-term survival between men and women on multivariate analysis (p = 0.413). i Conclusion: /i Female gender is not associated with poorer short- or long-term outcomes after concomitant CABG and AVR surgery.
A current review of minimally invasive cardiac surgery
Publisher: Elsevier BV
Date: 12-1996
Gastrointestinal complications after cardiac surgery: 10-year experience of a single Australian centre
Publisher: Wiley
Date: 26-03-2013
DOI: 10.1111/ANS.12134
Abstract: Gastrointestinal (GI) complications after cardiac surgery are uncommon, but are associated with high morbidity and mortality as well as significant hospital resource utilization. We analysed a prospectively collected database containing all adult cardiac surgery procedures performed from July 2001 to March 2011 at Monash Medical Centre and Jessie McPherson Private Hospital. Patients with post-operative GI complications were compared to patients without GI complications who were operated in the same period. The incidence of GI complications was 1.1% (61 out of 5382 patients) with an overall 30-day mortality of 33% (versus 3% in the non-GI complication group). The most common complications were GI bleeding, gastroenteritis and bowel ischaemia. Patients who had GI complications were significantly older, had higher incidence of renal impairment, chronic lung disease and anticoagulation therapy and were more likely to be in cardiogenic shock. Emergency procedures, combined coronary artery bypass grafting and valve surgery and aortic dissection cases were more common in the GI complication group. The GI complication group also had higher incidence of return to theatre, renal failure, stroke, septicaemia and multi-organ failure. GI complications after cardiac surgery remain an uncommon but dreadful complication associated with high mortality. Our findings should prompt a high degree of clinical vigilance in order to make an early diagnosis especially in high risk patients. Further studies aiming to identify independent predictors for GI complications after cardiac surgery are warranted.
Aspirin and Tranexamic Acid for Coronary Artery Surgery (ATACAS) Trial: rationale and design.
Publisher: Elsevier BV
Date: 02-2008
DOI: 10.1016/J.AHJ.2007.10.003
Abstract: Despite some concern that recent aspirin ingestion increases blood loss after coronary artery surgery, there is some evidence that this may reduce thrombotic complications. In contrast, antifibrinolytic drugs can reduce blood loss in this setting, but there is concern that they may increase thrombotic complications. Published guidelines are limited by a lack of large randomized trials addressing the risks and benefits of each of these commonly used therapies in cardiac surgery. The ATACAS Trial is a study comparing aspirin, tranexamic acid, or both, with placebo in patients undergoing on-pump or off-pump coronary artery surgery. We discuss the rationale for conducting ATACAS, a 4600-patient, multicenter randomized trial in at-risk coronary artery surgery, and the features of the ATACAS study design (objectives, end points, target population, allocation, treatments, patient follow-up, and analysis). The ATACAS Trial will be the largest study yet conducted to ascertain the benefits and risks of aspirin and antifibrinolytic therapy in coronary artery surgery. Results of the trial will guide the routine clinical care of patients in this setting.
A preoperative risk prediction model for 30-day mortality following cardiac surgery in an Australian cohort
Publisher: Oxford University Press (OUP)
Date: 05-2010
DOI: 10.1016/J.EJCTS.2009.11.021
Abstract: Population-specific risk models are required to build consumer and provider confidence in clinical service delivery, particularly when the risks may be life-threatening. Cardiac surgery carries such risks. Currently, there is no model developed on the Australian cardiac surgery population and this article presents a novel risk prediction model for the Australian cohort with the aim to provide a guide for the surgeons and patients in assessing preoperative risk factors for cardiac surgery. This study aims to identify preoperative risk factors associated with 30-day mortality following cardiac surgery for an Australian population and to develop a preoperative model for risk prediction. All patients (23016) undergoing cardiac surgery between July 2001 and June 2008 recorded in the Australian Society of Cardiac and Thoracic Surgeons (ASCTS) database were included in this analysis. The data were ided randomly into model creation (13810, 60%) and model validation (9206, 40%) sets. The model was developed on the creation set and then validated on the validation set. The bootstrap s ling and automated variable selection methods were used to develop several candidate models. The final model was selected from this group of candidate models by using prediction mean square error (MSE) and Bayesian Information Criteria (BIC). Using a multifold validation, the average receiver operating characteristic (ROC), p-value for Hosmer-Lemeshow chi-squared test and MSE were obtained. Risk thresholds for low-, moderate- and high-risk patients were defined. The expected and observed mortality for various risk groups were compared. The multicollinearity and first-order interaction effect between clinically meaningful risk factors were investigated. A total of 23016 patients underwent cardiac surgery and the 30-day mortality rate was 3.2% (728 patients). Independent predictors of mortality in the model were: age, sex, the New York Heart Association (NYHA) class, urgency of procedure, ejection fraction estimate, lipid-lowering treatment, preoperative dialysis, previous cardiac surgery, procedure type, inotropic medication, peripheral vascular disease and body mass index (BMI). The model had an average ROC 0.8223 (95% confidence interval (CI): 0.8118-0.8227), p-value 0.8883 (95% CI: 0.8765-0.90) and MSE 0.0251 (95% CI: 0.02515-0.02516). The validation set had observed mortality 3.0% (95% CI: 2.7-3.3%) and predicted mortality 2.9% (95% CI: 2.6-3.2%). The low-risk group (additive score 0-3) had 0.6% observed mortality (95% CI: 0.3-0.9%) and 0.5% predicted mortality (95% CI: 0.2-0.8%). The moderate-risk group (additive score 4-9) had 1.7% observed mortality (95% CI: 1.2-2.2%) and 1.4% predicted mortality (95% CI: 1.0-1.8%). The observed mortality for the high-risk group (additive score 9 plus) was 6.7% (95% CI: 5.8-7.6%) and the expected mortality was 6.7% (95% CI: 5.8-7.6%). A preoperative risk prediction model for 30-day mortality was developed for the Australian cardiac surgery population.
Impact of smoking status on outcomes after concomitant aortic valve replacement and coronary artery bypass graft surgery
Publisher: Georg Thieme Verlag KG
Date: 25-10-2014
Abstract: There is a paucity of data on the impact of smoking status on outcomes after concomitant aortic valve replacement and coronary artery bypass graft (AVR-CABG) surgery. Data obtained prospectively between June 2001 and December 2009 by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Demographic and operative data were compared between patients who were nonsmokers, previous smokers, and current smokers using chi-square test and t-test. The independent impact of smoking status on 14 short-term complications and long-term mortality was determined using binary logistic and Cox regression, respectively. Concomitant AVR-CABG surgery was performed in 2,563 patients smoking status was recorded in 2,558 (99.8%) patients. Of these, 1,052 (41.1%) patients had no previous smoking history, 1,345 (52.6%) patients were previous smokers, and 161 (6.3%) patients were current smokers. The 30-day mortality rate was 3.5% in nonsmokers, 4.1% in previous smokers, and 3.1% in current smokers (p = nonsignificant). The incidence of perioperative complications was similar in the three groups. The mean follow-up period for this study was 36 months (range, 0-105 months). After adjusting for differences in patient variables, the incidence of late mortality was higher in previous smokers (hazard ratio [HR], 1.44 95% confidence interval [CI], 1.14-1.81 p = 0.002) compared with nonsmokers. A trend toward increased late mortality in current smokers was noted (HR, 1.34 95% CI, 0.86-2.08 p = 0.201). Smoking is not associated with adverse outcomes after concomitant AVR-CABG surgery. Smoking status should not, therefore, preclude these patients from undergoing this procedure. Given the adverse effect of smoking on overall cardiovascular morbidity and mortality and late postoperative mortality, patients should be encouraged to quit smoking.
A change of heart: The new infective endocarditis prophylaxis guidelines
Publisher: Wiley
Date: 18-08-2008
DOI: 10.1111/J.1834-7819.2008.00049.X
Abstract: New Australian guidelines for the prevention of infective endocarditis were published in July 2008. The guidelines were revised by a multidisciplinary group to reflect recent changes in international recommendations regarding antibiotic prophylaxis for infective endocarditis. The reasons for the changes are explored in this review and the implications for dental practice are discussed.
Dissection of an allograft ascending aorta after aortic root replacement
Publisher: Elsevier BV
Date: 03-1996
DOI: 10.1016/0003-4975(95)00867-5
Abstract: THe case of a 57-year-old man with dissection of an allograft ascending aorta 2 months after aortic root replacement is presented. Most likely traumatic in origin, this unusual complication was managed by Dacron graft replacement of the ascending aorta using hypothermia and circulatory arrest.
A call for national e-health clinical safety governance
Publisher: AMPCo
Date: 06-2012
DOI: 10.5694/MJA12.10727
Weekend effect in emergency laparotomy: a propensity score‐matched analysis
Publisher: Wiley
Date: 07-2023
DOI: 10.1111/ANS.18595
Abstract: The ‘weekend effect’ is the term given to the observed discrepancy regarding patient care and outcomes on weekends compared to weekdays. This study aimed to determine whether the weekend effect exists within Aotearoa New Zealand (AoNZ) for patients undergoing emergency laparotomy (EL), given recent advances in management of EL patients. A cohort study was conducted across five hospitals, comparing the outcomes of weekend and weekday acute EL. A propensity‐score matched analysis was used to remove potential confounding patient characteristics. Of the 487 patients included, 132 received EL over the weekend. There was no statistically significant difference between patients undergoing EL over the weekend compared to weekdays. Mortality rates were comparable between the weekday and weekend cohorts ( P = 0.464). These results suggest that modern perioperative care practice in New Zealand obviates the ‘weekend’ effect.
ANALYSIS OF EARLY AND LATE OUTCOMES AFTER CONCOMITANT AORTIC VALVE REPLACEMENT AND CORONARY ARTERY BYPASS GRAFT SURGERY IN OCTOGENARIANS: A MULTI‐INSTITUTIONAL AUSTRALIAN STUDY
Publisher: Wiley
Date: 09-2011
Compensatory lung hypertrophy following pneumonectomy
Publisher: Elsevier BV
Date: 07-2010
An unusual tumour involving heart and liver
Publisher: Elsevier BV
Date: 04-1993
Rural surgeons' attitudes towards and usage of evidence-based medicine in rural surgical practice.
Publisher: Wiley
Date: 09-06-2011
DOI: 10.1111/J.1365-2753.2011.01695.X
Abstract: Rural and remote surgical practice presents unique barriers to the uptake of the evidence-based medicine (EBM) paradigm. As medical and education institutions around Australia develop practices and support for EBM, there are growing questions about how EBM is situated in the rural and remote context. The Monash University Department of Surgery at Monash Medical Centre implemented a study to explore the current understandings, attitudes and practices of rural surgeons towards the EBM paradigm. Descriptive survey of rural surgeons based in a tertiary care environment. The overall results of the survey demonstrate that: (1) rural surgeons have a good understanding of EBM (2) EBM evidence is somewhat useful but not very important to clinical decision making and (3) while rural surgeons are relatively confident in most sources listed, they are most confident in their own judgment and clinical practice guidelines, and least confident in telephone contact with colleagues. Rural surgeons' understanding, usage and confidence in EBM purports that rural surgeons have contradictory, ambivalent and complex views of the EBM paradigm and its place in rural surgical practice. Professional isolation and context specificity are important to consider when extending the EBM paradigm to rural surgical practice and understanding the EBM uptake in the rural surgery context.
The impact of cardiac surgery on cognition
Publisher: Wiley
Date: 17-07-2008
DOI: 10.1002/SMI.1204
Short- and midterm outcomes of coronary artery bypass surgery performed by surgeons in training
Publisher: Elsevier BV
Date: 05-2009
DOI: 10.1016/J.JTCVS.2008.10.011
Abstract: The effect of training on outcomes in cardiac surgery is poorly studied. We aimed to study the results of coronary artery bypass grafting procedures performed by surgeons in training across our state with respect to short- and midterm postoperative outcomes. All coronary artery bypass grafting surgeries performed by trainee surgeons between July 2001 and December 2006 were compared with those performed by consultant surgeons using mandatory prospectively collected statewide data. Early mortality prolonged ventilation or intensive care unit stay return to operating theater for bleeding, stroke, myocardial infarction, or renal failure and 5-year survival were compared using propensity score analysis. A total of 7745 surgeries were included in this study. Trainees performed 983 (13%) surgeries. Trainee surgeries had longer perfusion and crosscl times. Crude early postoperative outcomes were similar between trainee and consultant surgeries. After propensity score adjustment, early outcomes remained similar, with the exception of myocardial infarction (0.8% in trainee surgeries vs 0.4% in consultant surgeries, P = .046). Adjusted 1-, 3-, and 5-year survivals were similar between trainee and consultant surgeries: 95.3% versus 95.5%, 90.8% versus 92.0%, and 86.3% versus 87.1%, respectively. Coronary artery bypass grafting performed by trainee surgeons within a supervised program is safe with acceptable short- and midterm outcomes.
“The other side of the table…’: Early career gynaecological oncologists' transition from trainee to trainer
Publisher: Wiley
Date: 02-01-2023
DOI: 10.1111/AJO.13644
Abstract: The transition to consultant practice represents an important transition from the role of trainee to trainer. We used the theoretical framework of Threshold Concepts to better understand this transition by analysing data from a broader qualitative study examining the experience of early career Certified Gynaecological Oncologists (CGOs) in Australia and New Zealand. Semi‐structured interviews were conducted with CGOs of years consultant experience. Transcripts were analysed using reflexive thematic analysis, sensitised by the theoretical framework of Threshold Concepts. Seven early career CGOs were interviewed. Analysis resulted in the construction of five main themes related to the trainer role, each demonstrating characteristics of Threshold Concepts: ‘Part of becoming and being a consultant’ ‘Managing complex work environments and training responsibilities’ ‘Optimising near peer relationships’ ‘Recency informing evolution of training’ and “‘Being responsible and letting go…’ – the next transition.” The themes offer insights into the areas of the transition to trainer that are troublesome, the impact of negotiating these challenges on professional identity formation, and the strategies used by CGOs to negotiate them. Using the lens of Threshold Concepts, these experiences can be normalised, and supported through efforts to facilitate the development of skills in reflection, feedback, coaching and mentorship.
A force-sensing surgical tool with a proximally located force/torque sensor
Publisher: Wiley
Date: 26-02-2016
DOI: 10.1002/RCS.1737
Abstract: Robotic surgery has seen a rapid increase in popularity in the last few decades because advantages such as increased accuracy and dexterity can be realized. These systems still lack force-feedback, where such a capability is believed to be beneficial to the surgeon and can improve safety. In this paper a force-feedback enabled surgical robotic system is described in which the developed force-sensing surgical tool is discussed in detail. The developed surgical tool makes use of a proximally located force/torque sensor, which, in contrast to a distally located sensor, requires no miniaturization or sterilizability. Experimental results are presented, and indicate high force sensing accuracies with errors <0.09 N. It is shown that developing a force-sensing surgical tool utilizing a proximally located force/torque sensor is feasible, where a tool outer diameter of 12 mm can be achieved. For future work it is desired to decrease the current tool outer diameter to 10 mm. Copyright © 2016 John Wiley & Sons, Ltd.
Preoperative atrial fibrillation is an independent predictor of worse early and late outcomes after isolated coronary artery bypass graft surgery
Publisher: Elsevier BV
Date: 03-2015
DOI: 10.1016/J.JJCC.2014.06.003
Abstract: To evaluate the impact of preoperative atrial fibrillation (pre-op AF) on early and late mortality after isolated coronary artery bypass graft (CABG) surgery. Data obtained prospectively between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Patients who underwent concomitant atrial arrhythmia surgery/ablation were excluded. Demographic and operative data were compared between patients with and without pre-op AF. The independent association of pre-op AF on early mortality, perioperative complications, and late mortality was determined. Isolated CABG surgery was performed in 21,534 patients 1312 (6.1%) presented with pre-op AF. Pre-op AF patients were older (mean age, 71 years vs. 65 years, p<0.001) and had more comorbidities reflected in a higher additive EuroSCORE (8.4±3.5 vs. 6.5±3.2, p=0.001). Even after accounting for confounding factors, however, pre-op AF was associated with a 63% increase in 30-day mortality [4.2% vs. 1.4% hazard ratio (HR), 1.63 95% confidence interval (CI), 1.17-2.29 p=0.004] and 39% increase in late mortality (5-year survival, 78% vs. 90% HR, 1.39 95% CI, 1.20-1.61 p<0.001). Pre-op AF is an independent predictor of poor early and late outcomes. Pre-op AF should be considered, therefore, in the development or update of risk stratification models for CABG surgery.
Impact of smoking status on early and late outcomes after isolated coronary artery bypass graft surgery
Publisher: Elsevier BV
Date: 05-2013
DOI: 10.1016/J.JJCC.2013.01.002
Abstract: There are limited data on the impact of smoking status on outcomes after isolated coronary artery bypass graft (CABG) surgery. Data obtained prospectively between June 2001 and December 2009 by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Program were retrospectively analyzed. Demographic and operative data were compared between patients who were non-smokers, previous smokers, and current smokers. The independent impact of smoking status on 14 short-term complications and long-term mortality was determined using binary logistic and Cox regression, respectively. Isolated CABG surgery was performed in 21 534 patients smoking status was recorded in 21486 (99.8%). Of these, 7023 (32.6%) had no previous smoking history, 11183 (59.1%) were previous smokers, and 3290 (15.2%) were current smokers. The 30-day mortality rate was 1.8% in non-smokers, 1.5% in previous smokers, and 1.5% in current smokers (p=NS). The incidence of peri-operative complications was generally similar in the three groups, but current smokers were at an increased risk of pneumonia (p<0.001), and multisystem failure (p=0.003). The mean follow-up period for this study was 37 months (range, 0-106 months). After adjusting for differences in patient variables, the incidence of late mortality was higher in previous smokers [hazard ratio (HR), 1.73 95% confidence interval (CI), 1.47-2.05 p<0.001] or current smokers (HR, 1.41 95% CI, 1.26-1.59 p<0.001) compared to non-smokers. Smoking status is not associated with early mortality after isolated CABG. It is, however, associated with an increased risk of pulmonary complications and reduced long-term survival.
The relationship between cerebral palsy and cryptorchidism
Publisher: Elsevier BV
Date: 12-1989
DOI: 10.1016/S0022-3468(89)80572-X
Abstract: This study examined the reported association between cerebral palsy and cryptorchidism. A comparison was made among 25 boys with cerebral palsy under the age of 2 years and 6 months, 25 boys with cerebral palsy aged between 5 and 10 years, and age-matched controls. The testes remained in the same position with age in boys with cerebral palsy, whereas in normal children the testes were slightly lower initially (P less than .005) and became lower still with growth (P less than .001). This result, taken in conjunction with previous studies, casts doubts on the theories of early damage to the hypothalamic-pituitary-gonadal axis as the cause of maldescent in cerebral palsy. It is postulated that any apparent increase in cryptorchidism in older patients with cerebral palsy may be caused by spasticity of the cremaster muscle leading to pathologic retraction of the testis out of the scrotum.
Prediction of acute kidney injury within 30 days of cardiac surgery
Publisher: Elsevier BV
Date: 06-2014
DOI: 10.1016/J.JTCVS.2013.06.049
Abstract: To predict acute kidney injury after cardiac surgery. The study included 28,422 cardiac surgery patients who had had no preoperative renal dialysis from June 2001 to June 2009 in 18 hospitals. Logistic regression analyses were undertaken to identify the best combination of risk factors for predicting acute kidney injury. Two models were developed, one including the preoperative risk factors and another including the pre-, peri-, and early postoperative risk factors. The area under the receiver operating characteristic curve was calculated, using split-s le internal validation, to assess model discrimination. The incidence of acute kidney injury was 5.8% (1642 patients). The mortality for patients who experienced acute kidney injury was 17.4% versus 1.6% for patients who did not. On validation, the area under the curve for the preoperative model was 0.77, and the Hosmer-Lemeshow goodness-of-fit P value was .06. For the postoperative model area under the curve was 0.81 and the Hosmer-Lemeshow P value was .6. Both models had good discrimination and acceptable calibration. Acute kidney injury after cardiac surgery can be predicted using preoperative risk factors alone or, with greater accuracy, using pre-, peri-, and early postoperative risk factors. The ability to identify high-risk in iduals can be useful in preoperative patient management and for recruitment of appropriate patients to clinical trials. Prediction in the early stages of postoperative care can guide subsequent intensive care of patients and could also be the basis of a retrospective performance audit tool.
Evaluation of a miniature antimony electrode for measurement of myocardial pH
Publisher: Informa UK Limited
Date: 1999
Abstract: Myocardial pH reflects the metabolic status of the heart and pH monitoring is an invaluable way to monitor the efficacy of myocardial protection during cardiac surgery. We developed a miniature antimony electrode for pH measurement in the heart. We examined the sensitivity, accuracy and the effects of temperature and oxygen tension on pH readings with this electrode in standard buffers and in anaesthetized dogs. In buffers the antimony electrode exhibited a gradient of -50.3 +/- 1.8 mV pH-1 at 25 degrees C, close to the Nernstian slope and showed a high correlation with conventional glass electrode readings (mean difference 0.027 +/- 0.0035 pH, r2 = 0.97). With increasing temperature the antimony electrode pH readings increased by 0.03 +/- 0.002 pH degree C(-1). With increasing PO2 the pH reading decreased (-0.73 pH/log PO2 mm Hg, r2 = 0.96). In the dog heart the antimony electrode showed a decrease in myocardial pH with increasing PCO2, and an increase in pH when NaHCO3 was given intravenously. Coronary occlusion resulted in paradoxically higher pH readings with the antimony electrode due to the effect of lowered myocardial PO2 interfering with pH measurement. The dissolution of antimony from the electrode in blood plasma was tested and found to be low. These studies suggest that antimony electrodes have low toxicity and provide accurate pH determinations under conditions of constant PO2. For more widespread clinical application, the problem of oxygen interference needs to be solved.
Adaptive sliding motion tracking control of piezo-driven flexure-based mechanism
Publisher: IEEE
Date: 10-2007
Advance Australasia Fair: A quarter of a century of contributions to cardiothoracic surgical science?
Publisher: Elsevier BV
Date: 04-2016
Stopping vs. continuing aspirin before coronary artery surgery
Publisher: Massachusetts Medical Society
Date: 25-02-2016
Building a sustainable clinical academic workforce to meet the future healthcare needs of A ustralia and N ew Z ealand: report from the first summit meeting
Publisher: Wiley
Date: 09-2015
DOI: 10.1111/IMJ.12854
Abstract: The delivery of healthcare that meets the requirements for quality, safety and cost-effectiveness relies on a well-trained medical workforce, including clinical academics whose career includes a specific commitment to research, education and/or leadership. In 2011, the Medical Deans of Australia and New Zealand published a review on the clinical academic workforce and recommended the development of an integrated training pathway for clinical academics. A bi-national Summit on Clinical Academic Training was recently convened to bring together all relevant stakeholders to determine how best to do this. An important part understood the lessons learnt from the UK experience after 10 years since the introduction of an integrated training pathway. The outcome of the summit was to endorse strongly the recommendations of the medical deans. A steering committee has been established to identify further stakeholders, solicit more information from stakeholder organisations, convene a follow-up summit meeting in late 2015, recruit pilot host institutions and engage the government and future funders.
Retransplantation in heart-lung recipients with obliterative bronchiolitis
Publisher: Elsevier BV
Date: 04-1995
Surgical slave with a novel method for force sensing and trocar friction reduction
Publisher: Trans Tech Publications, Ltd.
Date: 12-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/AMR.622-623.1362
Abstract: Minimally invasive surgery (MIS) has had a major impact on modern day surgery, and has become the standard for various procedures. MIS however suffers from various impediments, and as a result, has seen robotic surgery gain rapid popularity. It is yet to be seen whether robotic surgery will cause another major paradigm shift, as these systems still require large costs, take up too much space, have an unclear cost benefit, and provide little or no force feedback. This paper presents a slave design for MIS, and a brief literature review on design requirements is given. A novel tool design for force/torque sensing is discussed, which uses an overcoat method to reduce measurement corruption at the trocar, and uses a single external 6-DOF f/t sensor.
An Australian risk prediction model for determining early mortality following aortic valve replacement
Publisher: Oxford University Press (OUP)
Date: 06-2011
DOI: 10.1016/J.EJCTS.2011.01.060
Abstract: To develop a multivariable logistic risk model for predicting early mortality following aortic valve replacement (AVR) in adults, and to compare its performance against existing AVR-dedicated models. Prospectively collected data from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) database project were used. Thirty-five preoperative variables from AVR literature were considered for analysis by chi-square method and multiple logistic regression. Using the bootstrap re-s ling technique for variable selection, five plausible models were identified. Based on models' calibration, discrimination and predictive capacity during n-fold validation, a final model, the AVR-Score, was chosen. An additive score, derived from the final model, was also validated externally in a consecutive cohort. The performance of AVR-dedicated risk models from the North West Quality Improvement Program (NWQIP) and the Northern New England Cardiovascular Study (NNE) groups were also assessed using the receiver operating characteristic (ROC) curve and the Hosmer-Lemeshow (H-L) chi-square test. Between July 2001 and June 2008, a total of 3544 AVR procedures were performed. Early mortality was 4.15%. The AVR-Score contained the following predictors: age, New York Heart Association class, left main disease, infective endocarditis, cerebrovascular disease, renal dysfunction, previous cardiac surgery and estimated ejection fraction. Our final model (AVR-Score) obtained an average area under ROC curve of 0.78 (95% confidence interval (CI): 0.76, 0.80) and an H-L p-value of 0.41 (p>0.05) during internal validation, indicating good discrimination and calibration capacity. External validation of the additive score on a consecutive cohort of 1268 procedures produced an ROC of 0.73 (0.62, 0.84) and an H-L p-value of 0.48 (p>0.05). The NWQIP and NNE risk models achieved acceptable discrimination of ROC of 0.77 (0.73, 0.81). However, both models obtained H-L p-values of 0.002 (p<0.05), indicating a poor fit in our cohort. Existing AVR-dedicated risk models were deemed inappropriate for risk prediction in the Australian population. A preoperative risk model was developed using prospective data from a contemporary AVR cohort.
Soft tissue deformation with reaction-diffusion process for surgery simulation
Publisher: Elsevier BV
Date: 02-2012
Understanding noncardiac complications following coronary artery bypass graft surgery
Publisher: OMICS Publishing Group
Date: 03-2014
DOI: 10.2217/CPR.14.1
Giant Aortic Mural Thrombus
Publisher: Hindawi Limited
Date: 05-04-2016
DOI: 10.1111/JOCS.12748
A New Methodology for Deformable Object Simulation
Publisher: IEEE
Date: 2005
Preoperative atrial fibrillation is an independent risk factor for mid-term mortality after concomitant aortic valve replacement and coronary artery bypass graft surgery
Publisher: Oxford University Press (OUP)
Date: 03-01-2013
DOI: 10.1093/ICVTS/IVS538
Bilateral sequential single lung transplantation for pulmonary hypertension and Eisenmenger's syndrome
Publisher: Elsevier BV
Date: 02-2000
DOI: 10.1016/S0003-4975(99)01082-6
Abstract: Lung transplantation, with and without intracardiac repair for pulmonary hypertension (PH) and Eisenmenger's syndrome (EIS), has become an alternative transplant strategy to combined heart and lung transplantation (HLT). Thirty-five patients with PH or EIS underwent either bilateral sequential single lung transplantation (BSSLT, group I, n = 13) or HLT (group II, n = 22). Another 74 patients, who underwent BSSLT for other indications, served as controls (group III). Immediate allograft function, early and medium-term outcomes, lung function, and 2-year survival were compared between the groups. Comparisons between groups I and II showed no significant difference in any variables except percent predicted forced vital capacity. Immediate allograft function was significantly inferior (p < 0.05) and the blood loss was greater (p < 0.01) in group I when compared with those in group III. However, this resulted in no significant difference in early and medium-term outcomes, and 2-year survival between the 2 groups. BSSLT for PH and EIS can be performed as an alternative procedure to HLT without an increase in early and medium-term morbidity and mortality. Results are comparable with BSSLT performed for other indications.
Progress Towards a National Cardiac Procedure Database-Development of the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) and Melbourne Interventional Group (MIG) Registries
Publisher: Elsevier BV
Date: 2011
DOI: 10.1016/J.HLC.2010.10.002
Abstract: Since the call for a National Cardiac Procedures Database in 2001, much work has been accomplished in both cardiac surgery and interventional cardiology in an attempt to establish a unified, systematic approach to data collection, defining a common minimum dataset pertinent to the Australian context, and instituting quality control measures to ensure integrity and privacy of data. In this paper we outline the aims of the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) and the Melbourne Interventional Group (MIG) registries, and propose a comprehensive set of standardised data elements and their definitions to facilitate transparency in data collection, consistency between these and other data sets, and encourage ongoing peer-review. The aims are to improve outcomes for patients by determining key performance indicators and standards of performance for hospital units, to allow estimation of procedural risks and likelihood of outcomes for patients, and to report outcomes to relevant stake-holders and the public.
Development and control of a two DOF linear–angular precision positioning stage
Publisher: Elsevier BV
Date: 12-2015
A propensity-score matched analysis on the impact of postoperative atrial fibrillation on the early and late outcomes after concomitant aortic valve replacement and coronary artery bypass graft surgery
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2014
Bridging to cardiac transplantation with the novacor left ventricular assist system
Publisher: Elsevier BV
Date: 07-1994
Training surgeon status is not associated with an increased risk of early or late mortality after isolated aortic valve replacement surgery
Publisher: VM Media SP. zo.o VM Group SK
Date: 15-04-2014
A Cost-analysis Study of Robotic Versus Conventional Mitral Valve Repair
Publisher: Elsevier BV
Date: 07-2010
DOI: 10.1016/J.HLC.2010.02.009
Abstract: Robotic mitral valve repair has been performed in Australia since 2004. The aim of this study was to perform a cost-analysis of robotic mitral valve repair (MVR) with direct comparison to conventional MVR surgery. All isolated MVRs performed within one metropolitan hospital network, between June 2005 and June 2008, were retrospectively compared. Ad hoc cost analysis was conducted. There were 107 robotic and 40 conventional MVRs performed. The post-operative degrees of mitral regurgitation were comparable. Total operating time was 18% longer in robotic compared to conventional (239 min vs. 202 min, p<0.001, 95% CI: 11-27%). In robotic, Intensive Care Unit stay was reduced by 19% (p=0.002, 37 h vs. 45 h), and length of hospital stay was reduced by 26% (p<0.001, 6.47 days vs. 8.76 days). Mean hospital cost, without including capital costs, was not significantly increased (AUD$18,503 vs. AUD$17,880 p=0.176, 95% CI: -282 to 1,530). Robotic mitral repair can be performed with similar immediate repair success rates as conventional surgery with a shorter recovery time, but a slightly longer operative time. There is no significant increase in cost over conventional surgery.
Impact of socioeconomic status and rurality on early outcomes and mid-term survival after CABG: Insights from a multicentre registry
Publisher: Elsevier BV
Date: 08-2014
DOI: 10.1016/J.HLC.2014.02.008
Abstract: We examined whether socioeconomic status and rurality influenced outcomes after coronary surgery. We identified 14,150 patients undergoing isolated coronary surgery. Socioeconomic and rurality data was obtained from the Australian Bureau of Statistics and linked to patients' postcodes. Outcomes were compared between categories of socioeconomic disadvantage (highest versus lowest quintiles, n= 3150 vs. 2469) and rurality (major cities vs. remote, n=9598 vs. 839). Patients from socioeconomically-disadvantaged areas experienced a greater burden of cardiovascular risk factors including diabetes, obesity and current smoking. Thirty-day mortality (disadvantaged 1.6% vs. advantaged 1.6%, p>0.99) was similar between groups as was late survival (7 years: 83±0.9% vs. 84±1.0%, p=0.79). Those from major cities were less likely to undergo urgent surgery. There was similar 30-day mortality (major cities: 1.6% vs. remote: 1.5%, p=0.89). Patients from major cities experienced improved survival at seven years (84±0.5% vs. 79±2.0%, p=0.010). Propensity-analysis did not show socioeconomic status or rurality to be associated with late outcomes. Patients presenting for coronary artery surgery from different socioeconomic and geographic backgrounds exhibit differences in their clinical profile. Patients from more rural and remote areas appear to experience poorer long-term survival, though this may be partially driven by the population's clinical profile.
Surgeons' attitudes towards and usage of evidence-based medicine in surgical practice: A pilot study
Publisher: Wiley
Date: 27-03-2007
DOI: 10.1111/J.1445-2197.2007.04022.X
Abstract: Within surgery the debate about the place of evidence-based medicine (EBM) has focused on the nature and compatibility of EBM with surgical practice with an inevitable polarization of opinion. However, EBM techniques are being embedded into undergraduate medical curricula and surgical training programs across Australia. The Monash University Department of Surgery at Monash Medical Centre implemented a pilot study to explore current knowledge, attitudes and behaviours of practising surgeons towards EBM techniques. Descriptive survey of surgeons based in a tertiary care environment. The results from the surgeons surveyed suggest that (i) they believe that EBM marginalizes patient involvement in decision-making (ii) they believe that EBM-generated knowledge is useful and is commonly used in daily clinical decision-making--however, not using EBM does not adversely affect their daily clinical decision-making (iii) they have high confidence in their own judgement compared with low confidence in clinical practice guidelines and other sources of evidence and (iv) journal summaries of the latest research related to a subject are the most useful resources in clinical practice above clinical practice guidelines. The importance of incorporating concepts of the 'culture' of surgery as an important factor in understanding and developing new ways to mobilize Australian surgeons to adopt EBM into their practice is discussed.
Acute pulmonary embolectomy
Publisher: Oxford University Press (OUP)
Date: 07-12-2013
DOI: 10.1093/EJCTS/EZS605
Abstract: Acute pulmonary embolism (PE) is a common condition frequently associated with a high mortality worldwide. It can be classified into non-massive, sub-massive and massive, based on the degree of haemodynamic compromise. Surgical pulmonary embolectomy, despite having been in existence for over 100 years, is generally regarded as an option of last resort, with expectedly high mortality rates. Recent advances in diagnosis and recognition of key qualitative predictors of mortality, such as right ventricular stress on echocardiography, have enabled the re-exploration of surgical pulmonary embolectomy for use in patients prior to the development of significant circulatory collapse, with promising results. We aim to review the literature and discuss the indications, perioperative workup and outcomes of surgical pulmonary embolectomy in the management of acute PE.
Excellent short- and long-term outcomes after concomitant aortic valve replacement and coronary artery bypass grafting performed by surgeons in training
Publisher: Elsevier BV
Date: 02-2013
DOI: 10.1016/J.JTCVS.2012.09.073
Abstract: No previous studies have specifically addressed the effect of training on outcomes after concomitant aortic valve replacement and coronary artery bypass grafting. This study evaluated the early and late outcomes after concomitant aortic valve replacement and coronary artery bypass grafting performed by surgeons in training. A retrospective analysis of data collected prospectively by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database between June 2001 and December 2009 was performed. Concomitant aortic valve replacement and coronary artery bypass grafting was performed in 2540 patients of these procedures, 290 (11.4%) were by trainees. Patient demographics, intraoperative characteristics, and early morbidity were compared between trainee and staff cases using chi-square analysis and t tests. Multivariate analyses were used to determine the independent association of training status with 30-day and late mortality. Compared with staff cases, trainee cases were younger (mean age, 73.0 vs 74.2 years P = .025) and less likely to present with triple vessel disease (27.9% vs 38.3%, P = .001) or previous cardiac surgery (6.3% vs 2.8%, P = .016). Trainee cases had longer mean perfusion (160.4 vs 144.6 minutes, P < .001) and crosscl (125.2 vs 114.6 minutes, P < .001) times. The incidence of early complications was similar between the 2 groups. On multivariate analysis, trainee status was not associated with an increased risk of 30-day mortality (2.4% vs 4.0%, P = .348). Moreover, there was no significant difference in long-term outcomes, and 5-year survival was comparable in both groups (79.6% vs 77.4%, P = .200). Concomitant aortic valve replacement and coronary artery bypass grafting can be safely and effectively performed by properly supervised trainees in the contemporary era. It is imperative to offer training opportunities to junior surgeons in this complex procedure to ensure quality patient outcomes in the future.
The prognostic value of elevated neutrophil–lymphocyte ratio for cardiac surgery‐associated acute kidney injury: A systematic review and meta‐analysis
Publisher: Wiley
Date: 25-11-2023
DOI: 10.1111/AAS.14170
Abstract: Patients undergoing cardiac surgery are at significant risk of developing postoperative acute kidney injury (AKI). Neutrophil–lymphocyte ratio (NLR) is a widely available inflammatory biomarker which may be of prognostic value in this setting. We conducted a systematic review and meta‐analysis of studies reporting associations between perioperative NLR with postoperative AKI. We searched Medline, Embase and the Cochrane Library, without language restriction, from inception to May 2022 for relevant studies. We meta‐analysed the reported odds ratios (ORs) with 95% confidence intervals (CIs) for both elevated preoperative and postoperative NLR with risk of postoperative AKI and need for renal replacement therapy (RRT). We conducted a meta‐regression to explore inter‐study statistical heterogeneity. Twelve studies involving 10,724 participants undergoing cardiac surgery were included, with eight studies being deemed at high risk of bias using PROBAST modelling. We found statistically significant associations between elevated preoperative NLR and postoperative AKI (OR 1.45, 95% CI 1.18–1.77), as well as postoperative need for RRT (OR 2.37, 95% CI 1.50–3.72). Postoperative NLR measurements were not of prognostic significance. Elevated preoperative NLR is a reliable inflammatory biomarker for predicting AKI following cardiac surgery.
A simplified method of harvesting and dilating the radial artery achieves acceptable clinical outcomes
Publisher: Wiley
Date: 06-05-2000
DOI: 10.1046/J.1440-1622.2000.01829.X
Abstract: The recent successful revival of the radial artery as a coronary-bypass conduit has been attributed to a minimally traumatic harvesting technique without diathermy, combined with long-term oral calcium antagonist therapy. We describe a simplified technique of harvesting the radial artery, which reduces procurement time and maintains conduit relaxation. Radial arteries were harvested using diathermy and topical glyceryl trinitrate-verapamil dilator solution. Postoperatively, intravenous glyceryl trinitrate, but no calcium antagonist was used. The clinical results in the first 100 consecutive patients receiving radial artery grafts (RA group), procured using this technique, were compared with a group of 100 patients receiving saphenous vein conduits (SV group) immediately prior to the introduction of the radial artery at our institution. There were no demographic differences between the two groups, other than the SV group being slightly older. There was one intraoperative death in each group. There was no difference in the rate of peri-operative myocardial infarction or length of stay in the intensive care unit. At a median follow-up time of 16 months for the RA group, and 25 months for the SV group, the survival rates were 97 and 94%, respectively. All survivors were in the New York Heart Association class I. In the SV group, two postoperative angioplasties were performed. These early results suggest that this method of procuring the radial artery using diathermy, glyceryl trinitrate and no postoperative calcium antagonists, is rapid, safe and effective. The continued use of this technique is justified, while awaiting the results of long-term angiographic studies.
Epicardial High-intensity Focused Ultrasound Cardiac Ablation for Surgical Treatment of Atrial Fibrillation
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1016/J.HLC.2008.08.003
Abstract: The available alternatives to an effective but technically complex Cox maze procedure for surgical treatment of atrial fibrillation include ablation using radiofrequency, microwave, laser, cryotherapy or ultrasound energy sources. The purpose of this study was to evaluate the safety and efficacy profile of high-intensity focused ultrasound cardiac ablation for the surgical treatment of atrial fibrillation. 14 patients underwent epicardial high-intensity focused ultrasound treatment for atrial fibrillation using the Epicor cardiac ablation system between August 2006 and August 2007. The procedure was performed on the beating heart prior to the commencement of cardiopulmonary bypass for concomitant cardiac procedures. Physical examination, electrocardiography and 24-h Holter monitoring were used to determine the postoperative heart rhythm. There were no deaths directly related to the procedure. One patient with myelodysplastic syndrome died of septic complications. Three patients required cardioversion at 1 day, 3- and 4-month intervals postoperatively. The mean follow-up period was 9 months. Currently 10/13 (77%) patients are in sinus rhythm, one patient required insertion of a permanent pacemaker, one patient is in atrial fibrillation and another patient is in atrial flutter. Epicardial high-intensity focused ultrasound ablation is a viable alternative to the Cox maze procedure for the surgical treatment of atrial fibrillation. It is a safe and efficient procedure that does not require cardiopulmonary bypass and may potentially be performed using less invasive surgical techniques.
Robust motion tracking control of piezo-driven flexure-based four-bar mechanism for micro/nano manipulation
Publisher: Elsevier BV
Date: 03-2008
Will tissue engineering become the 21st century's answer to cardiovascular disease?
Publisher: Elsevier BV
Date: 2002
Graduate programs in surgical education: celebrating the first decade
Publisher: Wiley
Date: 12-11-2022
DOI: 10.1111/ANS.18159
Non-operative management of tube thoracostomy induced pulmonary artery injury
Publisher: Oxford University Press (OUP)
Date: 10-2009
DOI: 10.1510/ICVTS.2009.209262
Abstract: Tube thoracostomy insertion is a common procedure in the management of air and fluid collections in the pleural space. Pulmonary artery injury is a rare but serious complication following intercostal catheterisation. This complication is usually managed surgically. We report a case of successful non-operative management of a pulmonary artery injury after tube thoracostomy.
Critical analysis of early and late outcomes after isolated coronary artery bypass surgery in elderly patients
Publisher: Elsevier BV
Date: 11-2011
DOI: 10.1016/J.ATHORACSUR.2011.05.086
Abstract: The proportion of elderly (≥80 years) patients undergoing coronary artery bypass surgery (CABG) is increasing. A retrospective analysis of data, collected by the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Program between June 2001 and December 2009 was performed. Isolated CABG was performed in 21,534 patients of these, 1,664 (7.7%) were at least 80 years old (group 1). Patient characteristics, morbidity, and short-term mortality of these patients were compared with those aged less than 80 years (group 2). The long-term outcome of group 1 patients after CABG surgery was compared with an age and sex-matched Australian population. Patients over 80 years old were more likely to be female (36.6% vs 17.3%, p < 0.001) and presented significantly more often with heart failure, hypertension, and triple-vessel disease (all p < 0.05). The 30-day mortality was higher in group 1 patients (4.2% vs 1.5%, p 24 hours) ventilation (14.2% vs 8.2%, p < 0.001), renal failure (7.3% vs 3.4%, p < 0.001), and mean intensive care unit stay (60.7 vs 42.5 hours, p < 0.001). The 5-year survival of elderly patients (73%) was comparable with the age-matched Australian population. Independent risk factors for 30-day mortality in group 1 patients included preoperative renal failure (p = 0.010), congestive heart failure (p = 0.014), and a nonelective procedure (p = 0.016). Elderly patients who undergo isolated CABG have significantly lower perioperative risks than have been previously reported. The long-term survival of these patients is comparable with an age-adjusted population.
An electromechanical based deformable model for soft tissue simulation
Publisher: Elsevier BV
Date: 11-2009
DOI: 10.1016/J.ARTMED.2009.08.003
Abstract: Soft tissue deformation is of great importance to surgery simulation. Although a significant amount of research efforts have been dedicated to simulating the behaviours of soft tissues, modelling of soft tissue deformation is still a challenging problem. This paper presents a new deformable model for simulation of soft tissue deformation from the electromechanical viewpoint of soft tissues. Soft tissue deformation is formulated as a reaction-diffusion process coupled with a mechanical load. The mechanical load applied to a soft tissue to cause a deformation is incorporated into the reaction-diffusion system, and consequently distributed among mass points of the soft tissue. Reaction-diffusion of mechanical load and non-rigid mechanics of motion are combined to govern the simulation dynamics of soft tissue deformation. An improved reaction-diffusion model is developed to describe the distribution of the mechanical load in soft tissues. A three-layer artificial cellular neural network is constructed to solve the reaction-diffusion model for real-time simulation of soft tissue deformation. A gradient based method is established to derive internal forces from the distribution of the mechanical load. Integration with a haptic device has also been achieved to simulate soft tissue deformation with haptic feedback. The proposed methodology does not only predict the typical behaviours of living tissues, but it also accepts both local and large-range deformations. It also accommodates isotropic, anisotropic and inhomogeneous deformations by simple modification of diffusion coefficients.
Thermal-mechanical-based soft tissue deformation for surgery simulation
Publisher: Informa UK Limited
Date: 2010
Current medical students' understanding of Surgical Education and Training
Publisher: Wiley
Date: 15-12-2012
DOI: 10.1111/J.1445-2197.2011.05944.X
Abstract: Background: The current Surgical Education and Training (SET) programme in Australia and New Zealand has been implemented to streamline surgical training. As applications to the SET programme can occur as early as the 2nd post‐graduate year, early preparation is vital to ensure a successful outcome in gaining a SET position. We wish to demonstrate to what degree medical students are aware of the SET structure and application requirements to determine if further assistance to future SET candidates is required. Methods: A standardized questionnaire was delivered to students of an Australian Medical School via an online medium. Ethics approval was granted, and all surveys were completed anonymously and voluntarily. One hundred eighty‐two completed surveys were received. Results: Eighteen percent of surveyed participants felt they had a good understanding of the SET programme, with 82% stating they had minimal or no understanding of the programme. Fourteen percent felt they had the information needed to pursue a career in surgery. Fifty‐three percent were unaware that the College outlined areas of core competencies required in their training, with 75% unable to name any core competencies. Conclusion: There are a large proportion of medical students potentially considering a career in surgery. However, only a small number feel that they have been adequately equipped throughout their medical course to understand the steps needed to build a strong application for SET.
Impact of left ventricular dysfunction on early and late outcomes in patients undergoing concomitant aortic valve replacement and coronary artery bypass graft surgery
Publisher: VM Media SP. zo.o VM Group SK
Date: 26-07-2013
DOI: 10.5603/CJ.2013.0102
Angiosarcoma of the colon - Report of a case with long-term survival
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-1990
DOI: 10.1007/BF02055479
Guidelines for the establishment of an adult cardiac surgery unit (CSU)
Publisher: Elsevier BV
Date: 09-2013
Feasibility Study of Robust Neural Network Motion Tracking Control of Piezoelectric Actuation Systems for Micro/Nano Manipulation
Publisher: Springer Berlin Heidelberg
Date: 2008
Comparative review of large animal models for suitability of proximal aortic endovascular repair
Publisher: University Library System, University of Pittsburgh
Date: 07-03-2022
Abstract: Background The advent of TEVAR heralds a paradigm shift in treating descending aortopathies and is viewed as a potential option for ascending aortic dissection (AD) repair too. Currently, TEVAR’s usage for ascending aortopathies remains limited. Consequently, an urgent requirement exists to choose appropriate animal models to better contemporary understanding of endovascularly treating Type-A ADs. This review article provides a summary of current literature on this topic. Two broad sections are covered, including the macroscopic differences between adult swine, ovine and porcine species versus that of their human counterparts, as well as the valvular, aortic and coronary vasculature variances. Methods A narrative review was conducted to integrate current findings of anatomical differences in valvular and ascending aortic anatomy amongst the aforementioned species. An electronic search of PubMed and Ovid Medline databases from January 1965 to June 2020 was performed, limited to articles published in English. Results Whilst macroscopic anatomy remains grossly similar, differences in valvular leaflet shape are present, with swine and porcine models possessing anatomic characteristics that are comparable to their human counterparts. Research into inter-species ascending aortic anatomy has not been extensively performed, highlighting a literature gap. Conversely, multiple morphological studies have highlighted that swine coronary vasculature is closely resemblant to that of man. Conclusion Both swine and ovine species are suitable as appropriate animal models in examining the feasibility of endovascular stent-grafts for ascending ADs. However, given the similarities in coronary and aortic valve anatomy to their human analogues, porcine models are better suited for this purpose.
A vision-based measurement algorithm for micro/nano manipulation
Publisher: IEEE
Date: 07-2013
Modelling a precision loadcell using neural networks for vision-based force measurement in cell micromanipulation
Publisher: IEEE
Date: 07-2013
Minimally invasive mitral valve replacement: Port-access technique, feasibility, and myocardial functional preservation
Publisher: Elsevier BV
Date: 06-1997
DOI: 10.1016/S0022-5223(97)70287-3
Abstract: Interleukin 32 (IL-32) is a recently described pro-inflammatory cytokine implicated in chronic hepatitis C virus (HCV)-related inflammation and fibrosis. IL-32α is the most abundant IL-32 isoform. Circulating IL-32α levels were documented in patients with chronic HCV infections ( Circulating IL-32α levels in patients with chronic HCV were similar to those of spontaneously resolved and HCV-naive controls. HCV protein induced IL-32α responses were similar in chronic HCV patients and HCV-naive controls. In patients with chronic HCV, serum IL-32α levels correlated with worsening METAVIR fibrosis (F) scores from F0 to F3 ( IL-32α activity is associated with worsening fibrosis scores in non-cirrhotic, chronic HCV patients.
Alkaptonuria-associated aortic stenosis
Publisher: Hindawi Limited
Date: 07-2013
DOI: 10.1111/JOCS.12129
Abstract: Alkaptonuria is an autosomal recessive disorder of tyrosine metabolism, which results in accumulation of unmetabolized homogentisic acid and its oxidized product in various tissues, including the heart. Cardiovascular involvement is a rare but serious complication of the disease. We present two patients who have undergone successful aortic valve replacement for alkaptonuria-associated aortic stenosis along with a review of the literature.
Can anatomy teaching make a come back?
Publisher: Wiley
Date: 03-2005
Microstructure, thermal properties and crystallinity of amadumbe starch nanocrystals
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.IJBIOMAC.2017.04.030
Abstract: Amadumbe (Colocasia esculenta), commonly known as taro is a tropical tuber that produces starch-rich underground corms. In this study, the physicochemical properties of starch nanocrystals (SNC) prepared by acid hydrolysis of amadumbe starches were investigated. Two varieties of amadumbe corms were used for starch extraction. Amadumbe starches produced substantially high yield (25%) of SNC's. These nanocrystals appeared as aggregated and in idual particles and possessed square-like platelet morphology with size: 50-100nm. FTIR revealed high peak intensities corresponding to OH stretch, CH stretch and H
Does the addition of a radial artery graft improve survival after higher risk coronary artery bypass grafting? A propensity-score analysis of a multicentre database
Publisher: Oxford University Press (OUP)
Date: 18-03-2013
DOI: 10.1093/EJCTS/EZT116
Abstract: The use of the radial artery as a second arterial graft during coronary surgery has grown in popularity due to high patency and low harvest site complication rates. We sought to assess whether higher risk patients derive prognostic benefit. From 2001 to 2009, 11,388 patients underwent isolated primary multivessel coronary surgery. We identified a higher risk subgroup (n = 2581) according to emergent status, coronary instability, low ejection fraction and/or aortic counterpulsation. Among these, 1832 (71%) received at least one radial artery graft in addition to a left internal thoracic artery (LITA). The remaining 749 (29%) received LITA and veins only. Patients not receiving a radial artery were more likely to be elderly, female, have poor left ventricular function or be of emergent status. These patients experienced higher unadjusted 30-day mortality (radial: 2% vs vein: 8%, P < 0.0001) with lower unadjusted 7-year survival (80 ± 1.3 vs 67 ± 2.4%, P 0.99), stroke (1 vs 1%, P > 0.99), myocardial infarction (1 vs 2%, P = 0.79), and any morbidity/mortality (34 vs 35%, P = 0.95). At 7 years, survival rates between the radial and vein groups were similar (radial: 75 ± 2.6% vs vein: 74 ± 2.9%, P = 0.65). Patients with the greatest coronary instability, urgency of surgery or impairment of ventricular function are not disadvantaged in early outcomes or mid-term survival by the use of only a single arterial graft.
Surgery is not just an art [7]
Publisher: Wiley
Date: 12-2006
Stanford Type A Aortic Dissection in Pregnancy: A Diagnostic and Management Challenge
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.HLC.2012.08.005
Abstract: In women under the age of 40, over 50% of type A aortic dissections occur in the obstetric population. This is a complex situation, with potential catastrophic outcomes for mother and child. Time to diagnosis is often delayed by a low degree of suspicion, atypical presentation and difficulties investigating pregnant women. Management requires early involvement of multiple teams and appreciation of potential complications. We report our experience (the largest series described) and describe our surgical strategy. A retrospective search of the cardiothoracic surgical database at our centre from 2002 to 2010 identified five pregnant women with type A dissections. Median time to diagnosis was 18.5 h (range 5.5-150 h) and median time from diagnosis to arrival in the operating theatre was 1.5 h (range 0.5-54 h). Four patients underwent concomitant Caesarean section and dissection repair. There was one maternal death and one unrelated foetal death. Occurrence of type A aortic dissection in pregnant women is uncommon but potentially catastrophic. A high index of suspicion and timely investigations are necessary to expedite definitive management. Sound surgical strategies and collaboration with appropriate teams are necessary to optimise outcome.
Pose estimation with capacitive sensors experiencing non-linear response to tilt
Publisher: IEEE
Date: 07-2014
Development of clinicalquality registries in australia: The way forward
Publisher: AMPCo
Date: 09-2011
DOI: 10.5694/MJA11.10779
Initial twelve months experience and analysis for 2001-2002 from the Australasian Society of Cardiac and Thoracic Surgeons - Victorian database project
Publisher: Elsevier BV
Date: 09-2004
DOI: 10.1016/J.HLC.2004.05.006
Abstract: The Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) have established a database for the collection and analysis of the results of cardiac surgery in Australia and New Zealand. Initially data has been collected only in Victoria public hospitals. This report covers the first 12 months of data collection from 1st August 2001 to 1st July 2002. Whilst cardiac surgical performance in Australia is considered to be of a high standard equivalent to other developed countries, there is currently no systematic approach to data collection in order to provide performance indicators and benchmarks. The development of an Australasian cardiac surgical database and performance indicators will enable benchmarking and comparison with international standards which should lead to performance improvements. A database definition set and standardised data collection form was developed by the ASCTS for all participating cardiac surgery units in public hospitals in Victoria. Opt-off consent for subject inclusion in the database was approved by each participating institutional ethics review committee. An electronic database and reporting application was developed. Data included in this analysis is from the initial 12 months collection from all hospitals participating in the project from 1st August 2001 to 31st July 2002. Overall, there were 2982 procedures performed in this period of which 2969 had sufficient data to be included in this analysis (99.5%). The majority of procedures 2017 (68%) being undertaken were isolated coronary artery bypass surgery (CABG). The mean age of all subjects undergoing procedures was 65 years (range: 18-91 years) and 70% were male. 64% of all procedures were elective and 6.1% emergency or salvage. Median post-procedure length of hospital stay for all procedures was 6.0 days and intensive care unit (ICU) stay was 23.0h. Re-operation for haemorrhage occurred in 2.1% of all cases and deep sternal infection in 0.4% of all cases. Crude 30-day operative mortality was 3.6% for all procedures 2.1% for isolated CABG, 3.6% for valve procedures, 5.2% for valve and CABG and 11.4% for other cardiac surgical procedures. Mortality rates increased from 1.8% for elective procedures to 4.1% for urgent and 24.6% for emergency or salvage operations. In comparison to international figures from the USA and UK, mortality rates following isolated CABG were lower whilst average length of hospital stay post-procedure was higher. The ASCTS database project is now well established and the electronic database and reporting module is in operation in all participating sites. The risk-adjusted isolated operative mortality suggests cardiac surgical performance in Victoria compares well with international standards. As the database develops, local risk-adjustment models for mortality and morbidity for each procedure will be developed to enable appropriate between hospital comparisons.
Soft tissue modelling through autowaves for surgery simulation
Publisher: Springer Science and Business Media LLC
Date: 04-08-2006
DOI: 10.1007/S11517-006-0084-7
Abstract: Modelling of soft tissue deformation is of great importance to virtual reality based surgery simulation. This paper presents a new methodology for simulation of soft tissue deformation by drawing an analogy between autowaves and soft tissue deformation. The potential energy stored in a soft tissue as a result of a deformation caused by an external force is propagated among mass points of the soft tissue by non-linear autowaves. The novelty of the methodology is that (i) autowave techniques are established to describe the potential energy distribution of a deformation for extrapolating internal forces, and (ii) non-linear materials are modelled with non-linear autowaves other than geometric non-linearity. Integration with a haptic device has been achieved to simulate soft tissue deformation with force feedback. The proposed methodology not only deals with large-range deformations, but also accommodates isotropic, anisotropic and inhomogeneous materials by simply changing diffusion coefficients.
Interprofessional non-technical skills for surgeons in disaster response: A qualitative study of the Australian perspective
Publisher: Informa UK Limited
Date: 25-07-2013
DOI: 10.3109/13561820.2012.706337
Abstract: Interprofessional non-technical skills for surgeons in disaster response have not yet been developed. The aims of this study were to identify the non-technical skills required of surgeons in disaster response and training for disaster response and to explore the barriers and facilitators to interprofessional practice in surgical teams responding to disasters. Twenty health professionals, with prior experience in natural disaster response or education, participated in semi-structured in-depth interviews. A qualitative matrix analysis design was used to thematically analyze the data. Non-technical skills for surgeons in disaster response identified in this study included skills for austere environments, cognitive strategies and interprofessional skills. Skills for austere environments were physical self-care including survival skills, psychological self-care, flexibility, adaptability, innovation and improvisation. Cognitive strategies identified in this study were "big picture" thinking, situational awareness, critical thinking, problem solving and creativity. Interprofessional attributes include communication, team-player, sense of humor, cultural competency and conflict resolution skills. "Interprofessionalism" in disaster teams also emerged as a key factor in this study and incorporated elements of effective teamwork, clear leadership, role adjustment and conflict resolution. The majority of participants held the belief that surgeons needed training in non-technical skills in order to achieve best practice in disaster response. Surgeons considerring becoming involved in disaster management should be trained in these skills, and these skills should be incorporated into disaster preparation courses with an interprofessional focus.
Perspectives on the Impact on Vocal Function of Heavy Vocal Load Among Working Professional Music Theater Performers
Publisher: Elsevier BV
Date: 05-2013
DOI: 10.1016/J.JVOICE.2012.12.003
Abstract: Music theater singers (MTS) typically have a heavy vocal load, but the impact on their voices has not been previously evaluated. A group of 49 MTS from two professional productions were administered the Singing Voice Handicap Index (SVHI). Responses for the SVHI demonstrated that, although the SVHI supported the performers' self-report of healthy vocal status, it lacked the sensitivity to detect potential subtle fluctuations or changes in physical functioning of the voice for working singers. Secondarily, descriptive data regarding professional working singers' perspectives were collected regarding how their singing voices typically responded to performing in a music theater production after a show, across a working week, and across a production season. Seventy-nine currently performing MTS were involved in a series of focus group interviews (n=43) or a written survey (n=36) to detail their perception of the impact of performing in an eight-show per week professional production on their vocal function and vocal health. Thematic analysis revealed the MTS commonly perceived transient and variable changes in their singing voice status in both positive and negative directions after heavy vocal load. Based on these data, a list of 97 descriptors of these perceptual changes was generated using the singers' own terminology and experiences. These included symptoms of vocal impairment and vocal fatigue but also some novel descriptors of positive vocal changes to the physical functioning of the singing voice as a perceived consequence of heavy vocal load. This study offers new and valuable insights into performers' perceptions of the impact of performing in a musical theater production on physical aspects of vocal function.
An improved approach to estimate soft tissue parameters using genetic algorithm for minimally invasive measurement
Publisher: IEEE
Date: 2009
Urinary oxygen tension: A clinical window on the health of the renal medulla?
Publisher: American Physiological Society
Date: 2014
DOI: 10.1152/AJPREGU.00437.2013
Abstract: We describe the determinants of urinary oxygen tension (Po 2 ) and the potential for use of urinary Po 2 as a “physiological biomarker” of the risk of acute kidney injury (AKI) in hospital settings. We also identify knowledge gaps required for clinical translation of bedside monitoring of urinary Po 2 . Hypoxia in the renal medulla is a hallmark of AKI of erse etiology. Urine in the collecting ducts would be expected to equilibrate with the tissue Po 2 of the inner medulla. Accordingly, the Po 2 of urine in the renal pelvis changes in response to stimuli that would be expected to alter oxygenation of the renal medulla. Oxygen exchange across the walls of the ureter and bladder will confound measurement of the Po 2 of bladder urine. Nevertheless, the Po 2 of bladder urine also changes in response to stimuli that would be expected to alter renal medullary oxygenation. If confounding influences can be understood, urinary bladder Po 2 may provide prognostically useful information, including for prediction of AKI after cardiopulmonary bypass surgery. To translate bedside monitoring of urinary Po 2 into the clinical setting, we require 1) a more detailed knowledge of the relationship between renal medullary oxygenation and the Po 2 of pelvic urine under physiological and pathophysiological conditions 2) a quantitative understanding of the impact of oxygen transport across the ureteric epithelium on urinary Po 2 measured from the bladder and 3) a simple, robust medical device that can be introduced into the bladder via a standard catheter to provide reliable and continuous measurement of urinary Po 2 .
Clinical Outcomes in Surgical and Transcatheter Aortic Valve Replacement: An ANZSCTS Database Review 2001-2019
Publisher: Elsevier BV
Date: 08-2022
DOI: 10.1016/J.HLC.2022.04.047
Abstract: Since the last formal publication reporting on the findings of the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) database on surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) in 2016, transcatheter approaches have become common practice. There has been an increase in use of TAVR following large, randomised control trials that only report on short-term outcomes in a selective cohort. This study aims to report on primary outcome measures and identify complications associated with SAVR and TAVR from a large national database. From the ANZSCTS database (2001-19), 14,097 SAVR and 1,194 TAVR patients were identified with clinical details and 30-day follow-up available. The primary endpoint was the composite of all-cause mortality and/or permanent stroke at 30 days. Secondary endpoints were post-procedure complications requiring treatment. Logistical regression followed by propensity score matching was performed. Using logistical regression when all patient factors considered for all patients who had SAVR and TAVR, the only preoperative factors that had an impact on 30-day mortality was cerebrovascular disease, respiratory disease, preoperative dialysis, angina, and hypertension. Primary outcome 30-day mortality rate was 1.83% in the SAVR group, and 1.68% in patients in the TAVR group, p=0.7001, and permanent stroke was seen in 1.07% patients in the SAVR group, and 1.26% patients in the TAVR group. Acute limb ischaemia, aortic dissection, ventricular tachycardia, bradyarrhythmia and heart block were more common following TAVR (p<0.001), while reintubation and atrial arrhythmia were more common following SAVR (p<0.001). In the real world SAVR and TAVR have been used in very different patient groups and it is difficult to compare as different baseline characteristics and complications. The two patient groups maintain similarities in primary and secondary endpoints, but differences in life threatening and life altering morbidity remains significant. Collection of SAVR and TAVR data in a combined database may help to better capture and compare these complications and institute strategies to prevent them.
Principles and Practice of Cardiac Surgery
Publisher: Wiley
Date: 2008
Critical evaluation: Is lung volume reduction surgery a forgotten operation?
Publisher: Wiley
Date: 21-08-2008
Common Topics in Thoracic Surgery
Publisher: Wiley
Date: 2008
The Prognostic Significance of Red Cell Distribution Width in Cardiac Surgery: A Systematic Review and Meta-Analysis
Publisher: Elsevier BV
Date: 03-2022
Lung volume reduction surgery in emphysema: A systematic review
Publisher: Elsevier BV
Date: 08-2001
DOI: 10.1016/S0003-4975(01)02421-3
Abstract: The aim of this study was to systematically review the literature regarding the safety and efficacy of lung volume reduction surgery (LVRS) in patients with emphysema. Studies on LVRS to August 2000 were identified using MEDLINE, Embase, Current Contents, and the Cochrane Library. Human studies of patients with upper, lower or diffuse distributions of emphysema were included. All types of bullous emphysema were excluded. A surgeon and researcher independently assessed the retrieved articles for their inclusion in the review. When LVRS was compared with medical management, at 2 years LVRS was associated with a higher FEV1 and at least equivalent survival. The use of staple excision of selected areas of lung appeared to be more efficacious than laser ablation. There is insufficient evidence to show preference for median sternotomy or videoscopically assisted thoracotomy, as the more safe and efficacious procedure. In highly selected patients with emphysema LVRS is deemed an acceptable treatment. To fully evaluate the safety and efficacy of LVRS, outcomes beyond 2 years must be included. The results of prospective randomized trials between medical management and LVRS, now in progress, are essential before a final assessment can be made.
Antifibrinolytics in cardiac surgical patients receiving aspirin: A systematic review and meta-analysis
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1093/BJA/AEN377
Abstract: While conventional practice is to discontinue aspirin prior to elective cardiac surgery there is evidence that its continuation may be associated with improved perioperative outcomes. However, uncertainty exists regarding the efficacy of antifibrinolytic agents in the presence of aspirin. We performed a systematic review and meta-analysis of the literature to address the question of the effects of antifibrinolytic agents in cardiac surgery patients maintained on aspirin in terms of both efficacy and adverse events. We conducted an extensive search for randomized controlled trials of antifibrinolytic use in adult patients undergoing coronary artery bypass grafting +/- valve surgery, where aspirin therapy was maintained or initiated through the preoperative period. Data from 17 trials (n=1620) confirmed the efficacy of antifibrinolytic therapy to reduce both chest-tube drainage (weighted mean difference 374 ml, 95% CI 275-473 ml P<0.00001) and blood transfusion requirements (odds ratio 0.37, 95% CI 0.27-0.49 P<0.00001) in cardiac surgical patients receiving aspirin. We found no difference in the rates of adverse events between groups but observed a trend towards a reduced risk for the composite outcome of thrombotic complications (odds ratio 0.49, 95% CI 0.21-1.13 P=0.09). Antifibrinolytic agents are effective for reducing both chest-tube drainage and transfusion requirements in cardiac surgical patients receiving aspirin. We found no difference between antifibrinolytic and placebo in terms of adverse events but the population was predominantly low-risk. Further studies are required to determine the optimal balance between antiplatelet and antifibrinolytic effects in cardiac surgery.
Paying attention to cardiac surgical risk: An interpretable machine learning approach using an uncertainty-aware attentive neural network
Publisher: Public Library of Science (PLoS)
Date: 30-08-2023
DOI: 10.1371/JOURNAL.PONE.0289930
Abstract: Machine learning (ML) is increasingly applied to predict adverse postoperative outcomes in cardiac surgery. Commonly used ML models fail to translate to clinical practice due to absent model explainability, limited uncertainty quantification, and no flexibility to missing data. We aimed to develop and benchmark a novel ML approach, the uncertainty-aware attention network (UAN), to overcome these common limitations. Two Bayesian uncertainty quantification methods were tested, generalized variational inference (GVI) or a posterior network (PN). The UAN models were compared with an ensemble of XGBoost models and a Bayesian logistic regression model (LR) with imputation. The derivation datasets consisted of 153,932 surgery events from the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) Cardiac Surgery Database. An external validation consisted of 7343 surgery events which were extracted from the Medical Information Mart for Intensive Care (MIMIC) III critical care dataset. The highest performing model on the external validation dataset was a UAN-GVI with an area under the receiver operating characteristic curve (AUC) of 0.78 (0.01). Model performance improved on high confidence s les with an AUC of 0.81 (0.01). Confidence calibration for aleatoric uncertainty was excellent for all models. Calibration for epistemic uncertainty was more variable, with an ensemble of XGBoost models performing the best with an AUC of 0.84 (0.08). Epistemic uncertainty was improved using the PN approach, compared to GVI. UAN is able to use an interpretable and flexible deep learning approach to provide estimates of model uncertainty alongside state-of-the-art predictions. The model has been made freely available as an easy-to-use web application demonstrating that by designing uncertainty-aware models with innately explainable predictions deep learning may become more suitable for routine clinical use.
Chronic extra-aortic balloon counterpulsation: First-in-human pilot study in end-stage heart failure
Publisher: Elsevier BV
Date: 12-2010
DOI: 10.1016/J.HEALUN.2010.06.014
Abstract: Some patients continue to have significant heart failure symptoms despite optimal medical therapy. We describe a first-in-human experience with an implantable non-blood-contacting extra-ascending aortic counterpulsation heart assist system (C-Pulse) in 5 end-stage heart failure patients, aged 54 to 73 years. All patients improved by 1 NYHA class and improvements in invasive hemodynamics were documented in 3 patients. Three of 5 patients (60%) had infectious complications. Two patients were explanted at 5 and 7 weeks, respectively, as a result of mediastinal infection related to the implant procedure. One patient was successfully transplanted at 1 month and 1 remained hemodynamically improved on the device at 6 months but suffered infective complications. The device and protocol have been modified as a result of this pilot study with a further multicenter safety study underway. Although feasibility of this device is suggested by this pilot study, safety and efficacy will need to be examined in a larger cohort with longer follow-up.
Neoaortic root dilatation with saccular aneurysm formation after the arterial switch operation for Taussig-Bing anomaly
Publisher: Elsevier BV
Date: 02-2007
Evidence‐based medicine training and implementation in surgery: the role of surgical cultures
Publisher: Wiley
Date: 27-07-2011
DOI: 10.1111/J.1365-2753.2010.01526.X
Abstract: This qualitative study identifies cultural factors that influence the effective implementation of evidence-based medicine (EBM) in surgical practice among Australian surgeons. In-depth interviews (n = 22) were conducted with surgeons from a variety of specialties within a large hospital system in Victoria, Australia. The interviews explored the surgeons' understanding of EBM and challenges to the adoption of EBM. The canons and procedures of the Miles and Huberman's Matrix Analyses approach to qualitative research guided the coding and organization of the data derived from the semi-structured interviews. Surgeons had a good understanding of EBM, but viewed it as little more than a system of evidence, which was often orced from actual clinical practice. The data also suggested that surgical culture(s) and typologies of surgical style were important variables in the implementation of EBM. The results suggest that the ideal method of EBM implementation is workplace instruction led by surgeons, who exhibit scientist and/or clinician styles of surgical practice EBM training should occur early in the surgeons' careers and EBM practice should be role modelled in the presence of trainees by surgeons who exhibit either a scientist and/or clinician style of surgical practice. The study findings suggest that using pre-existing surgical culture(s) and styles is an important component in the implementation of EBM in surgery. The effective use of the scientist and/or clinician surgeon within the apprenticeship model and the context-specific collegial networks of the surgical profession appear to be key elements in ensuring the successful implementation of EBM in surgery.
The Outcome of Cardiac Surgery in Dialysis-Dependent Patients
Publisher: Elsevier BV
Date: 09-2005
DOI: 10.1016/J.HLC.2005.02.006
Abstract: Patients on dialysis for end-stage renal failure (ESRF) are undergoing cardiac surgery with increasing frequency. Furthermore, ESRF is known to be an important risk factor for complications of cardiac operations performed with cardiopulmonary bypass. To evaluate the outcome of dialysis-dependent patients undergoing cardiac surgery at one institution. A retrospective analysis was performed on consecutive patients with ESRF dependent upon maintenance haemodialysis or peritoneal dialysis who underwent cardiac surgery from January 1998 to August 2002. Thirty-eight patients on dialysis underwent cardiac surgery during this time period (1.5% of total cases). The most common cause for ESRF was diabetic nephropathy (n = 12). Operations performed included isolated coronary artery bypass grafting (CABG, n = 22), CABG and valve surgery (n = 8), and valve surgery alone (n = 6). When allowing for age, sex, surgeon and operative category, the odds ratio for mortality risk of dialysis patients, compared with all others, was 4.9 (95% confidence interval (CI): 1.7-13.9, p = 0.003), and for morbidity risk, was 2.8 (95% CI: 1.4-5.4, p = 0.003). Patients on dialysis have an increased morbidity and mortality following cardiac surgery, however we believe ESRF should not be regarded as an absolute contraindication to cardiac surgery or cardiopulmonary bypass.
Cardiac transplantation: a review
Publisher: SAGE Publications
Date: 02-1995
DOI: 10.1016/0967-2109(95)92894-N
Abstract: Cardiac transplantation is currently a highly successful treatment for selected patients with end-stage cardiac failure. The long-term results are limited by the development of coronary artery vasculopathy, infection and malignancy. The activity of transplantation programmes worldwide is severely limited by the availability of donor organs. Further refinements of immunosuppressive agents are likely to result in improved prevention of both acute and chronic rejection. The donor pool is unlikely to be significantly extended as a result of measures to increase donor organ supply. Alternative methods to allograft transplantation need further investigation to increase the number of therapeutic options available for those patients with end-stage heart failure.
Effects on Cognition of Conventional and Robotically Assisted Cardiac Valve Operation
Publisher: Elsevier BV
Date: 2014
DOI: 10.1016/J.ATHORACSUR.2013.07.018
Abstract: The effect of valve surgical procedures on cognition was investigated in patients undergoing conventional or robotically assisted techniques. The confounding factors of surgical procedure, mood state, preexisting cognitive impairment, and repeated experience with cognitive tests were controlled for. Patients undergoing conventional valve procedures (n = 15), robotically assisted valve procedures (n = 15), and thoracic surgical procedures (n = 15), along with a nonsurgical control group (n = 15) were tested preoperatively, 1 week after operation, and 8 weeks after operation by use of a battery of cognitive tests and a mood state assessment. Surgical group data were normalized against data from the nonsurgical control group before statistical analysis. Patients undergoing conventional valve procedures performed worse than those undergoing robotically assisted valve procedures on every subtest before operation, and this disadvantage persisted after operation. Age and premorbid intelligence quotient were significantly associated with performance on several cognitive subtests. Anxiety, depression, and stress were not associated with impaired cognitive performance in the surgical groups after operation. A week after operation, patients undergoing conventional valve procedures performed worse on the cognitive tests that had a motor component, which may reflect discomfort caused by the sternotomy. Patients undergoing robotically assisted valve procedures were significantly less impaired on information processing tasks 1 week after operation when compared with those undergoing conventional valve procedures. The majority of patients who were impaired 1 week after operation recovered to preoperation levels within 8 weeks. The robotically assisted valve surgical procedure results in more rapid recovery of performance on cognitive tests. However, regardless of the type of surgical intervention, the prospect of a recovery of cognitive performance to preoperative levels is high.
Usefulness of postoperative atrial fibrillation as an independent predictor for worse early and late outcomes after isolated coronary artery bypass grafting (multicenter australian study of 19,497 patients)
Publisher: Elsevier BV
Date: 2012
DOI: 10.1016/J.AMJCARD.2011.08.033
Abstract: Several studies have shown that postoperative atrial fibrillation (POAF) is associated with poorer short- and long-term outcomes after isolated coronary artery bypass grafting surgery. Nevertheless, there is considerable debate as to whether this reflects an independent association of POAF with poorer outcomes or confounding by other factors. We sought to investigate this issue. Data obtained from June 2001 through December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database Program were retrospectively analyzed. Demographic and operative data were compared between patients who developed POAF and those who did not using chi-square and t tests. The independent impact of POAF on 14 short-term complications and long-term mortality was determined using binary logistic and Cox regression, respectively. Excluding patients with preoperative arrhythmia, isolated coronary artery bypass grafting surgery was performed in 19,497 patients. Of these, 5,547 (28.5%) developed POAF. Patients with POAF were generally older (mean age 69 vs 65 years, p <0.001) and presented more often with co-morbidities including congestive heart failure (p <0.001), hypertension (p <0.001), cerebrovascular disease (p <0.001), and renal failure (p = 0.046). Patients with POAF demonstrated a greater 30-day mortality on univariate analysis but not on multivariate analysis (p = 0.376). Patients with POAF were, however, at an independently increased risk of perioperative complications including permanent stroke (p <0.001), new renal failure (p <0.001), infective complications (p <0.001), gastrointestinal complications (p <0.001), and return to the theater (p <0.001). POAF was also independently associated with shorter long-term survival (p = 0.002). In conclusion, POAF is a risk factor for short-term morbidity and decreased long-term survival. Rigorous evaluation of various therapies that prevent or decrease the impact of POAF is imperative. Moreover, patients who develop POAF should undergo strict surveillance and be routinely screened for complications after discharge.
Sex differences in outcomes following isolated coronary artery bypass graft surgery in Australian patients: Analysis of the Australasian Society of Cardiac and Thoracic Surgeons cardiac surgery database
Publisher: Oxford University Press (OUP)
Date: 11-11-2012
DOI: 10.1093/EJCTS/EZR039
Abstract: Women undergoing isolated coronary artery bypass graft (CABG) surgery have been previously shown to be at an independently increased risk for post-operative morbidity and mortality. The current study evaluates the impact of sex as an independent risk factor for early and late morbidity and mortality following isolated CABG surgery. Data obtained between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Program was retrospectively analysed. Demographic, operative data and post-operative complications were compared between male and female patients using chi-square and t-tests. Long-term survival analysis was performed using Kaplan-Meier survival curves and the log-rank test. Independent risk factors for short- and long-term mortality were identified using binary logistic and Cox regression, respectively. CABG surgery was undertaken in 21 534 patients at 18 Australian institutions 22.2% were female. Female patients were generally older (mean age, 68 vs. 65 years, P < 0.001) and presented more often with congestive heart failure (P < 0.001), hypertension (P < 0.001), diabetes mellitus (P < 0.001) and cerebrovascular disease (P < 0.001). Women demonstrated a greater 30-day mortality (2.2% vs. 1.5%, P < 0.001) on univariate analysis but not on multivariate analysis (P = 0.638). Similarly, women demonstrated a greater late mortality than men on univariate analysis (P = 0.006) but not on multivariate analysis (P = 0.093). Women had a decreased risk of early complications including new renal failure (P = 0.001) and deep sternal wound infection (P = 0.017) but were more likely to require red blood cell transfusion (P < 0.001). Female patients undergoing isolated CABG surgery have a greater 30-day mortality which may be accounted for by a poorer pre-operative risk factor profile. Further investigation is required into the reasons for differential outcome after CABG based on sex.
Impact of graft ischemic time on outcomes after bilateral sequential single-lung transplantation
Publisher: Elsevier BV
Date: 06-1999
DOI: 10.1016/S0003-4975(99)00309-4
Abstract: Graft ischemic time (GIT) is a potential limiting factor in lung transplantation. Seventy-four patients who underwent bilateral sequential single-lung transplantation were ided into three groups: group I, GIT less than 5 hours (n = 20) group II, GIT between 5 and 8 hours (n = 39) and group III, GIT more than 8 hours (n = 15). We compared early allograft function (ratio of arterial oxygen tension to inspired oxygen fraction and alveolar-arterial oxygen gradient), blood loss, the need for tracheostomy, the duration of ventilation, intensive care unit stay, and hospital stay. We also compared prevalences of acute and chronic rejection, airway complications, lung function test, and 2-year survival. Early allograft function in group III was significantly worse than those in groups I and II. However, there was no significant difference in any other variables of early and medium-term outcomes among the three groups. No significant correlation was detected between GIT and duration of intensive care unit stay or hospital stay. The limitation of acceptable GIT could be extended from the traditionally approved 4 to 5 hours, to 5 to 8 hours or even longer.
Motion tracking control of piezo-driven flexure-based mechanism based on sliding mode strategy
Publisher: IEEE
Date: 2007
Robust neural network motion tracking control of piezoelectric actuation systems for micro/nanomanipulation
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 02-2009
Tumour necrosis factor-alpha stimulates human neutrophils to release preformed activin A
Publisher: Wiley
Date: 29-03-2011
DOI: 10.1038/ICB.2011.12
Abstract: Activin A, a member of the transforming growth factor-β superfamily, is a critical early mediator of acute inflammation. Activin A release coincides with the release of tumour necrosis factor-α (TNF-α) in models of lipopolysaccharide (LPS)-induced inflammation. The source of circulating activin A during acute inflammation has not been identified and the potential contribution of leukocyte subsets was examined in the following study. Human leukocytes from healthy volunteers were fractionated using Ficoll gradients and cultured under serum-free conditions. Freshly isolated human neutrophils contained 20-fold more activin A than blood mononuclear cells as measured by enzyme-linked immunosorbent assay (ELISA), and both dimeric and monomeric forms of activin A were detected in these cells by western blotting. Activin A was predominantly immunolocalized in the neutrophil cytoplasm. Purified neutrophils secreted activin A in culture when stimulated by TNF-α, but were unable to respond to LPS directly. Although TNF-α stimulated activin A release from neutrophils within 1 h, activin subunit mRNA expression did not increase until 12 h of culture, and the amount of activin A released following TNF-α stimulation did not change between 1 and 12 h. Specific inhibition of the p38 MAP kinase signalling pathway blocked TNF-α-induced activin release, and the secretion of activin A was not due to TNF-α-induced neutrophil apoptosis. These data provide the first evidence that neutrophils are a significant source of mature, stored activin A. Stimulation of the release of neutrophil activin A by TNF-α may contribute to the early peak in circulating activin A levels during acute inflammation.
Off-pump coronary artery bypass grafting: Is there a role in elderly patients?
Publisher: Wiley
Date: 07-2003
Major Complications Related to the Use of Transesophageal Echocardiography in Cardiac Surgery
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1053/J.JVCA.2008.09.014
Abstract: The purpose of this study was to determine the incidence of injury associated with transesophageal echocardiography (TEE injuries) in cardiac surgery. Retrospective. University-affiliated hospitals. Four thousand seven hundred eighty-four patients, 89% of all public hospital cardiac surgery patients in Victoria, from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) database undergoing cardiac surgery with TEE between July 1, 2005, and June 30, 2007. Because ASCTS did not record TEE use before July 2005, it was assumed that 89% of an additional 11,719 cardiac surgery patients between July 2001 and June 2005 also had TEE. The authors searched the ASCTS database for cardiac surgery patients who also had endoscopy and/or noncardiac surgery. The files of these patients were screened for possible esophageal or gastric tears or perforations. An expert panel determined likely TEE injuries. There were 6 TEE complications from July 1, 2005, to June 30, 2007 (13/10,000 patients). There were a further 8 TEE complications before June 30, 2005, an extrapolated overall rate of 9/10,000 TEE (95% confidence interval, 5-16/10,000). TEE complications were more frequent in patients more than 70 years old (relative risk [RR], 3.7 p = 0.03) and women (RR, 6.5 p < 0.001). Three patients with TEE injury died (2/10,000). TEE is associated with an incidence of major injuries of about 1 per 1,000 patients, with older women having a much higher risk. TEE use in cardiac surgery should be evaluated in the light of practice guidelines and morbidity and mortality data and not considered routine.
Related Organisations
Cardiac Society Of Australia And New Zealand
Location: No location found
Royal College Of Surgeons Of Edinburgh
Location: United Kingdom of Great Britain and Northern Ireland
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View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0347024
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