ORCID Profile
0000-0001-7149-8895
Current Organisation
Royal Brisbane and Women's Hospital
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Wiley
Date: 31-05-2017
Abstract: The Australasian College for Emergency Medicine requires 15 proctored examinations of the aorta for credentialing in ultrasonography for abdominal aortic aneurysm (AAA). Furthermore, at least three examinations need to be positive for an aneurysm. In the ED where AAA presentations are sporadic, what are the chances that an emergency physician (EP) will have the opportunity to demonstrate three AAAs in the next 12 months? The probability of an event occurring within a given time-frame can be modelled by the Poisson distribution. Central to the Poisson distribution is the infrequency of the event such as encountering an AAA in the ED. An EP working 30 clinical hours/week in our tertiary-referral hospital ED can be expected to encounter 15.6 (3.6 symptomatic + 12 asymptomatic) AAA in the next 12 months. The probability of seeing three or more cases during this time is 99.9%. Assuming a proctor can be found for half the cases, the probability of an EP performing proctored ultrasound examinations in at least three AAAs is 98%. This probability drops to 89% if a proctor can be found for only one-third of cases. For an EP to be almost 100% certain of meeting the credentialing requirements, he/she would need almost 10 proctored ultrasound cases of AAA to be available within his/her shifts during the year. The Poisson distribution has enabled us to model the probability of encountering a given number of AAA in the ED. Analysis such as this may help rationalise the numbers needed for credentialing.
Publisher: Elsevier BV
Date: 12-2013
DOI: 10.1016/J.RESP.2013.08.015
Abstract: It is unclear whether the failure to reverse bronchoconstriction with deep inspiration (DI) in asthma is due to reduced maximal dilatation of the DI. We compared the effect of different DI volumes on maximal dilatation and reversal of bronchoconstriction in nine asthmatics and ten non-asthmatics. During bronchoconstriction, subjects took DI to 40%, 70% and 100% inspiratory capacity, on separate days. Maximal dilatation was measured as respiratory system resistance (Rrs) at end-inspiration and residual dilatation as Rrs at end-expiration, both expressed as percent of Rrs at end-tidal expiration prior to DI. DI volume was positively associated with maximal dilatation in non-asthmatics (ANOVA p=0.055) and asthmatics (p=0.023). DI volume was positively associated with residual dilatation in non-asthmatics (p=0.004) but not in asthmatics (p=0.53). The degree of maximal dilatation independently predicted residual dilatation in non-asthmatics but not asthmatics. These findings suggest that the failure to reverse bronchoconstriction with DI in asthma is not due to reduced maximal dilatation, but rather due to increased airway narrowing during expiration.
Publisher: Elsevier BV
Date: 09-2011
Abstract: It is unclear why obesity is associated with worse asthma control. We hypothesized that (1) obesity affects asthma control independent of spirometry, airway inflammation, and airway hyperresponsiveness (AHR) and (2) residual symptoms after resolution of inflammation are due to obesity-related changes in lung mechanics. Forty-nine subjects with asthma underwent the following tests, before and after 3 months of high-dose inhaled corticosteroid (ICS) treatment: five-item asthma control questionnaire (ACQ-5), spirometry, fraction of exhaled nitric oxide (Feno), methacholine challenge, and the forced oscillation technique, which allows for the calculation of respiratory system resistance (Rrs) and respiratory system reactance (Xrs) as indicators of airway caliber and elastic load, respectively. The effects of treatment were assessed by BMI group (18.5-24.9, 25-29.9, and ≥ 30 kg/m²) using analysis of variance. Multiple regression analyses determined the independent predictors of ACQ-5 results. At baseline, the independent predictors of ACQ-5 results were FEV(1), Feno, and BMI (model r² = 0.38, P < .001). After treatment, asthma control, spirometry, airway inflammation, and AHR improved similarly across BMI groups. The independent predictors of ACQ-5 results after treatment were Rrs and BMI (model r² = 0.42, P < .001). BMI is a determinant of asthma control independent of airway inflammation, lung function, and AHR. After ICS treatment, BMI again predicts ACQ-5 results, but independent of obesity-related changes in lung mechanics.
Publisher: European Respiratory Society (ERS)
Date: 05-2005
DOI: 10.1183/09031936.05.00104504
Abstract: Increased wheeze and asthma diagnosis in obesity may be due to reduced lung volume with subsequent airway narrowing. Asthma (wheeze and airway hyperresponsiveness), functional residual capacity (FRC) and airway conductance (Gaw) were measured in 276 randomly selected subjects aged 28-30 yrs. Data were initially adjusted for smoking and asthma before examining relationships between weight and FRC (after adjustment for height), and between body mass index (BMI = weight.height(-2)) and Gaw (after adjustment for FRC) by multiple linear regression, separately for females and males. For males and females, BMI (+/-95% confidence interval) was 27.0+/-4.6 kg.m(-2) and 25.6+/-6.0 kg.m(-2) respectively, Gaw was 0.64+/-0.04 L.s(-1).cmH2O(-1) and 0.57+/-0.03 L.s(-1).cmH2O(-1), and FRC was 85.3+/-3.4 and 84.0+/-2.9% of predicted. Weight correlated independently with FRC in males and females. BMI correlated independently and inversely with Gaw in males, but only weakly in females. In conclusion, obesity is associated with reduced lung volume, which is linked with airway narrowing. However, in males, airway narrowing is greater than that due to reduced lung volume alone. The mechanisms causing airway narrowing and sex differences in obesity are unknown.
Publisher: Elsevier BV
Date: 10-2014
Abstract: Pediatric asthma lacks sensitive objective measures for asthma monitoring. The forced oscillation technique (FOT) offers strong feasibility across the pediatric age range, but relationships between FOT parameter day-to-day variability and pediatric asthma severity and control are unknown. Day-to-day variability in FOT respiratory system resistance (Rrs) and respiratory system reactance (Xrs) compared with peak expiratory flow (PEF) were defined in 22 children with asthma (mean ± SD age, 10.4 ± 1.1 years) during a 5-day asthma c . FOT was performed at 6 Hz in triplicate on each test occasion. Relationships between day-to-day FOT variability (expressed as within-subject SD [SDW] and asthma control and severity (defined according to GINA [Global Initiative for Asthma] recommendations) were explored. For comparison, normal baseline FOT values and variability, measured on two occasions, were defined in a separate cohort of 38 healthy children (age, 9.5 ± 1.0 years). Day-to-day Rrs variability was greater in persistent (n = 16) vs intermittent (n = 6) asthma (mean SDW, 0.69 cm H2O/L/s vs 0.39 cm H2O/L/s P ≤ .01). Day-to-day Rrs variability was increased in uncontrolled (n = 13) vs partly controlled asthma (n = 9) (mean SDW, 0.75 cm H2O/L/s vs 0.42 cm H2O/L/s P ≤ .05). PEF variability did not differentiate the groups. Day-to-day variability of Rrs and Xrs but not baseline values were increased in children with asthma vs control children (Rrs mean SDW, 0.61 cm H2O/L/s vs 0.33 cm H2O/L/s [P ≤ .05] Xrs mean SDW, 0.24 cm H2O/L/s vs 0.15 cm H2O/L/s [P ≤ .05]). Increased day-to-day FOT variability exists in school-aged children with asthma. Day-to-day Rrs variability was associated with asthma severity and asthma control. FOT may be a useful objective monitoring tool in pediatric asthma and warrants further study. Australian and New Zealand Clinical Trials Registry No.: ACTRN12614000885695 URL: www.anzctr.org.au.
Publisher: Informa UK Limited
Date: 08-2010
Publisher: American Physiological Society
Date: 11-2013
DOI: 10.1152/JAPPLPHYSIOL.00093.2013
Abstract: The mechanisms underlying not well-controlled (NWC) asthma remain poorly understood, but accumulating evidence points to peripheral airway dysfunction as a key contributor. The present study tests whether our recently described respiratory system reactance (Xrs) assessment of peripheral airway dysfunction reveals insight into poor asthma control. The aim of this study was to investigate the contribution of Xrs to asthma control. In 22 subjects with asthma, we measured Xrs (forced oscillation technique), spirometry, lung volumes, and ventilation heterogeneity (inert-gas washout), before and after bronchodilator administration. The relationship between Xrs and lung volume during a deflation maneuver yielded two parameters: the volume at which Xrs abruptly decreased (closing volume) and Xrs at this volume (Xrs crit ). Lowered (more negative) Xrs crit reflects reduced apparent lung compliance at high lung volumes due, for ex le, to heterogeneous airway narrowing and unresolved airway closure or near closure above the critical lung volume. Asthma control was assessed via the 6-point Asthma Control Questionnaire (ACQ6). NWC asthma was defined as ACQ6 1.0. In 10 NWC and 12 well-controlled subjects, ACQ6 was strongly associated with postbronchodilator (post-BD) Xrs crit ( R 2 = 0.43, P 0.001), independent of all measured variables, and was a strong predictor of NWC asthma (receiver operator characteristic area = 0.94, P 0.001). By contrast, Xrs measures at lower lung volumes were not associated with ACQ6. Xrs crit itself was significantly associated with measures of gas trapping and ventilation heterogeneity, thus confirming the link between Xrs and airway closure and heterogeneity. Residual airway dysfunction at high lung volumes assessed via Xrs crit is an independent contributor to asthma control.
Publisher: Wiley
Date: 29-03-2020
DOI: 10.1111/JAN.14350
Abstract: To determine the effectiveness of therapeutic activity kits on health service use and treatment delivered in the emergency department (ED) in patients with pre‐morbid dementia. Pragmatic randomized control trial with equal parallel groups. Participants with dementia will be randomly assigned to the control group ( N = 56) or the intervention group ( N = 56). The intervention group will be given access to a therapeutic activity kit containing several different activities and sensory stimuli to engage the person with dementia during their ED stay in addition to usual care, and the control group will be given usual care only. A research nurse will observe participants at 30–60‐min intervals throughout their ED stay for responsive behaviours, one‐on‐one nursing, and the use of chemical and physical restraint. This study has received Research Ethics Committee approval from the institutional review board and funding from the Rosemary Bryant Foundation (May 2019). Emergency departments are busy and noisy environments and can be intimidating and disorientating for patients with dementia, which can result in responsive behaviours. Responsive behaviours are often managed with restrictive interventions, such as chemical or physical restraint, or with constant bedside nursing (one‐on‐one nursing) to ensure patient safety. Alternatively, non‐restrictive and non‐pharmacological interventions that ert or occupy the attention of patients such as those contained in the therapeutic activity kit can be considered as a more person‐centred strategy. Therapeutic activity kits have been reported as feasible for the use in ED however, there is limited quality evidence at present to support the implementation of such interventions in the ED. If this study is successful, it will demonstrate that a therapeutic activity kit containing activities (puzzles, colouring, music, and tactile activities) is inexpensive, easily implemented intervention that can prevent this patient group from demonstrating unsafe behaviours and requiring one‐on‐one nursing and restraints.
Publisher: Cold Spring Harbor Laboratory
Date: 19-10-2022
DOI: 10.1101/2022.10.17.22280670
Abstract: Pain is the most common symptom experienced when presenting to the emergency department (ED). Estimates indicate over half of all patients will present in pain. EDs typically focus on care process measures, such as time to first analgesic medication. Process-based metrics remove the patient from their own experience. Unfortunately, when patient-reported measures of pain care are used in the ED for quality improvement or research, they vary widely and often lack validation. Previous work has demonstrated that a modified version of the American Pain Society – Patient Outcome Questionnaire – Revised Edition (APS-POQ-R) may provide an ideal patient-reported outcome measure for the adult ED population. However, previous work has left validation incomplete. In this multi-site, multistage research, we demonstrate the construct, convergent and ergent validity and the internal consistency of a modified version of the APS-POQ-R in adult patients presenting to two large, inner-city EDs with moderate to severe acute pain. After three stages of psychometric testing in 646 patients, we present a nine-question, three construct patient-reported outcome measure for moderate to severe pain in the adult emergency department, now known as the American Pain Society – Patient Outcome Questionnaire – Revised for the ED (APS-POQ-RED). This article presents the psychometric properties of a revised version of the APS-POQ-R for use in the adult ED. This shortened, ED-specific patient-reported outcome measure (APS-POQ-RED) seeks to provide a standardised, validated measure of patient-reported outcomes of acute pain care in the ED for quality and research purposes.
Publisher: Cold Spring Harbor Laboratory
Date: 30-05-2022
DOI: 10.1101/2022.05.29.22275652
Abstract: Accurate, reliable and efficient measures of pain-related presentations are essential to evaluate and improve pain care in the ED. Estimates of pain prevalence on arrival to the emergency department (ED) vary depending on the methods used. Artificial intelligence (AI) approaches are likely to be the future for identifying patients in pain from electronic health records (EHR). However, we need a robust method to identify these patients before this can occur. This study aims to identify patients presenting in pain to the ED using binary classification and to describe the population, treatment and outcomes. This study employs a cross-sectional design using retrospective data routinely collected in the EHR at a single ED. A random s le of 10 000 patients was selected for inclusion over three years. Triage nursing assessment underwent binary classification by three expert clinicians. The prevalence of pain on arrival is the primary outcome. Patients with pain were compared to those without pain on arrival regarding demographics, treatment and outcomes. The prevalence of pain on arrival was 55.2% (95%CI 54.2% - 56.2%). Patients who presented in pain differed from those without pain in terms of age, country of birth, socioeconomic status, mode of arrival, urgency and discharge destination. The median time to first analgesic medication was 65min (IQR 38 – 114 min), and 45.6% (95% CI 44.3% - 46.9%) of patients arriving in pain received analgesic medication. The prevalence of pain on arrival compares well with previously reported figures using similar methods. Differences in the cohort presenting in pain compared to the population may represent differences in the prevalence or be an extension of previous bias seen in the documentation of pain. This work has set a rigorous methodology for identifying patients presenting with pain from the EHR. It will form the basis for future applications of AI to identify patients presenting in pain to the ED.
Publisher: Wiley
Date: 05-02-2018
Publisher: Wiley
Date: 25-09-2023
Abstract: COVID‐19 greatly disrupted the provision of emergency care across the globe. ED service delivery was urgently redesigned as human and material resources were mobilised, and patients with respiratory symptoms were isolated. This study aimed to compare ED patient volume and flow metrics before and during the COVID‐19 pandemic. An observational study was conducted in two large urban EDs in Brisbane, Australia and Seoul, Republic of Korea. Patient volume and flow were quantified using ED presentation numbers and service times, respectively. Daily case numbers, waiting, treatment and admission delay times were compared between 2019 and 2020/2021 using time series plots. Outcomes were further classified by triage category and age group. Trends were examined alongside a timeline of health service and government policies. There were reductions in daily presentations for the least urgent triage categories during the early phase of the pandemic. The caseloads for the most urgent triage categories were unaffected. The trends were similar in both EDs. A reduction in waiting and admission delay times but not treatment times coincided with reduced presentations in Brisbane. This pattern gradually reversed as presentations returned to baseline. In Seoul, admission delay times returned to pre‐pandemic levels despite a persistent reduction in presentation numbers. Total daily presentations varied considerably according to government mandated social restrictions and testing requirements in both EDs. The reductions in waiting and admission delay times corresponded with improvements in hospital capacity.
Publisher: MDPI AG
Date: 09-05-2020
DOI: 10.3390/JCM9051406
Abstract: This study was conducted to determine whether overcrowding in the emergency department (ED) affects the occurrence of a return visit (RV) within 72 h. The crowding indicator of index visit was the average number of total patients, patients under observation, and boarding patients during the first 1 and 4 h from ED arrival time and the last 1 h before ED departure. Logistic regression analysis was conducted to determine whether each indicator affects the occurrence of RV and post-RV admission. Of the 87,360 discharged patients, 3743 (4.3%) returned to the ED within 72 h. Of the crowding indicators pertaining to total patients, the last 1 h significantly affected decrease in RV (p = 0.0046). Boarding patients were found to increase RV occurrence during the first 1 h (p = 0.0146) and 4 h (p = 0.0326). Crowding indicators that increased the likelihood of admission post-RV were total number of patients during the first 1 h (p = 0.0166) and 4 h (p = 0.0335) and evaluating patients during the first 1 h (p = 0.0059). Overcrowding in the ED increased the incidence of RV and likelihood of post-RV admission. However, overcrowding at the time of ED departure was related to reduced RV.
Publisher: Wiley
Date: 07-11-2017
Publisher: BMJ
Date: 27-10-2011
Publisher: Wiley
Date: 26-02-2018
Abstract: Gender equality and workforce ersity has recently been in the forefront of College discussions. Reasons for the difference between various groups may not be as they initially appeared. The results of comparing the outcome between two groups can sometimes be confounded and even reversed by an unrecognised third variable. This concept is known as Simpson's Paradox, and is illustrated here using a renowned case study on potential gender bias for acceptance to Graduate School at the University of California, Berkeley. The investigation showed that males were 1.8 times more likely to be admitted to Graduate School than females in 1973. Initially it appeared that women were discriminated against in the selection process. However, when admissions were re-examined at in idual Departments of the School, admission tended to be better for women than men in four of six Departments. This contradiction or paradox tells us that the association between admission and gender was dependent upon on Department. The confounding effect of Department was defined by two characteristics. Firstly, a strong association between Department and admission: some Departments admitted much smaller percentages of applicants than others. Secondly, a strong association between Department and gender: females tended to apply to Departments with lower admission rates. The explanation of differences between groups can be multifactorial. A search for possible confounders will assist in this understanding. This could apply whenever two groups initially appear to differ, but on closer analysis this difference is either unfounded, or even reversed by reference to a third, confounding variable.
Publisher: Emerald
Date: 14-05-2018
DOI: 10.1108/JICA-02-2018-0015
Abstract: Patient dependence on an emergency department (ED) for ongoing, non-urgent health care is a complex issue related to poor mental and physical health, disability, previous trauma, social disadvantage and lack of social supports. Working Together to Connect Care is an innovative program that provides an assertive community case management approach coupled with an ED management plan to support people who frequently attend the Royal Brisbane and Women’s Hospital ED. The program, which is yet to be fully evaluated, currently helps to manage a large number of patients with a wide variety of complex needs. To demonstrate the scope and capabilities of the program, the purpose of this paper is to present a series of case studies of patients who frequently attended the ED and subsequently became program participants. A series of five case studies is used to illustrate the variety of patient characteristics and available management pathways. Outcomes, including rates of ED attendance, at five months after program commencement are also described. The variety of characteristics and experiences of the patients in the case studies is representative of the program cohort as a whole. Program participation has resulted in improved patient outcomes as demonstrated by crisis resolution, housing stability, engagement with primary health care and reduced frequency of ED presentations. A personalized, integrated-care management approach is both flexible and effective in responding to the complex needs of five patients who frequently attend EDs.
Publisher: European Respiratory Society (ERS)
Date: 07-2003
DOI: 10.1183/09031936.03.00117502
Abstract: After bronchoconstriction, deep inspiration (DI) causes dilatation followed by airway re-narrowing. Re-narrowing may be faster in asthmatic than nonasthmatic subjects. This study investigated the relationship between re-narrowing and the magnitude of both DI-induced dilatation and the volume-dependence of respiratory system resistance (Rrs) during tidal breathing. In 25 asthmatic and 18 nonasthmatic subjects the forced oscillation technique was used to measure Rrs at baseline and after methacholine challenge, during 1 min of tidal breathing, followed by DI to total lung capacity (TLC) and passive return to functional residual capacity (FRC). Dilatation was measured as the decrease in Rrs between end tidal inspiration and TLC, re-narrowing as Rrs at FRC immediately after DI, as per cent Rrs at end-tidal expiration, and volume dependent tidal fluctuation as the difference between mean Rrs at end-expiration and end-inspiration. Asthmatic subjects had greater re-narrowing, less dilatation, and greater tidal fluctuations both at baseline and after challenge. Re-narrowing correlated with baseline tidal fluctuation and inversely with dilatation. Both baseline tidal fluctuation and dilatation were significant independent predictors of re-narrowing. Following deep inspiration-induced dilatation, faster airway re-narrowing in asthmatic than nonasthmatic subjects is associated not only with reduced deep inspiration-induced dilatation but also with some property of the airways that is detectable prior to challenge as an increased volume dependence of resistance.
Publisher: Elsevier BV
Date: 12-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 26-08-2019
Publisher: American Thoracic Society
Date: 15-07-2007
Publisher: Elsevier BV
Date: 10-2011
DOI: 10.1016/J.PUPT.2011.03.006
Abstract: The lungs are in a constant state of motion. The dynamic nature of tidal breathing, whereby cycles of pressure changes across the lungs cause the chest wall, lung tissue and airways to repeatedly expand and contract, ventilates the lung tissue and allows respiration to occur. However, these regular cycles of tidal inspirations and expirations are punctuated by breaths of differing volumes, most particularly periodic deep inspirations. In normal, healthy subjects, these deep inspirations have a dual effect in reducing airway responsiveness. Firstly, deep inspirations taken under baseline conditions protect the airways against subsequent bronchoconstriction, termed DI bronchoprotection. Secondly, deep inspirations are able to dramatically reverse bronchoconstriction. The ability for deep inspirations to reverse bronchoconstriction appears to be due to both the ability to dilate the airways with a full inspiration to total lung capacity (TLC) and the rate at which the airways re-narrow once tidal breathing is resumed. Deep inspiration reversal is reduced in subjects with asthma and is due both to a reduced ability to dilate the airways as well as an increase in the rate of re-narrowing. On the other hand, DI bronchoprotection is completely absent in asthma. Although the mechanisms behind these abnormalities remain unclear, the inability for deep inspirations to both protect against and fully reverse bronchoconstriction in patients with asthma appears critical in the development of airway hyperresponsiveness. As such, determining the pathophysiology responsible for the malfunction of deep inspirations in asthma remains critical to understanding the disease and is likely to pave the way for novel therapeutic targets.
Publisher: Elsevier BV
Date: 07-2010
DOI: 10.1016/J.RESP.2010.05.013
Abstract: To determine reference equations for respiratory system resistance and reactance in a large randomly selected s le from a general, predominantly Caucasian population. A prospective respiratory health survey of the general population in Busselton, Western Australia, was conducted between 2005 and 2007. Subjects had measures of spirometry, and resistance and reactance at 6, 11, 19 Hz. Eligible subjects were never smokers, with no history of respiratory disease, no symptoms of cough, shortness of breath or chest tightness in the previous 12 months, and no respiratory tract infections in the previous 4 weeks. 904 Eligible subjects (341 male) aged 18-92 years had technically satisfactory measurements. Reference equations were established for males and females separately. Both resistance and reactance were predicted by height and weight. Age was a predictor of reactance only. These data provide reference equations for forced oscillatory parameters, in well-characterized Caucasian subjects, with no respiratory symptoms, from a large general population.
Publisher: Informa UK Limited
Date: 05-2015
DOI: 10.2147/COPD.S78332
Publisher: Cold Spring Harbor Laboratory
Date: 18-09-2020
DOI: 10.1101/2020.09.15.20194738
Abstract: 3. Pain is a common presenting complaint to the emergency department (ED), yet is often undertreated. When assessing the outcomes of pain care in the ED, process measures are commonly reported. Attempts to measure patient-reported outcomes existing in current ED literature. However, they are frequently unvalidated and lack standardization. The American Pain Societies – Patient Outcome Questionnaire-Revised edition (APS-POQ-R) has been identified as the most likely, pre-existing tool to be useful in the acute pain in the ED. However, this requires feasibility and construct validation before use. To assess the feasibility and construct validity of the APS-POQ-R in patients presenting to the adult emergency department with acute pain. This study is an initial psychometric evaluation of the constructs contained within the APS-POQ-R in adult patients presenting with moderate to severe acute pain to a large urban ED. The study is guided by the methods described in the initial development of the instrument. Two hundred adult patients were recruited and completed the APS-POQ-R. The APS-POQ-R demonstrated content validity in patients presenting with acute pain. Exploratory factor analysis demonstrated five subgroups. The tool demonstrated discriminatory ability based on patient urgency, and subscale measurement was associated with patient satisfaction with care. The APS-POQ-R has demonstrable construct validity in adult patients presenting with acute pain to the ED. Further psychometric analysis across multiple EDs is required before the APS-POQ-R can be recommended as a validated PROM for ED patients in pain.
Publisher: Wiley
Date: 26-09-2023
DOI: 10.1002/BCO2.192
Publisher: Elsevier BV
Date: 02-2012
DOI: 10.1016/J.JACI.2011.11.017
Abstract: The clinical relevance of increased ventilation heterogeneity, a marker of small-airways disease, in asthmatic patients is unclear. Ventilation heterogeneity is an independent determinant of airway hyperresponsiveness (AHR), improves with bronchodilators and inhaled corticosteroids (ICSs), and worsens during exacerbations, but its relationship to asthma control is unknown. We sought to determine the association between ventilation heterogeneity and current asthma control before and after ICS treatment. Adult subjects with asthma had lung function and asthma control (5-item Asthma Control Questionnaire [ACQ-5 score] ≥1.5 = poorly controlled, ACQ-5 score ≤0.75 = well controlled) measured at baseline. A subgroup with AHR had repeat measurements after 3 months of high-dose ICS treatment. The indices of ventilation heterogeneity in the regions of the lung where gas transport occurs predominantly through convection (ventilation heterogeneity in convection-dependent airways [Scond]) and through diffusion (ventilation heterogeneity in diffusion-dependent airways [Sacin]) were derived by using the multiple-breath nitrogen washout technique. At baseline (n = 105), subjects with poorly controlled asthma had worse FEV(1), fraction of exhaled nitric oxide measured at 200 mL/s (Feno), Scond, and Sacin values. In the treatment group (n = 50) spirometric, Feno, residual volume (RV)/total lung capacity (TLC), AHR, and Scond values significantly improved. Asthma control also improved (mean ACQ-5 score, 1.3-0.7 P < .0001). The change in ACQ-5 score correlated with changes in Feno (r(s) = 0.31, P = .03), Sacin (r(s) = 0.32, P = .02), and Scond (r(s) = 0.41, P = .003) values. The independent predictors of a change in asthma control were changes in Scond and Sacin values (model r(2) = 0.20, P = .005). Current asthma control is associated with markers of small-airways disease. Improvements in ventilation heterogeneity with anti-inflammatory therapy are associated with improvements in symptoms. Sensitive measures of small-airway function might be useful in monitoring the response to therapy in asthmatic subjects.
Publisher: Elsevier BV
Date: 06-2021
Publisher: Springer Science and Business Media LLC
Date: 24-12-2011
DOI: 10.1007/S10439-010-0206-0
Abstract: A new technique has been developed to determine in vivo airway compliance in humans that is specific to airway size and transpulmonary pressure, and can be represented as a three-dimensional surface. As yet, the ability of this technique to detect changes in specific airway compliance with disease status has not been demonstrated. The aim of this study was to assess whether this technique could determine changes in airway compliance which are thought to occur with altered smooth muscle tone in adults with asthma. Airway compliance was measured and displayed as a surface in adults with asthma before and after a reduction in smooth muscle tone by bronchodilator administration. Compliance, with respect to airway size, was calculated at three specific lung volumes functional residual capacity (FRC), total lung capacity (TLC), and midway between FRC and TLC (MID). After bronchodilator, airway compliance increased at FRC and MID in the smaller airways (<3 mm). Furthermore, airway compliance under both conditions was greater in the smaller airways compared to the larger airways. In conclusion, our method may have future utility in assessing changes in airway compliance in respiratory diseases such as asthma.
Publisher: Elsevier BV
Date: 07-2011
DOI: 10.1016/J.RESP.2011.02.004
Abstract: Forced oscillation technique (FOT) parameters are less repeatable than spirometry, and the impact of technical factors, such as data acquisition and data filtering, are unknown. FOT was performed, in triplicate, on 48 children (8-11 years) and repeated two weeks later. We examined the separate effects of monitoring tidal volume (V(T)) prior to measurement and length of data acquisition on measurement repeatability. We compared the effects on repeatability of a filtering technique in which complete breaths containing respiratory artefact were rejected and statistical filters in which outlying data points were rejected. Within- and between-session repeatability of respiratory system resistance (Rrs) and reactance (Xrs) were assessed using coefficient of variation (CV) and intra-class correlation coefficient (ICC). Longer data acquisition reduced CV of Rrs and Xrs (60s vs. shorter durations, p ≤ 0.001). Monitoring V(T) reduced CV of Rrs (p = 0.05). Complete breath filtering improved CV and ICC for both Rrs and Xrs. The repeatability of FOT measurements can be improved by optimising data acquisition and filtering.
Publisher: IOP Publishing
Date: 23-07-2004
DOI: 10.1088/0967-3334/25/4/022
Abstract: The measurement of airway stiffness is an important tool for studying airway remodelling in asthma. The relationship between airway calibre and lung volume (airway distensibility) was measured by forced oscillation technique (FOT) and compared with that measured by single-breath nitrogen washout (SBNW). In four non-asthmatic healthy subjects and three asthmatics, anatomical dead space (VDF) was measured by SBNW and respiratory system conductance (Grs) was measured by FOT at 6 Hz. During SBNW testing, 0.51 oxygen boluses were inhaled from three different lung volumes: functional residual capacity (FRC), 11 above FRC and near total lung capacity (TLC). Following inhalation of the oxygen bolus subjects exhaled to residual volume and then inhaled to TLC. During FOT, subjects breathed 0.5-1.01 tidal volumes but with gradually increasing end-expiratory lung volume until close to TLC, then returned to normal breathing before inhaling to TLC. This was also repeated but with reducing lung volume from TLC. Absolute lung volumes were measured by body plethysmography and related to volumes during FOT and SBNW by reference to TLC obtained at the end of each SBNW or FOT test manoeuvre. Distensibility was calculated as the linear regression slopes of VDF or Grs versus lung volume. Distensibility measured by VDF ranged 16-37 ml 1(-1) lung volume and by Grs it ranged 0.06-0.19 1 s(-1) cmH2O(-1) 1(-1) lung volume. Both distensibility measurements were correlated (Pearson's R2 = 0.91, p = 0.001). The SBNW and FOT are comparable methods for measuring airway distensibility and may have similar clinical usefulness. However, further studies are required to make any specific inferences about the relationship between airway distensibility by FOT and airway remodelling.
Publisher: BMJ
Date: 20-12-2019
DOI: 10.1136/EMERMED-2018-207876
Abstract: Variation in the approach to the patient with a possible subarachnoid haemorrhage (SAH) has been previously documented. The purpose of this study was to identify factors that influence emergency physicians’ decisions about diagnostic testing after a normal CT brain scan for ED patients with a headache suspicious of a SAH. We conducted an interview-based qualitative study informed by social constructionist theory. Fifteen emergency physicians from six EDs across Queensland, Australia, underwent in idual face-to-face or telephone interviews. Content analysis was performed whereby transcripts were examined and coded independently by two co-investigators, who then jointly agreed on the influencing factors. Six categories of influencing factors were identified. Patient interaction was at the forefront of the identified factors. This shared decision-making process incorporated ‘what the patient wants’ but may be biased by how the clinician communicates the benefits and harms of the diagnostic options to the patient. Patient risk profile, practice evidence and guidelines were also important. Other influencing factors included experiential factors of the clinician, consultation with colleagues and external influences where practice location and work processes impose constraints on test ordering external to the preferences of the clinician or patient. The six categories were organised within a conceptual framework comprising four components: the context, the evidence, the experience and the decision. When clinicians are faced with a diagnostic challenge, such as the workup of a patient with suspected SAH, there are a number of influencing factors that can result in a variation in approach. These need to be considered in approaches to improve the appropriateness and consistency of medical care.
Publisher: Elsevier BV
Date: 07-2012
DOI: 10.1016/J.JACI.2012.02.015
Abstract: Asthma guidelines recommend inhaled corticosteroid (ICS) dose titration for patients on the basis of an assessment of current asthma control. However, the physiological determinants of asthma symptom control are poorly understood and spirometry is a poor predictor of symptomatic response. To determine the role of small airway measurements in predicting the symptom response following ICS dose titration. Adult asthmatic patients had the Asthma Control Questionnaire (ACQ) scores and lung function measured at baseline and after 8 weeks. Tests included spirometry, plethysmography, sputum cell count, exhaled nitric oxide, airway hyperresponsiveness to mannitol, respiratory system mechanics using the forced oscillation technique, and ventilation heterogeneity using the multiple breath nitrogen washout. The parameters ventilation heterogeneity in convection-dependent airways and ventilation heterogeneity in diffusion-dependent airways were derived as measures of ventilation heterogeneity in the small airways. The dose of ICS was doubled if the ACQ score was greater than or equal to 1.5 (uptitration) and quartered if the ACQ score was less than 1.5 (downtitration). The relationships between baseline physiological parameters and the change in the symptom-only 5-item ACQ (deltaACQ-5) were examined by using Spearman correlations, forward stepwise linear regressions, and receiver operator curve analyses. ICS dose uptitration (n= 20) improved ACQ-5 scores (1.76 to 1.16 P= .04). Baseline fraction of exhaled nitric oxide (r= -0.55 P= .01) and ventilation heterogeneity in convection-dependent airways (r= -0.64 P= .002) correlated with deltaACQ-5, but ventilation heterogeneity in convection-dependent airways was the only independent predictor (r(2) = 0.34 P = 0.007). ICS dose downtitration (n= 41) worsened ACQ-5 scores (0.46 to 0.80 P< .001), with 29% of the patients having a deltaACQ-5 of greater than 0.5. Only baseline ventilation heterogeneity in diffusion-dependent airways correlated with deltaACQ-5 (r= 0.40 P= .009) and identified subjects with deltaACQ-5 of greater than 0.5 (receiver operator curve area under the curve= 0.78 P= .0003). Ventilation heterogeneity predicts symptomatic responses to ICS dose titration. Worse small airways function predicts symptomatic improvement to ICS dose uptitration and loss of symptom control during downtitration.
Publisher: Wiley
Date: 2022
Abstract: To determine the burden, on the ED, of harm from unintentional adverse drug events (ADEs) in the community. A retrospective, observational study of 936 randomly selected presentations to a level 6 ED at a principal referral hospital in Brisbane, Australia, in November 2017. Clinical records were screened by a pharmacist, who identified suspected ADEs. All suspected ADEs and a random selection of presentations without ADEs were reviewed by an expert panel, which classified, by consensus: occurrence and type of ADE, contribution of ADE to presentation, severity of harm and preventability of presentation. Medication‐related ED presentations (ADE‐Ps) and potential ADEs were, respectively, defined as presentations directly attributable to an ADE, and medication events that occurred but did not cause the ED presentation. Descriptive data analysis was performed. The median (interquartile range) age of patients was 40 (27–58) years, with 49.7% (95% confidence interval [CI] 46.5–52.9) being male. The prevalences of ADE‐Ps and potential ADEs were 9.2% (95% CI 7.5–11.3) and 5.0% (95% CI 3.8–6.6), respectively. The severity of harm was classified as ‘death or likely permanent harm’ in 4.7% (95% CI 0.2–9.1) of ADE‐Ps, ‘temporary harm’ (89.5%, 95% CI 83.1–96.0) and ‘minimal or no harm’ (5.8%, 95% CI 0.9–10.8). Most (79.1%, 95% CI 70.5–87.7) ADE‐Ps were preventable. There is a high burden on emergency care because of unintended medication harm in the community. Interventions to reduce such harm are likely to require a co‐ordinated primary, acute and public healthcare response. The high proportion of presentations with potential ADEs indicates opportunity for harm mitigation in the ED.
Publisher: Wiley
Date: 09-10-2020
DOI: 10.1111/JAN.14216
Abstract: To determine the association between time to first analgesic medication and emergency department length of stay (ED LOS). Retrospective cohort study. We conducted this study in a large, inner-city emergency department and included adult patients who presented with pain as a symptom and received analgesic medication(s). Study participants were identified from a random selection of 2,000 adult patients who presented between August-October 2018. The relationship between ED LOS and time to first analgesic medication was described using bivariate and multivariate linear regression. Of the 2,000 randomly selected patients presenting between August and October 2018, 727 (36.35%) had pain as a symptom on arrival, 423 (21.15%) had analgesic medication administered. The median time to first analgesic medication was in 62 (interquartile range: 36-105) minutes and median ED LOS was 218 (interquartile range: 160-317.5) minutes. After adjusting for the effects of sex, urgency of the presentation, emergency department location first seen by clinician, departure destination and workload metrics (average daily time to be seen and daily access block). Time to first analgesic medication was independently associated with ED LOS, contributing to 6.96% of the variance in the multivariate model. Providing analgesic medication faster to patients presenting in pain, in addition to previously demonstrated positive patient outcomes, may decrease their ED LOS. Reducing ED LOS through faster pain care, benefits the patient through faster pain relief and can benefit the department by reducing the total amount of care delivered in the emergency department. Reducing total care delivery frees up resources to improve the care to all emergency department patients.
Publisher: American Physiological Society
Date: 05-2012
DOI: 10.1152/JAPPLPHYSIOL.01259.2011
Abstract: Airway distensibility appears to be unaffected by airway smooth muscle (ASM) tone, despite the influence of ASM tone on the airway diameter-pressure relationship. This discrepancy may be because the greatest effect of ASM tone on airway diameter-pressure behavior occurs at low transpulmonary pressures, i.e., low lung volumes, which has not been investigated. Our study aimed to determine the contribution of ASM tone to airway distensibility, as assessed via the forced oscillation technique (FOT), across all lung volumes with a specific focus on low lung volumes. We also investigated the accompanying influence of ASM tone on peripheral airway closure and heterogeneity inferred from the reactance versus lung volume relationship. Respiratory system conductance and reactance were measured using FOT across the entire lung volume range in 22 asthma subjects and 19 healthy controls before and after bronchodilator. Airway distensibility (slope of conductance vs. lung volume) was calculated at residual volume (RV), functional residual capacity (FRC), and total lung capacity. At baseline, airway distensibility was significantly lower in subjects with asthma at all lung volumes. After bronchodilator, distensibility significantly increased at RV (64.8%, P 0.001) and at FRC (61.8%, P 0.01) in subjects with asthma but not in control subjects. The increased distensibility at RV and FRC in asthma were not associated with the accompanying changes in the reactance versus lung volume relationship. Our findings demonstrate that, at low lung volumes, ASM tone reduces airway distensibility in adults with asthma, independent of changes in airway closure and heterogeneity.
Publisher: European Respiratory Society (ERS)
Date: 09-09-2021
DOI: 10.1183/23120541.00439-2021
Abstract: We aimed to determine normal thresholds for positive bronchodilator responses for oscillometry in an Australian general population s le aged ≥40 years, to guide clinical interpretation. We also examined relationships between bronchodilator responses and respiratory symptoms, asthma diagnosis, smoking and baseline lung function. Subjects recruited from Sydney, Melbourne and Busselton, Australia, underwent measurements of spirometry, resistance ( R rs 6 ) and reactance ( X rs 6 ) at 6 Hz, before and after inhalation of salbutamol 200 μg. Respiratory symptoms and/or medication use, asthma diagnosis, and smoking were recorded. Threshold bronchodilator responses were defined as the fifth percentile of decrease in R rs 6 and 95th percentile increase in X rs 6 in a healthy subgroup. Of 1318 participants, 1145 (570 female) were analysed. The lower threshold for Δ R rs 6 was −1.38 cmH 2 O·s·L −1 (−30.0% or −1.42 Z-scores) and upper threshold for Δ X rs 6 was 0.57 cmH 2 O·s·L −1 (1.36 Z-scores). Respiratory symptoms and/or medication use, asthma diagnosis, and smoking all predicted bronchodilator response, as did baseline oscillometry and spirometry. When categorised into clinically relevant groups according to those predictors, Δ X rs 6 was more sensitive than spirometry in smokers without current asthma or chronic obstructive pulmonary disease (COPD), ∼20% having a positive response. Using absolute or Z-score change provided similar prevalences of responsiveness, except in COPD, in which responsiveness measured by absolute change was twice that for Z-score. This study describes normative thresholds for bronchodilator responses in oscillometry parameters, including intra-breath parameters, as determined by absolute, relative and Z-score changes. Positive bronchodilator response by oscillometry correlated with clinical factors and baseline function, which may inform the clinical interpretation of oscillometry.
Publisher: Elsevier BV
Date: 12-2011
DOI: 10.1016/J.RMED.2011.07.010
Abstract: The mechanisms of airway hyper-responsiveness are only partially understood and the contribution of airway remodelling is unknown. Airway remodelling can be assessed by measuring airway distensibility, which is reduced in asthma, even when lung function is normal. We hypothesised that airway remodelling contributes to airway hyper-responsiveness in asthma, independent of steroid-responsive airway inflammation. To determine the relationship between airway distensibility and airway responsiveness at baseline and after 12 weeks of inhaled corticosteroid therapy in a group of asthmatics with airway hyper-responsiveness. Nineteen doctor-diagnosed asthmatics had airway distensibility measured as the slope of the relationship between conductance and lung volume by the forced oscillation technique. Lung function, exhaled nitric oxide and methacholine challenge were also measured. Subjects had inhaled corticosteroid therapy for 12 weeks after which all measurements were repeated. At baseline, airway distensibility (mean, 95%CI) was 0.19(0.14-0.23) cm H(2)O(-1)s(-1), exhaled nitric oxide was 13.1(10.3-16.6)ppb and airway distensibility correlated with eNO (p=0.04) and disease duration (p=0.02) but not with airway responsiveness (p=0.46), FEV(1) (p=0.09) or age (p=0.23). After treatment, exhaled nitric oxide decreased (p=0.0002), FEV(1) improved (p=0.0001), airway responsiveness improved (p=0.0002), and there was a small improvement in airway distensibility but it did not normalise (p=0.05). Airway distensibility was not correlated with either exhaled nitric oxide (p=0.49) or airway responsiveness (p=0.20). Uncontrolled airway inflammation causes a small decrease in the distensibility of the airways of asthmatics with airway hyper-responsiveness. The lack of association between airway responsiveness and airway distensibility, both before and after 12 weeks ICS treatment, suggests that airway remodelling does not contribute to airway hyper-responsiveness in asthma.
Publisher: Wiley
Date: 21-11-2022
Abstract: To describe the demographics, presentation characteristics, clinical features and cardiac outcomes for Aboriginal and Torres Strait Islander patients who present to a regional cardiac referral centre ED with suspected acute coronary syndrome (ACS). This was a single‐centre observational study conducted at a regional referral hospital in Far North Queensland, Australia from November 2017 to September 2018 and January 2019 to December 2019. Study participants were 278 Aboriginal and Torres Strait Islander people presenting to an ED and investigated for suspected ACS. The main outcome measure was the proportion of patients with ACS at index presentation and differences in characteristics between those with and without ACS. ACS at presentation was diagnosed in 38.1% of patients ( n = 106). The mean age of patients with ACS was 53.5 years (SD 9.5) compared with 48.7 years (SD 12.1) in those without ACS ( P = 0.001). Patients with ACS were more likely to be male (63.2% vs 39.0%, P 0.001), smokers (70.6% vs 52.3%, P = 0.002), have diabetes (56.6% vs 38.4%, P = 0.003) and have renal impairment (24.5% vs 10.5%, P = 0.002). Aboriginal and Torres Strait Islander patients with suspected ACS have a high burden of traditional cardiac risk factors, regardless of whether they are eventually diagnosed with ACS. These patients may benefit from assessment for coronary artery disease regardless of age at presentation.
Publisher: Wiley
Date: 27-10-2022
Abstract: To report the arrival ionised calcium (iCa) and fibrinogen concentrations in trauma patients treated with packed red blood cells by the road‐based high‐acuity response units of a metropolitan ambulance service. A retrospective review of trauma patients treated with packed red blood cells by high‐acuity response units between January 2012 and December 2016. Patients were identified from databases at southeast Queensland adult trauma centres, Pathology Queensland Central Transfusion Laboratory, Gold Coast University Hospital blood bank and the Queensland Ambulance Service. Patient characteristics, results of laboratory tests within 30 min of ED arrival were analysed. A total of 164 cases were analysed. The median injury severity score was 33.5 (interquartile range 22–41), with blunt trauma the commonest mechanism of injury ( n = 128, 78.0%). Fifty‐eight of the 117 patients (24.4%) with fibrinogen measured had a fibrinogen concentration ≤1.5 g/L 79 of the 123 patients (64.2%) with an international normalised ratio (INR) measurement had an INR .2 97 of 148 patients (63.8%) with an iCa measured, had an iCa below the Pathology Queensland reference range of 1.15–1.32 mmol/L. Arrival fibrinogen concentration ≤1.5 g/L and arrival iCa ≤1.00 were associated with in‐hospital mortality with odds ratio 11.90 (95% confidence interval 4.50–31.65) and odds ratio 4.97 (95% confidence interval 1.42–17.47), respectively. Hypocalcaemia and hypofibrinogenaemia on ED arrival were common in this cohort. Future work should evaluate whether outcomes improve by correction of these deficits during the pre‐hospital phase of trauma care.
Publisher: European Respiratory Society (ERS)
Date: 05-1996
DOI: 10.1183/09031936.96.09050910
Abstract: Nitrogen dioxide (NO2) is one of a number of nitrogen compounds that are by-products of combustion and occur in domestic environments following the use of gas or other fuels for heating and cooking. In this study, we examined the effect of two levels of NO2 on symptoms, lung function and airway hyperresponsiveness (AHR) in asthmatic adults and children. In addition, in the same subjects, we examined the effects of the same levels of NO2 mixed with combustion by-products from a gas space heater. The subjects were nine adults, aged 19-65 yrs, and 11 children, aged 7-15 yrs, with diagnosed asthma which was severe enough to require daily medication. All subjects had demonstrable AHR to histamine. Exposures were for 1 h on five separate occasions, 1 week apart, to: 1) ambient air, drawn from outside the building 2) 0.3 parts per million (ppm) NO2 in ambient air 3) 0.6 ppm NO2 in ambient air 4) ambient air+combustion by-products+NO2 to give a total of 0.3 ppm and 5) ambient air+combustion by-products+NO2 to give a total of 0.6 ppm. Effects were measured as changes in lung function and symptoms during and 1 h after exposure, in AHR 1 h and 1 week after exposure, and in lung function and symptoms during the week following exposure. Exposure to NO2 either in ambient air or mixed with combustion by-products from a gas heater, had no significant effect on symptoms or lung function in adults or in children. There was a small, but statistically significant, increase in AHR after exposure to 0.6 ppm NO2 in ambient air. However, there was no effect of 0.6 ppm NO2 on AHR when the combustion by-products were included in the test atmosphere nor of 0.3 ppm NO2 under either exposure condition. We conclude that a 1 h exposure to 0.3 or 0.6 ppm NO2 has no clinically important effect on the airways of asthmatic adults or children, but that 0.6 ppm may cause a slight increase in airway hyperresponsiveness.
Publisher: Cold Spring Harbor Laboratory
Date: 25-09-2023
Publisher: Wiley
Date: 08-11-2018
Abstract: Injuries are a major burden on the Australian healthcare system. Power tool usage is a common cause of accidental injury. A better understanding of the trends of power tool injuries will inform prevention strategies and potentially mitigate costs. The ED databases from two level 1 hospitals were reviewed for presentations between 2005 and 2015 resulting from accidental injury with power tools. A subgroup of patients presenting to one hospital between 2016 and 2017 were interviewed about the activities and circumstances that led to their injuries, and followed up 3 months later to assess outcomes. A total of 4057 cases of accidental injury from power tool use were identified. Power saws and grinders contributed to 54% of injuries. Most injuries were located on an upper limb (48%) or the head and neck (30%). Over half (54%) of all head injuries were associated with metal and wood fragments to the eye from grinders, drills and saws. Hospital admission rates were highest for patients aged >60 years. Injuries to females were 3 months were common. Accidental injuries from power tool use have a considerable impact on ED resources and can affect the long-term quality of life of those injured. Effective education about safe usage and protection may prevent many injuries.
Publisher: Wiley
Date: 12-07-2021
DOI: 10.1002/EMP2.12470
Abstract: The objective of this study was to determine if vehicle rollover in a motor vehicle crash is an independent predictor of major injury. A retrospective cohort study of all patients injured in motor vehicle crashes presenting to a major trauma center between July 2012 and June 2016 was conducted. Crashes were classified into groups: non‐rollover, isolated rollover (without other mechanisms of injury), or mixed‐mechanism rollover (with other mechanisms of injury). Associations between rollover group, other covariates (entrapment, encapsulation, ejection, death on scene, high speed, seat belt usage, airbag deployment, trauma team activation), and major injury (injury severity score , major surgery, intensive care unit admission, or in‐hospital death) were tested using binary logistic regression models. Vehicle rollover was categorized either as “present” or “absent” on 1 model or as either “none,” “isolated,” or “mixed mechanism” in the other. In 2446 motor vehicle crashes, there were 423 rollovers (196 isolated, 227 mixed mechanisms). Compared with crashes without rollovers, the prevalence of patients with major injury was lower in crashes with isolated rollovers and higher in crashes with mixed‐mechanism rollovers (13.8% vs 9.5% vs 27.5%, respectively P 0.001). Rollover (present vs absent) was not an independent predictor of major injury (odds ratio [OR], 1.10 95% confidence interval [CI], 0.78–1.53). Patients in crashes with mixed‐mechanism but not isolated rollovers had increased odds (OR, 2.04 95% CI, 1.41–2.96) of major injury compared with patients from crashes without rollovers. Patients from crashes with isolated vehicle rollovers may not need to be transported to a trauma center as they carry a lower risk of injury.
Publisher: Wiley
Date: 15-08-2023
Abstract: To determine the independent predictors for clinician fatigue and decline in cognitive function following a shift in the ED during early stages of the COVID‐19 pandemic. This was a prospective, quasi‐experimental study conducted in a metropolitan adult tertiary‐referral hospital ED over 20 weeks in 2021. The participants were ED doctors and nurses working clinical shifts in an ED isolation area or high‐risk zone (HRZ) with stringent personal protective equipment (PPE). The participants' objective and subjective fatigue was measured by the Samn–Perelli fatigue score and a psychomotor vigilance ‘smart game’ score, respectively. Postural signs/symptoms and urine specific gravity (SG) were measured as markers of dehydration. Sixty‐three participants provided data for 263 shifts. Median (interquartile range) age was 33 (28–38) years, 73% were female. Worsening fatigue score was associated with working afternoon shifts (afternoon vs day, adjusted odds ratio [aOR] 5.16 [95% confidence interval (CI) 1.32–20.02]) and in non‐HRZ locations (HRZ vs non‐HRZ, aOR 0.23 [95% CI 0.06–0.87]). Worsening cognitive function (game score) was associated with new onset postural symptoms (new vs no symptoms, aOR 4.14 [95% CI 1.34–12.51]) and afternoon shifts (afternoon vs day, aOR 3.13 [95% CI 1.16–8.44]). Working in the HRZ was not associated with declining cognitive function. Thirty‐four (37%) of the 92 participants had an end of shift urine SG .030. Working afternoon shifts was associated with fatigue. There was no association between HRZ allocation and fatigue, but our study was limited by a low COVID workload and fluctuating PPE requirements in the non‐HRZs. Workplace interventions that target the prevention of fatigue in ED clinicians working afternoon shifts should be prioritised.
Publisher: Elsevier BV
Date: 10-2009
DOI: 10.1016/J.PUPT.2009.04.008
Abstract: Stress and strain are omnipresent in the lung due to constant lung volume fluctuation associated with respiration, and they modulate the phenotype and function of all cells residing in the airways including the airway smooth muscle (ASM) cell. There is le evidence that the ASM cell is very sensitive to its physical environment, and can alter its structure and/or function accordingly, resulting in either desired or undesired consequences. The forces that are either conferred to the ASM cell due to external stretching or generated inside the cell must be borne and transmitted inside the cytoskeleton (CSK). Thus, maintaining appropriate levels of stress and strain within the CSK is essential for maintaining normal function. Despite the importance, the mechanisms regulating/dysregulating ASM cytoskeletal filaments in response to stress and strain remained poorly understood until only recently. For ex le, it is now understood that ASM length and force are dynamically regulated, and both can adapt over a wide range of length, rendering ASM one of the most malleable living tissues. The malleability reflects the CSK's dynamic mechanical properties and plasticity, both of which strongly interact with the loading on the CSK, and all together ultimately determines airway narrowing in pathology. Here we review the latest advances in our understanding of stress and strain in ASM cells, including the organization of contractile and cytoskeletal filaments, range and adaptation of functional length, structural and functional changes of the cell in response to mechanical perturbation, ASM tone as a mediator of strain-induced responses, and the novel glassy dynamic behaviors of the CSK in relation to asthma pathophysiology.
Publisher: Elsevier BV
Date: 06-2011
Abstract: Age-related increases in morbidity and mortality due to asthma may be due to changes in pathophysiology as patients with asthma get older. There is limited knowledge about the effects of age on the predictors of airway hyperresponsiveness (AHR), a key feature of asthma. The aim of this study was to determine if the pathophysiologic predictors of AHR, including inflammation, ventilation heterogeneity, and airway closure, differed between young and old patients with asthma. Sixty-one young (18-46 years) and 43 old (50-80 years) patients with asthma had lung function, lung volumes, fraction of exhaled nitric oxide, ventilation heterogeneity, and airway responsiveness to methacholine measured. Airway response to methacholine was measured by the dose-response slope, as the percent fall in FEV(1) per micromole of methacholine. Indices of ventilation heterogeneity were calculated for convection-dependent and diffusion-dependent airways. In young patients with asthma, the independent predictors of AHR were convection-dependent ventilation heterogeneity, exhaled nitric oxide, and % predicted FEV(1)/FVC (model r(2) = 0.51, P < .0001). In old patients with asthma, the independent predictors of airway responsiveness were % predicted residual volume, diffusion-dependent ventilation heterogeneity, and % predicted FEV(1) (model r(2) = 0.57, P < .0001). In old patients with asthma, AHR is predicted by gas trapping and ventilation heterogeneity in peripheral, diffusion-dependent airways. In the young, it is predicted by ventilation heterogeneity in less peripheral conducting airways and by inflammation. These findings suggest that there are differences in the pathophysiologic determinants of AHR between young and old patients with asthma.
Publisher: Wiley
Date: 05-03-2019
Abstract: To compare the documentation of security interventions in ED presentations between clinical notes and security records. Presentations (n = 680) were randomly selected from all ED presentations to a public tertiary referral hospital in Queensland, Australia between April 2016 and August 2017 that were perceived by the treating clinician as alcohol-related. Retrospective data, manually extracted from clinical notes and the security service database, were compared for the documentation of any security interventions. Security interventions were defined as observation without physical contact, verbal de-escalation or physical restraint by security officers. Forty-one presentations had security interventions documented in the security services database and, of those, 20 (48.8%) had documentation in the clinical notes. Patients who required security interventions were admitted to hospital in higher proportions compared with those who did not (73.2% vs 26.8%, respectively, P < 0.0001). The rate of documentation of security interventions in clinical notes was less than 50%. Documentation of critical information, including alerts and risks, in the clinical notes is an essential component of communication that the multi-disciplinary team use to ensure patient safety. Strategies aimed at improving the documentation of security interventions in clinical notes will help to optimise risk management and the safety of patients, staff and visitors along the continuum of care.
Publisher: Springer Science and Business Media LLC
Date: 09-03-2010
DOI: 10.1007/S11517-010-0576-3
Abstract: In order to understand the pathophysiology of diseases such as asthma and chronic obstructive pulmonary disease, it is essential to measure the mechanical properties of the airways. Currently, there are no methods to measure and quantify in vivo airway compliance in humans. In order to develop a method, we generated a curve-fitting algorithm that combines airway diameter measurements by high resolution computed tomography with pressure-volume curves obtained by the esophageal balloon technique. Our method allows the description of diameter-pressure curves for airways of varying size, presented as a 3D surface, from which specific airway compliance can be determined at any transpulmonary pressure. Applying this method to data from two healthy subjects, we found that small airways are more compliant than large airways and specific airway compliance was greatest at low transpulmonary pressures. In conclusion, our 3D surface is a useful tool to measure and quantify in vivo specific airway compliance in humans.
Start Date: 2010
End Date: 2013
Funder: National Health and Medical Research Council
View Funded ActivityStart Date: 2018
End Date: 2019
Funder: Royal Brisbane and Women's Hospital Foundation
View Funded ActivityStart Date: 2018
End Date: 2019
Funder: Emergency Medicine Foundation
View Funded ActivityStart Date: 2008
End Date: 2011
Funder: National Health and Medical Research Council
View Funded ActivityStart Date: 2020
End Date: 2022
Funder: Emergency Medicine Foundation
View Funded Activity