ORCID Profile
0000-0003-4209-0334
Current Organisations
Auckland District Health Board
,
Monash University
,
The University of Auckland
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Publisher: Wiley
Date: 17-06-2019
DOI: 10.1111/JAN.13994
Abstract: To assess the safety and efficacy of avoiding endotracheal suction in postoperative cardiac surgical patients mechanically ventilated for ≤ 12 hr. A prospective, single centre, single blind, non-inferiority, randomized controlled trial evaluating the safety and efficacy of avoiding suction in uncomplicated, postoperative, adult cardiac surgical patients mechanically ventilated for ≤ 12 hr. Randomization will be performed on return to intensive care (ICU) with allocation to either usual postoperative care including suction or to usual care with no suction (intervention arm). The primary outcome is the ratio of partial pressure of oxygen (PaO Endotracheal suction is performed as part of airway management but has potential complications and there is little robust evidence to guide practice. This study will add to the evidence base about the need and benefit of endotracheal suction in this patient cohort. As there is currently no published evidence about the safety of avoiding endotracheal suction. This study will provide the first evidence about avoidance of endotracheal suction in patients ventilated for less than 1 day. If non-inferior, the results have the capacity to change nursing practice by avoiding a potentially unnecessary procedure, it will build on the body of knowledge about the patient experience.
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1093/BJA/AEV118
Abstract: After cardiac surgery, patients receive large amounts of fluid in the Intensive Care Unit (ICU). We plan to conduct a multi-centre randomised controlled trial, of a conservative fluid regime, in patients after cardiac surgery, and have reported results of a feasibility study that evaluated efficacy and safety of the proposed regime. After ethical approval, a single-centre, prospectively randomised interventional study was undertaken. Participants were randomised to either usual care, or to a protocolised algorithm, utilising stroke volume variation, to guide fluid administration to patients who were deemed to have inadequate cardiac output and were likely to be volume responsive. The study protocol lasted from ICU admission to de-sedation or 24 h, whichever occurred first. We randomised 144 subjects over 9 months. Less bolus fluid and less total overall fluid volume was administered in the intervention group (median (IQR) 1620 ml (500-3410) and 2525 ml (1440-5250 P<0.001), compared with the usual care group (2050 ml (910-4280) and 2980 ml (2070-6580 P=0.001), from ICU admission to extubation. There was no significant difference in incidence of acute kidney injury or the average amount of fluid administered to the usual care group at the beginning compared with the end of the study. It is both possible and safe to achieve a significant reduction in the amount of fluid administered to patients, allocated to a conservative fluid protocol. These results suggest that a planned multi-centre study is both justified and feasible. Australia New Zealand Clinical Trials Registry www.anzctr.org.au (ACTRN12612000754842).
Publisher: Elsevier BV
Date: 03-2012
DOI: 10.1016/J.IJNURSTU.2011.09.011
Abstract: Postoperative respiratory complications following cardiac surgery may increase morbidity, mortality and length of stay. Non-invasive respiratory support therapies can be used prophylactically or curatively to reduce respiratory complications. One system, nasal high flow oxygen therapy, is in use in many intensive care units (ICUs) however there is a lack of information regarding its clinical utility and efficacy. This paper outlines the study protocol and methodology for a study designed to determine if the prophylactic use of nasal high flow oxygen therapy can improve pulmonary function in patients following cardiac surgery. A prospective randomised controlled trial will be conducted of adult patients scheduled for cardiac surgery and admitted to the Cardiothoracic Intensive Care Unit of a tertiary hospital. Study participants will be assigned to receive either nasal high flow or standard oxygen therapy (oxygen therapy at 2-4 L/min via either simple facemask or nasal cannulae) at extubation. The primary outcome measure is improved pulmonary function demonstrated by SpO2/FiO2 ratio >445 on post-operative day 3. Secondary outcome measures include atelectasis score on chest X-ray spirometry readmission to ICU for respiratory causes ICU and hospital length of stay mortality and incidence of respiratory complications at day 28 oxygenation variables use of adjunctive respiratory support therapies escalation of respiratory support adverse events and patient comfort during administration of oxygen therapy. It was calculated that 340 patients will be required--170 per arm of study--to give a 90% power to detect a 15% treatment effect. This study started recruiting in March 2011. It is anticipated that enrollment will be complete in April 2012 and results available towards the end of 2012. This study will provide evidence of any benefits in the use of prophylactic nasal high flow therapy in post-operative cardiac surgical patients. This trial is registered with the Australian New Zealand Clinical Trials Registry www.anzctr.org.au (ACTRN12610000973011).
Publisher: Daedalus Enterprises
Date: 03-2011
Abstract: In a cardiothoracic and vascular intensive care unit, to compare nasal high-flow (NHF) oxygen therapy and standard high-flow face mask (HFFM) oxygen therapy in patients with mild to moderate hypoxemic respiratory failure. In a prospective randomized comparative study, 60 patients with mild to moderate hypoxemic respiratory failure were randomized to receive NHF or HFFM. We analyzed the success of allocated therapy, noninvasive ventilation rate, and oxygenation. Significantly more NHF patients succeeded with their allocated therapy (P = .006). The rate of noninvasive ventilation in the NHF group was 3/29 (10%), compared with 8/27 (30%) in the HFFM group (P = .10). The NHF patients also had significantly fewer desaturations (P = .009). NHF oxygen therapy may be more effective than HFFM in treating mild to moderate hypoxemic respiratory failure.
Publisher: JMIR Publications Inc.
Date: 27-01-2022
Abstract: he LOVIT (Lessening Organ Dysfunction with Vitamin C) trial is a blinded multicenter randomized clinical trial comparing high-dose intravenous vitamin C to placebo in patients admitted to the intensive care unit with proven or suspected infection as the main diagnosis and receiving a vasopressor. e aim to describe a prespecified statistical analysis plan (SAP) for the LOVIT trial prior to unblinding and locking of the trial database. he SAP was designed by the LOVIT principal investigators and statisticians, and approved by the steering committee and coinvestigators. The SAP defines the primary and secondary outcomes, and describes the planned primary, secondary, and subgroup analyses. he SAP includes a draft participant flow diagram, tables, and planned figures. The primary outcome is a composite of mortality and persistent organ dysfunction (receipt of mechanical ventilation, vasopressors, or new renal replacement therapy) at 28 days, where day 1 is the day of randomization. All analyses will use a frequentist statistical framework. The analysis of the primary outcome will estimate the risk ratio and 95% CI in a generalized linear mixed model with binomial distribution and log link, with site as a random effect. We will perform a secondary analysis adjusting for prespecified baseline clinical variables. Subgroup analyses will include age, sex, frailty, severity of illness, Sepsis-3 definition of septic shock, baseline ascorbic acid level, and COVID-19 status. e have developed an SAP for the LOVIT trial and will adhere to it in the analysis phase. ERR1-10.2196/36261
Publisher: American Thoracic Society
Date: 07-2020
Publisher: Wiley
Date: 20-06-2019
DOI: 10.1002/JPEN.1196
Abstract: Little is currently known about nutrition intake and energy requirements in the post-intensive care unit (ICU) hospitalization period in critically ill patients. We aimed to describe energy and protein intake, and determine the feasibility of measuring energy expenditure during the post-ICU hospitalization period in critically ill adults. This is a nested cohort study within a randomized controlled trial in critically ill patients. After discharge from ICU, energy and protein intake was quantified periodically and indirect calorimetry attempted. Data are presented as n (%), mean (SD), and median (interquartile range [IQR]). Thirty-two patients were studied in the post-ICU hospitalization period, and 12 had indirect calorimetry. Mean age and BMI was 56 (18) years and 30 (8) kg/m Energy and protein intake in the post-ICU hospitalization period was less than estimated and measured energy requirements. Oral nutrition provided alone was the most common mode of nutrition therapy.
Publisher: Daedalus Enterprises
Date: 09-2015
Abstract: Previous research has demonstrated a positive linear correlation between flow delivered and airway pressure generated by high-flow nasal therapy. Current practice is to use flows over a range of 30-60 L/min however, it is technically possible to apply higher flows. In this study, airway pressure measurements and electrical impedance tomography were used to assess the relationship between flows of up to 100 L/min and changes in lung physiology. Fifteen healthy volunteers were enrolled into this study. A high-flow nasal system capable of delivering a flow of 100 L/min was purpose-built using 2 Optiflow systems. Airway pressure was measured via the nasopharynx, and cumulative changes in end-expiratory lung impedance were recorded using the PulmoVista 500 system at gas flows of 30-100 L/min in increments of 10 L/min. The mean age of study participants was 31 (range 22-44) y, the mean ± SD height was 171.8 ± 7.5 cm, the mean ± SD weight was 69.7 ± 10 kg, and 47% were males. Flows ranged from 30 to 100 L/min with resulting mean ± SD airway pressures of 2.7 ± 0.7 to 11.9 ± 2.7 cm H2O. A cumulative and linear increase in end-expiratory lung impedance was observed with increasing flows, as well as a decrease in breathing frequency. Measured airway pressure and lung impedance increased linearly with increased gas flow. Observed airway pressures were in the range used clinically with face-mask noninvasive ventilation. Developments in delivery systems may result in this therapy being an acceptable alternative to face-mask noninvasive ventilation.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2013
Publisher: Elsevier BV
Date: 2016
DOI: 10.1053/J.JVCA.2015.07.034
Abstract: Neutrophil gelatinase-associated lipocalin (NGAL) appears to be a promising biomarker in the effort to predict acute kidney injury (AKI) after cardiac surgery. The authors aimed to identify the specific time point in the perioperative period at which measurement of either urinary or serum concentrations of NGAL would have the highest predictive power for AKI. The authors also investigated whether change in NGAL from baseline was a better predictor of AKI than absolute NGAL values. A prospective, investigator-blinded observational study. The cardiac surgical unit of a university teaching hospital. The study consisted of 50 patients undergoing cardiac surgery who were classified preoperatively as high risk for developing postoperative AKI. No changes to standard practice were required. The authors performed serial measurements of urinary and serum NGAL concentrations at 18 time points throughout the first 48 postoperative hours and assessed the variables required to diagnose AKI with standard criteria. Statistical analysis of predictive ability was performed using the area under receiver operator curves (AUROC) calculated for each time point. It was demonstrated that urinary NGAL performed marginally better than serum NGAL in predicting AKI. Urinary s ling at 4 and 24 hours after initiation of cardiopulmonary bypass provided the greatest diagnostic ability (AUROC, 0.702 and 0.712, respectively). Absolute NGAL values performed better than changes in NGAL values in predicting AKI. Urinary NGAL performed better than serum NGAL in predicting AKI and was most accurate when measured at 24 hours after initiation of cardiopulmonary bypass however, NGAL appeared to be at best only a fair predictor of cardiac surgery-associated AKI.
Publisher: Elsevier BV
Date: 07-2016
DOI: 10.1093/BJA/AEW162
Publisher: Daedalus Enterprises
Date: 19-03-2013
Abstract: Nasal high flow (NHF) oxygen therapy and CPAP are modes of noninvasive respiratory support used to improve respiratory function in multiple patient groups. Both therapies provide positive pressure, although this varies during the respiratory cycle. The purpose of this study was to measure and compare the airway pressure generated during different phases of the respiratory cycle in patients receiving NHF at various gas flows. Patients scheduled for elective cardiac surgery were invited to participate. Nasopharyngeal pressure measurements were performed using NHF with gas flows of 30, 40, and 50 L/min. All measurements were performed in random order, with the subject breathing with mouth closed. During NHF the mean ± SD nasopharyngeal airway pressures were 1.5 ± 0.6, 2.2 ± 0.8, and 3.1 ± 1.2 at 30, 40, and 50 L/min using NHF. Analyses also determined the mean peak expiratory and mean expiratory plateau pressures. The expiratory pressure during NHF was higher than the mean pressure previously reported for NHF. This may account in part for the disproportional clinical effects seen with NHF. (Australian Clinical Trials Registry www.anzctr.org.au ACTRN12609000305224).
Publisher: Daedalus Enterprises
Date: 08-2011
Abstract: Nasal high-flow oxygen therapy increases the mean nasopharyngeal airway pressure in adults, but the relationship between flow and pressure is not well defined. To determine the relationship between flow and pressure with the Optiflow nasal high-flow oxygen therapy system. We invited patients scheduled for elective cardiac surgery to participate. Measurements were performed with nasal high-flow oxygen at flows of 30, 40, and 50 L/min, with the patient's mouth both open and closed. Pressures were recorded over one minute of breathing, and average flows were calculated via simple averaging. With the mouth closed, the mean ± SD airway pressures at 30, 40, and 50 L/min were 1.93 ± 1.25 cm H(2)O, 2.58 ± 1.54 cm H(2)O, and 3.31 ± 1.05 cm H(2)O, respectively. There was a positive linear relationship between flow and pressure. The mean nasopharyngeal pressure during nasal high-flow oxygen increases as flow increases. Australian Clinical Trials Registry www.adhb.govt.nz/achicu/hot_2_airway_pressure.htm.
Publisher: Elsevier BV
Date: 03-2019
DOI: 10.1016/J.AUCC.2018.03.001
Abstract: Despite the evidence and available guidelines about endotracheal suction (ETS), a discrepancy between published guidelines and clinical practice persists. To date, ETS practice in the adult intensive care unit (ICU) population across New Zealand and Australia has not been described. To describe ICU nurses' ETS practice in New Zealand and Australia including the triggers for performing endotracheal suction. A single day, prospective observational, binational, multicentre point prevalence study in New Zealand and Australian ICUs. All adult patients admitted at 10:00 on the study day were included. In addition to patient demographic data, we assessed triggers for ETS, suction canister pressures, use of preoxygenation, measures of oxygenation, and ETS at extubation. There were 682 patients in the ICUs on the study day, and 230 were included in the study. Three of 230 patients were excluded for missing data. A total of 1891 ETS events were performed on 227 patients during the study day, a mean of eight interventions per patient. The main triggers reported were audible (n = 385, 63%) and visible (n = 239, 39%) secretions. Less frequent triggers included following auscultation (n = 142, 23%), reduced oxygen saturations (n = 140, 22%), and ventilator waveforms (n = 53, 9%). Mean suction canister pressure was -337 mmHg (standard deviation = 189), 67% of patients received preoxygenation (n = 413), and ETS at extubation was performed by 84% of nurses. Some practices were inconsistent with international guidelines, in particular concerning patient assessment for ETS and suction canister pressure.
Publisher: Elsevier BV
Date: 08-2023
Publisher: BMJ
Date: 14-02-2023
DOI: 10.1136/BMJQS-2022-015471
Abstract: Visiting restrictions were enacted in Aotearoa New Zealand to reduce transmission of COVID-19 and protect the healthcare system. This research aimed to investigate the experiences of families and clinicians of hospital visiting for people with palliative and end-of-life care needs during restrictions. Semistructured interviews were completed between March and October 2021 with family members and clinicians who had personally experienced enactment of visiting restrictions during pandemic restrictions. A critical realist ontology was used to approach data analysis, sorting and coding to generate themes. Twenty-seven participants were interviewed, 13 being families who had experienced bereavement of a family member during the restrictions: seven nurses or physicians and seven being non-bereaved family members. Four themes were generated: patient safety—(re)defining the ‘Visitor’ the primacy of SARS-CoV-2—patient safety and negotiating risk dying alone: enduring harms and agency, strategies and workarounds. Visitor rights and visitor policy at the end of life require greater protection during a pandemic. Transparent, coherent, publicly available evidence-based guidelines that key stakeholders, including patients, families and ethicists, are included in producing, are urgently required. We want to avert a legacy of disenfranchised grief in future pandemics.
Publisher: JMIR Publications Inc.
Date: 20-05-2022
DOI: 10.2196/36261
Abstract: The LOVIT (Lessening Organ Dysfunction with Vitamin C) trial is a blinded multicenter randomized clinical trial comparing high-dose intravenous vitamin C to placebo in patients admitted to the intensive care unit with proven or suspected infection as the main diagnosis and receiving a vasopressor. We aim to describe a prespecified statistical analysis plan (SAP) for the LOVIT trial prior to unblinding and locking of the trial database. The SAP was designed by the LOVIT principal investigators and statisticians, and approved by the steering committee and coinvestigators. The SAP defines the primary and secondary outcomes, and describes the planned primary, secondary, and subgroup analyses. The SAP includes a draft participant flow diagram, tables, and planned figures. The primary outcome is a composite of mortality and persistent organ dysfunction (receipt of mechanical ventilation, vasopressors, or new renal replacement therapy) at 28 days, where day 1 is the day of randomization. All analyses will use a frequentist statistical framework. The analysis of the primary outcome will estimate the risk ratio and 95% CI in a generalized linear mixed model with binomial distribution and log link, with site as a random effect. We will perform a secondary analysis adjusting for prespecified baseline clinical variables. Subgroup analyses will include age, sex, frailty, severity of illness, Sepsis-3 definition of septic shock, baseline ascorbic acid level, and COVID-19 status. We have developed an SAP for the LOVIT trial and will adhere to it in the analysis phase. DERR1-10.2196/36261
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2016
DOI: 10.1097/CCM.0000000000001643
Abstract: To determine if the early goal-directed mobilization intervention could be delivered to patients receiving mechanical ventilation with increased maximal levels of activity compared with standard care. A pilot randomized controlled trial. Five ICUs in Australia and New Zealand. Fifty critically ill adults mechanically ventilated for greater than 24 hours. Patients were randomly assigned to either early goal-directed mobilization (intervention) or to standard care (control). Early goal-directed mobilization comprised functional rehabilitation treatment conducted at the highest level of activity possible for that patient assessed by the ICU mobility scale while receiving mechanical ventilation. The ICU mobility scale, strength, ventilation duration, ICU and hospital length of stay, and total inpatient (acute and rehabilitation) stay as well as 6-month post-ICU discharge health-related quality of life, activities of daily living, and anxiety and depression were recorded. The mean age was 61 years and 60% were men. The highest level of activity (ICU mobility scale) recorded during the ICU stay between the intervention and control groups was mean (95% CI) 7.3 (6.3–8.3) versus 5.9 (4.9–6.9), p = 0.05. The proportion of patients who walked in ICU was almost doubled with early goal-directed mobilization (intervention n = 19 [66%] vs control n = 8 [38%] p = 0.05). There was no difference in total inpatient stay (d) between the intervention versus control groups (20 [15–35] vs 34 [18–43] p = 0.37). There were no adverse events. Key Practice Points: Delivery of early goal-directed mobilization within a randomized controlled trial was feasible, safe and resulted in increased duration and level of active exercises.
No related grants have been discovered for Rachael Parke.