Protocol summary and statistical analysis plan for the low oxygen intervention for cardiac arrest injury limitation (LOGICAL) trial

Background

The effect of conservative vs. liberal oxygen therapy on outcomes of intensive care unit (ICU) patients with hypoxic ischaemic encephalopathy (HIE) is uncertain and will be evaluated in the Low Oxygen Intervention for Cardiac Arrest injury Limitation (LOGICAL) trial.

Objective

The objective of this study was to summarise the protocol and statistical analysis plans for the LOGICAL trial.

Design setting and participants

LOGICAL is a randomised clinical trial in adults in the ICU who are comatose with suspected HIE (i.e., those who have not obeyed commands following return of spontaneous circulation after a cardiac arrest where there is clinical concern about possible brain damage). The LOGICAL trial will include 1400 participants and is being conducted as a substudy of the Mega Randomised registry trial comparing conservative vs. liberal oxygenation targets in adults receiving unplanned invasive mechanical ventilation in the ICU (Mega-ROX).

Main outcome measures

The primary outcome is survival with favourable neurological function at 180 days after randomisation as measured with the Extended Glasgow Outcome Scale (GOS-E). A favourable neurological outcome will be defined as a GOS-E score of lower moderate disability or better (i.e. a GOS-E score of 5-8). Secondary outcomes include survival time, day 180 mortality, duration of invasive mechanical ventilation, ICU length of stay, hospital length of stay, the proportion of patients discharged home, quality of life assessed at day 180 using the EQ-5D-5L, and cognitive function assessed at day 180 using the Montreal Cognitive Assessment (MoCA-blind).

Conclusions

The LOGICAL trial will provide reliable data on the impact of conservative vs. liberal oxygen therapy in ICU patients with suspected HIE following resuscitation from a cardiac arrest. Prepublication of the LOGICAL protocol and statistical analysis plan prior to trial conclusion will reduce the potential for outcome-reporting or analysis bias.

Trial registration

Australian and New Zealand Clinical Trials Registry (ACTRN12621000518864).

Nursing workforce, education, and training challenges to implementing extracorporeal membrane oxygenation services in Australian intensive care units: A qualitative substudy

BACKGROUND

The use of extracorporeal membrane oxygenation (ECMO) is increasing in the management of critical care patients. ECMO service delivery requires an organisation-supported approach to ensure appropriate resources to deliver training, equipment, capacity, staffing, and the required model of care for quality care delivery. The aim of this nested substudy was to explore challenges specific to nursing staff in ECMO services in Australian intensive care units.

METHODS

This was a nested substudy within a qualitative study using semistructured focus group discussions conducted with 83 health professionals, which included 40 nurses. There were 14 focus groups across 14 ECMO centres participating in the binational ECMO (EXCEL) registry of Australia and New Zealand. An inductive thematic analysis focused on the nurse's experiences of the barriers and facilitators for nursing in providing an ECMO service.

RESULTS

Four themes emerged relating to the nurse's experience of implementing ECMO services: workforce requirements, workload demands, models of care, and level of experience. The complexity and intensity of caring for ECMO patients may need to be considered an additional factor in the burnout in critical care nurses. Current nursing ratios and responsibilities in critical care need to be considered, with the opportunity for the development of specialist advanced practitioner nursing roles.

CONCLUSION

This study highlights the challenges for nursing in providing ECMO services in the intensive care setting. The complexity and intensity of ECMO is challenging and leads to concerns regarding burnout and workforce preparedness. New models of care need to be considered to mitigate the barriers for nursing identified across ECMO centres.

Incidence of death or disability at 6 months after extracorporeal membrane oxygenation in Australia: a prospective, multicentre, registry-embedded cohort study

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is an invasive procedure used to support critically ill patients with the most severe forms of cardiac or respiratory failure in the short term, but long-term effects on incidence of death and disability are unknown. We aimed to assess incidence of death or disability associated with ECMO up to 6 months (180 days) after treatment.

METHODS

This prospective, multicentre, registry-embedded cohort study was done at 23 hospitals in Australia from Feb 15, 2019, to Dec 31, 2020. The EXCEL registry included all adults (≥18 years) in Australia who were admitted to an intensive care unit (ICU) in a participating centre at the time of the study and who underwent ECMO. All patients who received ECMO support for respiratory failure, cardiac failure, or cardiac arrest during their ICU stay were eligible for this study. The primary outcome was death or moderate-to-severe disability (defined using the WHO Disability Assessment Schedule 2.0, 12-item survey) at 6 months after ECMO initiation. We used Fisher's exact test to compare categorical variables. This study is registered with ClinicalTrials.gov, NCT03793257.

FINDINGS

Outcome data were available for 391 (88%) of 442 enrolled patients. The primary outcome of death or moderate-to-severe disability at 6 months was reported in 260 (66%) of 391 patients: 136 (67%) of 202 who received veno-arterial (VA)-ECMO, 60 (54%) of 111 who received veno-venous (VV)-ECMO, and 64 (82%) of 78 who received extracorporeal cardiopulmonary resuscitation (eCPR). After adjustment for age, comorbidities, Acute Physiology and Chronic Health Evaluation (APACHE) IV score, days between ICU admission and ECMO start, and use of vasopressors before ECMO, death or moderate-to-severe disability was higher in patients who received eCPR than in those who received VV-ECMO (VV-ECMO vs eCPR: risk difference [RD] -32% [95% CI -49 to -15]; p<0·001) but not VA-ECMO (VA-ECMO vs eCPR -8% [-22 to 6]; p=0·27).

INTERPRETATION

In our study, only a third of patients were alive without moderate-to-severe disability at 6 months after initiation of ECMO. The finding that disability was common across all areas of functioning points to the need for long-term, multidisciplinary care and support for surviving patients who have had ECMO. Further studies are needed to understand the 180-day and longer-term prognosis of patients with different diagnoses receiving different modes of ECMO, which could have important implications for the selection of patients for ECMO and management strategies in the ICU.

FUNDING

The National Health and Medical Research Council of Australia.

Comparison of 6-Month Outcomes of Survivors of COVID-19 versus Non-COVID-19 Critical Illness

Rationale: The outcomes of survivors of critical illness due to coronavirus disease (COVID-19) compared with non-COVID-19 are yet to be established. Objectives: We aimed to investigate new disability at 6 months in mechanically ventilated patients admitted to Australian ICUs with COVID-19 compared with non-COVID-19. Methods: We included critically ill patients with COVID-19 and non-COVID-19 from two prospective observational studies. Patients were eligible if they were adult (age ⩾ 8 yr) and received ⩾24 hours of mechanical ventilation. In addition, patients with COVID-19 were eligible with a positive laboratory PCR test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Measurements and Main Results: Demographic, intervention, and hospital outcome data were obtained from electronic medical records. Survivors were contacted by telephone for functional outcomes with trained outcome assessors using the World Health Organization Disability Assessment Schedule 2.0. Between March 6, 2020, and April 21, 2021, 120 critically ill patients with COVID-19, and between August 2017 and January 2019, 199 critically ill patients without COVID-19, fulfilled the inclusion criteria. Patients with COVID-19 were older (median [interquartile range], 62 [55-71] vs. 58 [44-69] yr; P = 0.019) with a lower Acute Physiology and Chronic Health Evaluation II score (17 [13-20] vs. 19 [15-23]; P = 0.011). Although duration of ventilation was longer in patients with COVID-19 than in those without COVID-19 (12 [5-19] vs. 4.8 [2.3-8.8] d; P < 0.001), 180-day mortality was similar between the groups (39/120 [32.5%] vs. 70/199 [35.2%]; P = 0.715). The incidence of death or new disability at 180 days was similar (58/93 [62.4%] vs. 99/150 [66/0%]; P = 0.583). Conclusions: At 6 months, there was no difference in new disability for patients requiring mechanical ventilation for acute respiratory failure due to COVID-19 compared with non-COVID-19. Clinical trial registered with www.clinicaltrials.gov (NCT04401254).

The impact of COVID-19 critical illness on new disability, functional outcomes and return to work at 6 months: a prospective cohort study

BACKGROUND

There are few reports of new functional impairment following critical illness from COVID-19. We aimed to describe the incidence of death or new disability, functional impairment and changes in health-related quality of life of patients after COVID-19 critical illness at 6 months.

METHODS

In a nationally representative, multicenter, prospective cohort study of COVID-19 critical illness, we determined the prevalence of death or new disability at 6 months, the primary outcome. We measured mortality, new disability and return to work with changes in the World Health Organization Disability Assessment Schedule 2.0 12L (WHODAS) and health status with the EQ5D-5LTM.

RESULTS

Of 274 eligible patients, 212 were enrolled from 30 hospitals. The median age was 61 (51-70) years, and 124 (58.5%) patients were male. At 6 months, 43/160 (26.9%) patients died and 42/108 (38.9%) responding survivors reported new disability. Compared to pre-illness, the WHODAS percentage score worsened (mean difference (MD), 10.40% [95% CI 7.06-13.77]; p < 0.001). Thirteen (11.4%) survivors had not returned to work due to poor health. There was a decrease in the EQ-5D-5LTM utility score (MD, - 0.19 [- 0.28 to - 0.10]; p < 0.001). At 6 months, 82 of 115 (71.3%) patients reported persistent symptoms. The independent predictors of death or new disability were higher severity of illness and increased frailty.

CONCLUSIONS

At six months after COVID-19 critical illness, death and new disability was substantial. Over a third of survivors had new disability, which was widespread across all areas of functioning. Clinical trial registration NCT04401254 May 26, 2020.

A survey of extracorporeal membrane oxygenation practice in 23 Australian adult intensive care units

In Australia, extracorporeal membrane oxygenation (ECMO) is one of the most expensive diagnosis-related groups, costing $305 463 per complex admission to the intensive care unit(ICU). Mortality in this group of patients is high, about 43% for respiratory failure and 68% for cardiac failure. ECMO is associated with significant risk to the patient and requires specialist training andexpertise. Variation in clinical practice for patients supported with ECMO may compromise patient care and outcomes.

Protocol summary and statistical analysis plan for the intensive care unit randomised trial comparing two approaches to oxygen therapy (ICU-ROX)

BACKGROUND

The balance of risks and benefits of conservative v standard care oxygen strategies for patients who are invasively ventilated in the intensive care unit (ICU) is uncertain.

OBJECTIVE

To describe the study protocol and statistical analysis plan for the ICU randomised trial comparing two approaches to oxygen therapy (ICU-ROX).

DESIGN, SETTING AND PARTICIPANTS

Protocol for a multicentre, randomised, participant and outcome assessor-blinded, standard care-controlled, parallel-group, two-sided superiority trial to be conducted in up to 22 ICUs in Australia and New Zealand. 1000 adults who are mechanically ventilated in the ICU and expected to remain ventilated beyond the day after recruitment will be randomly assigned to conservative oxygen therapy or standard care in a 1:1 ratio. ICU-ROX began with an internal pilot phase in September 2015. It is anticipated that recruitment will be completed in 2018.

MAIN OUTCOME MEASURES

The primary endpoint will be alive, ventilator-free days to Day 28. Secondary outcomes include 90- and 180-day all-cause mortality, survival time to 180 days, and quality of life and cognitive function at 180 days. All analyses will be conducted on an intentionto- treat basis.

RESULTS AND CONCLUSIONS

ICU-ROX will compare the effect of conservative v standard oxygen therapy in critically ill mechanically ventilated adults who are expected to be ventilated beyond the day after recruitment on ventilatorfree days to Day 28.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry (ANZCTRN 12615000957594).

Intensive care unit randomised trial comparing two approaches to oxygen therapy (ICU-ROX): results of the pilot phase

OBJECTIVE

The objective of the intensive care unit randomised trial comparing two approaches to oxygen therapy (ICU-ROX) pilot phase, which included the first 100 patients of an overall sample of 1000, was to examine feasibility.

DESIGN

Investigator-initiated, prospective, parallel-group, pilot randomised controlled trial.

SETTING

Six medical-surgical intensive care units (ICUs) in Australia and New Zealand, with participants recruited from September 2015 through June 2016.

PARTICIPANTS

100 patients ≥ 18 years of age who required invasive mechanical ventilation in the ICU and were expected to be receiving it beyond the next calendar day at the time of randomisation.

INTERVENTIONS

Conservative oxygen therapy or standard care.

MAIN OUTCOME MEASURES

Eligibility, recruitment rate, and separation in oxygen exposure (fraction of inspired oxygen [FiO₂] and oxygen saturation measured by pulse oximetry [SpO₂Z]).

RESULTS

94 of 99 participants (94.9%) were confirmed by study monitors to fulfil the study eligibility criteria. 3.6 patients per site per month were enrolled (95% confidence interval [CI], 2.5-4.7). Patients allocated to conservative oxygen therapy spent significantly more time on an FiO₂ of 0.21 in the ICU; median, 31.5 hours (interquartile range [IQR], 7-63.5) for conservative oxygen therapy patients v 0 hours for standard oxygen therapy patients (IQR, 0-10; midpoint difference, 21.5 hours; 95% CI, 9-34; P < 0.0001). Patients allocated to conservative oxygen therapy spent less time in the ICU with an SpO₂Z of ≥ 97% than patients allocated to standard oxygen therapy; median, 18.5 hours (IQR, 5-46) for conservative oxygen therapy patients v 32 hours for standard oxygen therapy (IQR, 17-80; midpoint difference, 13.5 hours; 95% CI, 2-25; P = 0.02).

CONCLUSIONS

Our findings confirm the feasibility of completing the ICU-ROX trial without the need for substantive changes to the study protocol for the remaining 900 trial participants.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry (ANZCTRN 12615000957594).