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Objectives: To determine the actual cost and drivers of the cost of an extracorporeal cardiopulmonary resuscitation (E-CPR) care cycle., Perspective: A time-driven activity-based costing study conducted from a healthcare provider perspective., Setting: A quaternary care ICU providing around-the-clock E-CPR service for out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA) in Australia., Methods: The E-CPR care cycle was defined as the time from initiating E-CPR to hospital discharge or death of the patient. Detailed process maps with discrete steps and probabilistic decision nodes accounting for the complex trajectories of E-CPR patients were developed. Data about clinical and nonclinical resources and timing of activities was collected multiple times for each process . Total direct costs were calculated using the time estimates and unit costs per resource for all clinical and nonclinical resources. The total direct costs were combined with indirect costs to obtain the total cost of E-CPR., Results: From 10 E-CPR care cycles observed during the study period, a minimum of 3 observations were obtained per process. The E-CPR care cycle's mean (95% CI) cost was $75,014 ($66,209-83,222). Initiation of extracorporeal membrane oxygenation (ECMO) and ECMO management constituted 18% of costs. The ICU management (35%) and surgical costs (20%) were the primary cost determinants. IHCA had a higher mean (95% CI) cost than OHCA ($87,940 [75,372-100,570] vs. 62,595 [53,994-71,890], p < 0.01), mainly because of the increased survival and ICU length of stay of patients with IHCA. The mean cost for each E-CPR survivor was $129,503 ($112,422-147,224)., Conclusions: Significant costs are associated with E-CPR for refractory cardiac arrest. The cost of E-CPR for IHCA was higher compared with the cost of E-CPR for OHCA. The major determinants of the E-CPR costs were ICU and surgical costs. These data can inform the cost-effectiveness analysis of E-CPR in the future., Competing Interests: The authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2024 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)

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&lt;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., Competing Interests: Declaration of interests CLH leads the bi-national EXCEL registry, with funding from the Australian National Health and Medical Research Council (NHMRC) and the Heart Foundation of Australia (HFA), holds an NHMRC investigator grant, and is on the executive committee of the International ECMO Network (ECMONet). AMH, AJCB, and DJC receive research support from NHMRC. AMH, MJB, SB, BJF, NJL, DJC, DJG, IKH, DVP, TVT, and AAU received funding for the EXCEL registry from NHMRC and HFA. DB is Chair of the Executive Committee of ECMONet and President-elect of ELSO, receives research support from ALung Technologies, and has been on medical advisory boards for Abiomed, Xenios, Medtronic, and Cellenkos. DJC holds an NHMRC practitioner fellowship. EF is on the executive committee of ECMONet and the steering committee of the Extracorporeal Life Support Organization (ELSO). JFF and VAP are on the Executive Committee of ECMONet. JFF is President of the Asia-Pacific Chapter of ELSO, Chair of the Queensland Cardiovascular Research Network, co-founder of BiVACOR, and receives research support from Xenios, Mallenkrodt Getinge, and MERA (all ECMO companies). DS received research support from a HFA fellowship. AAU is on the executive committee of the Australian and New Zealand Intensive Care Society Clinical Trials Group. All other authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Purpose: The purpose of this study was to systematically investigate the reporting of selection criteria and outcome measures, and to examine definitions of complications used in venoarterial extracorporeal membrane oxygenation studies (V-A ECMO)., Materials and Methods: Medline, EMBASE and the Cochrane central register were searched for V-A ECMO studies from January 2005 to July 2017. Studies with ≤99 patients or without patient centered outcomes were excluded. Two reviewers independently assessed search results and undertook data extraction., Results: Forty-six studies met the inclusion criteria, and all were retrospective, observational studies. Inconsistent reporting of selection criteria, ECMO management and outcome measures was common. In-hospital mortality was the most common primary outcome (41% of studies), followed by 30-day mortality (11%). Bleeding was the most frequent complication reported, most commonly defined as "bleeding requiring transfusion" (median ≥ 2 Units/day). Significant variation in reporting and definitions was also evident for vascular, neurological renal and infectious complications., Conclusion: This systematic review provides clinicians with the most commonly reported selection criteria, outcome measures and complications used in ECMO practice. However non-standardized definitions and inconsistent reporting limits their ability to inform practice. New consensus driven definitions of complications and patient centred outcomes are urgently needed., (Copyright © 2019. Published by Elsevier Inc.)

Objectives: To determine whether randomization of patients undergoing extracorporeal membrane oxygenation to either therapeutic or a low-dose anticoagulation protocol results in a difference in activated partial thromboplastin time and anti-Xa., Design: Randomized, controlled, unblinded study., Setting: Two ICUs of two university hospitals., Patients: Patients admitted to the ICU, who required extracorporeal membrane oxygenation (venovenous or venoarterial) and who did not have a preexisting indication for therapeutic anticoagulation., Interventions: Therapeutic anticoagulation with heparin (target activated partial thromboplastin time between 50 and 70 s) or lower dose heparin (up to 12,000 U/24 hr aiming for activated partial thromboplastin time < 45 s)., Measurements and Main Results: Thirty-two patients were randomized into two study groups that were not significantly different in demographics and extracorporeal membrane oxygenation characteristics. There was a significant difference in the daily geometric mean heparin dose (11,742 U [95% CI, 8,601-16,031 U] vs 20,710 U [95% CI, 15,343-27,954 U]; p = 0.004), daily geometric mean activated partial thromboplastin time (48.1 s [95% CI, 43.5-53.2 s] vs 55.5 s [95% CI, 50.4-61.2 s]; p = 0.04), and daily geometric mean anti-Xa (0.11 international units/mL [95% CI, 0.07-0.18] vs 0.27 [95% CI, 0.17-0.42]; p = 0.01). We found similar results when considering only venovenous extracorporeal membrane oxygenation episodes; however, no difference in daily geometric mean activated partial thromboplastin time between groups when considering only venoarterial extracorporeal membrane oxygenation episodes., Conclusions: Allocating patients on extracorporeal membrane oxygenation to two different anticoagulation protocols led to a significant difference in mean daily activated partial thromboplastin time and anti-Xa levels between groups. When considering subgroups analyses, these results were consistent in patients on venovenous extracorporeal membrane oxygenation. Our results support the feasibility of a larger trial in patients undergoing venovenous extracorporeal membrane oxygenation to compare different anticoagulation protocols; however, this study does not provide evidence on the optimal anticoagulation protocol for patients undergoing extracorporeal membrane oxygenation.

Purpose: This study was designed to examine the long-term survival of patients who survived to be weaned from venoarterial extracorporeal membrane oxygenation (VA ECMO) and to determine which factors present at initiation and during ECMO predict long-term survival. We further sought to develop the preliminary long-term outcome after VA ECMO score that would predict patient outcome and to assess its accuracy at various time points., Methods: We conducted a retrospective, observational cohort study of all patients with cardiogenic shock treated with VA ECMO at the Alfred Hospital, Australia, from January 2007 until February 2013. Overall, 125 patients underwent ECMO, and 104 patients were successfully weaned and formed the study population, with a median follow-up of 21 months (range, 0-84)., Results: Survival rates of those weaned from ECMO at 3 months, 12 months, and 2 years were 87%, 79%, and 71%, respectively, corresponding to overall survival rates at 3 months of 90 (72%) of 124; at 12 months, 80 (65%) of 122; and 24 months, 57 (57%) of 100. Ischemic heart disease, higher lactate and higher bilirubin at initiation of VA ECMO, and a longer duration of renal replacement therapy during ECMO were all independently associated with decreased length of survival. Long-term survival was found to be highly related to the number of these risk factors present up to 2 years afterward., Conclusion: Good long-term survival can be achieved in patients who have been successfully weaned from VA-ECMO. The factors present at initiation and during ECMO can relate to altered risk of long-term survival., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Rationale: Extracorporeal membrane oxygenation (ECMO) may provide mechanical pulmonary and circulatory support for patients with cardiogenic shock refractory to conventional medical therapy. Prediction of survival in these patients may assist in management of these patients and comparison of results from different centers., Aims: To identify pre-ECMO factors which predict survival from refractory cardiogenic shock requiring ECMO and create the survival after veno-arterial-ECMO (SAVE)-score., Methods and Results: Patients with refractory cardiogenic shock treated with veno-arterial ECMO between January 2003 and December 2013 were extracted from the international Extracorporeal Life Support Organization registry. Multivariable logistic regression was performed using bootstrapping methodology with internal and external validation to identify factors independently associated with in-hospital survival. Of 3846 patients with cardiogenic shock treated with ECMO, 1601 (42%) patients were alive at hospital discharge. Chronic renal failure, longer duration of ventilation prior to ECMO initiation, pre-ECMO organ failures, pre-ECMO cardiac arrest, congenital heart disease, lower pulse pressure, and lower serum bicarbonate (HCO3) were risk factors associated with mortality. Younger age, lower weight, acute myocarditis, heart transplant, refractory ventricular tachycardia or fibrillation, higher diastolic blood pressure, and lower peak inspiratory pressure were protective. The SAVE-score (area under the receiver operating characteristics [ROC] curve [AUROC] 0.68 [95%CI 0.64-0.71]) was created. External validation of the SAVE-score in an Australian population of 161 patients showed excellent discrimination with AUROC = 0.90 (95%CI 0.85-0.95)., Conclusions: The SAVE-score may be a tool to predict survival for patients receiving ECMO for refractory cardiogenic shock (www.save-score.com)., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

Objective: To describe mechanical ventilation settings in adult patients treated for an acute respiratory distress syndrome with extracorporeal membrane oxygenation and assess the potential impact of mechanical ventilation settings on ICU mortality., Design: Retrospective observational study., Setting: Three international high-volume extracorporeal membrane oxygenation centers., Patients: A total of 168 patients treated with extracorporeal membrane oxygenation for severe acute respiratory distress syndrome from January 2007 to January 2013., Interventions: We analyzed the association between mechanical ventilation settings (i.e. plateau pressure, tidal volume, and positive end-expiratory pressure) on ICU mortality using multivariable logistic regression model and Cox-proportional hazards model., Measurement and Main Results: We obtained detailed demographic, clinical, daily mechanical ventilation settings and ICU outcome data. One hundred sixty-eight patients (41 ± 14 years old; PaO2/FIO2 67 ± 19 mm Hg) fulfilled our inclusion criteria. Median duration of extracorporeal membrane oxygenation and ICU stay were 10 days (6-18 d) and 28 days (16-42 d), respectively. Lower positive end-expiratory pressure levels and significantly lower plateau pressures during extracorporeal membrane oxygenation were used in the French center than in both Australian centers (23.9 ± 1.4 vs 27.6 ± 3.7 and 27.8 ± 3.6; p < 0.0001). Overall ICU mortality was 29%. Lower positive end-expiratory pressure levels (until day 7) and lower delivered tidal volume after 3 days on extracorporeal membrane oxygenation were associated with significantly higher mortality (p < 0.05). In multivariate analysis, higher positive end-expiratory pressure levels during the first 3 days of extracorporeal membrane oxygenation support were associated with lower mortality (odds ratio, 0.75; 95% CI, 0.64-0.88; p = 0.0006). Other independent predictors of ICU mortality included time between ICU admission and extracorporeal membrane oxygenation initiation, plateau pressure greater than 30 cm H2O before extracorporeal membrane oxygenation initiation, and lactate level on day 3 of extracorporeal membrane oxygenation support., Conclusions: Protective mechanical ventilation strategies were routinely used in high-volume extracorporeal membrane oxygenation centers. However, higher positive end-expiratory pressure levels during the first 3 days on extracorporeal membrane oxygenation support were independently associated with improved survival. Further prospective trials on the optimal mechanical ventilation strategy during extracorporeal membrane oxygenation support are warranted.

Purpose: To assess the relationship between early daily fluid balance (FB) and 90-day outcome in adult patients treated with extracorporeal membrane oxygenation (ECMO)., Design: Retrospective observational study., Setting: Tertiary referral centre for ECMO., Patients: 115 patients treated with ECMO for refractory heart failure and 57 patients treated with ECMO for refractory respiratory failure., Methods: We analysed the association between early daily FB versus hospital and 90-day mortality using multivariable logistic regression model, Cox proportional-hazards model and propensity score., Results: We obtained detailed demographic, clinical, and biochemical data, daily FB, and continuous renal replacement days. Fifty-seven per cent of patients had acute kidney injury (AKI) at ECMO initiation, and 60 % (n = 103) of patients received continuous renal replacement therapy (CRRT) during ECMO course, beginning at a median of 1 (0-3.5) days after ECMO initiation. Overall 90-day mortality was 24 %. Survivors exhibited lower daily FB from day 3 to day 5. After adjustments, Acute Physiology and Chronic Health Evaluation (APACHE) III, CRRT during the first 3 days, major bleeding event at day 1 and positive FB on day 3 were independent predictors of 90-day mortality. Positive FB at ECMO day 3 remained an independent predictor of hospital and 90-day mortality, regardless of the statistical model used or the inclusion of a propensity score to have positive FB., Conclusions: Positive FB at ECMO day 3 is an independent predictor of 90-day mortality. Further interventional studies aimed at testing the value of strategy of tight control of FB during the early ECMO period are now warranted.

Rationale: Increasing use of extracorporeal membrane oxygenation (ECMO) for acute respiratory failure may increase resource requirements and hospital costs. Better prediction of survival in these patients may improve resource use, allow risk-adjusted comparison of center-specific outcomes, and help clinicians to target patients most likely to benefit from ECMO., Objectives: To create a model for predicting hospital survival at initiation of ECMO for respiratory failure., Methods: Adult patients with severe acute respiratory failure treated by ECMO from 2000 to 2012 were extracted from the Extracorporeal Life Support Organization (ELSO) international registry. Multivariable logistic regression was used to create the Respiratory ECMO Survival Prediction (RESP) score using bootstrapping methodology with internal and external validation., Measurements and Main Results: Of the 2,355 patients included in the study, 1,338 patients (57%) were discharged alive from hospital. The RESP score was developed using pre-ECMO variables independently associated with hospital survival on logistic regression, which included age, immunocompromised status, duration of mechanical ventilation before ECMO, diagnosis, central nervous system dysfunction, acute associated nonpulmonary infection, neuromuscular blockade agents or nitric oxide use, bicarbonate infusion, cardiac arrest, PaCO2, and peak inspiratory pressure. The receiver operating characteristics curve analysis of the RESP score was c = 0.74 (95% confidence interval, 0.72-0.76). External validation, performed on 140 patients, exhibited excellent discrimination (c = 0.92; 95% confidence interval, 0.89-0.97)., Conclusions: The RESP score is a relevant and validated tool to predict survival for patients receiving ECMO for respiratory failure.

The timing of extracorporeal membrane oxygenation (ECMO) initiation and its outcome in the management of respiratory and cardiac failure have received considerable attention, but very little attention has been given to mechanical ventilation during ECMO. Mechanical ventilation settings in non-ECMO studies have been shown to have an effect on survival and may also have contributed to a treatment effect in ECMO trials. Protective lung ventilation strategies established for non-ECMO-supported respiratory failure patients may not be optimal for more severe forms of respiratory failure requiring ECMO support. The influence of positive end-expiratory pressure on the reduction of the left ventricular compliance may be a matter of concern for patients receiving ECMO support for cardiac failure. The objectives of this review were to describe potential mechanisms for lung injury during ECMO for respiratory or cardiac failure, to assess the possible benefits from the use of ultra-protective lung ventilation strategies and to review published guidelines and expert opinions available on mechanical ventilation-specific management of patients requiring ECMO, including mode and ventilator settings. Articles were identified through a detailed search of PubMed, Ovid, Cochrane databases and Google Scholar. Additional references were retrieved from the selected studies. Growing evidence suggests that mechanical ventilation settings are important in ECMO patients to minimize further lung damage and improve outcomes. An ultra-protective ventilation strategy may be optimal for mechanical ventilation during ECMO for respiratory failure. The effects of airway pressure on right and left ventricular afterload should be considered during venoarterial ECMO support of cardiac failure. Future studies are needed to better understand the potential impact of invasive mechanical ventilation modes and settings on outcomes.

This study reports Aspergillus isolation in critically ill patients who underwent extracorporeal membrane oxygenation (ECMO) and highlights the difficulty in establishing a diagnosis of aspergillosis in this population. The diagnosis of Aspergillus infection or colonization was retrospectively performed using the proposed modified criteria of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group (EORTC/MSG) adapted to critically ill patients. Between 2005 and 2011, 11 of 151 patients (7.2%) who underwent ECMO had Aspergillus sp. isolates, 10 in a pulmonary sample and 1 in a mediastinal wound sample. Five patients did not have any classical risk factors for aspergillosis. One patient had a proven invasive pulmonary aspergillosis (IPA), 2 had a putative IPA, and 1 patient had a possible Aspergillus mediastinitis, whilst in 7 patients this was considered colonization. However, the clinical relevance of Aspergillus isolation was based on an algorithm not validated in patients undergoing ECMO. Our data support the need to implement non-invasive diagnostic procedures for aspergillosis in this population.

Introduction: Mortality of patients on extracorporeal membrane oxygenation (ECMO) remains high. The objectives of this study were to assess the factors associated with outcome of patients undergoing ECMO in a large ECMO referral centre and to compare veno-arterial ECMO (VA ECMO) with veno-venous ECMO (VV ECMO)., Methods: We reviewed a prospectively obtained ECMO database and patients' medical records between January 2005 and June 2011. Demographic characteristics, illness severity at admission, ECMO indication, organ failure scores before ECMO and the ECMO mode and configuration were recorded. Bleeding, neurological, vascular and infectious complications that occurred on ECMO were also collected. Demographic, illness, ECMO support descriptors and complications associated with hospital mortality were analysed., Results: ECMO was initiated 158 times in 151 patients. VA ECMO (66.5%) was twice as common as VV ECMO (33.5%) with a median duration significantly shorter than for VV ECMO (7 days (first and third quartiles: 5; 10 days) versus 10 days (first and third quartiles: 6; 16 days)). The most frequent complications during ECMO support were bleeding and bloodstream infections regardless of ECMO type. More than 70% of the ECMO episodes were successfully weaned in each ECMO group. The overall mortality was 37.3% (37.1% for the patients who underwent VA ECMO, and 37.7% for the patients who underwent VV ECMO). Haemorrhagic events, assessed by the total of red blood cell units received during ECMO, were associated with hospital mortality for both ECMO types., Conclusions: Among neurologic, vascular, infectious and bleeding events that occurred on ECMO, bleeding was the most frequent and had a significant impact on mortality. Further studies are needed to better investigate bleeding and coagulopathy in these patients. Interventions that reduce these complications may improve outcome.

Objectives: To analyze infectious complications that occur in patients who receive extracorporeal membrane oxygenation (ECMO), associated risk factors, and consequences on patient outcome., Design: Retrospective observational survey from 2005 through 2011., Participants and Setting: Patients who required ECMO in an Australian referral center., Methods: Cases of bloodstream infection (BSI), catheter-associated urinary tract infection (CAUTI), and ventilator-associated pneumonia (VAP) that occurred in patients who received ECMO were analyzed., Results: A total of 146 ECMO procedures were performed for more than 48 hours in 139 patients, and 36 patients had a total of 46 infections (30.1 infectious episodes per 1,000 days of ECMO). They included 24 cases of BSI, 6 of them secondary to VAP; 23 cases of VAP; and 5 cases of CAUTI. The most frequent pathogens were Enterobacteriaceae (found in 16 of 46 cases), and Candida was the most common cause of BSI (in 9 of 24 cases). The Sequential Organ Failure Assessment score before ECMO initiation and the number of days of support were independently associated with a risk of BSI, with odds ratios of 1.23 (95% confidence interval [CI], 1.03-1.47; [Formula: see text]) and 1.08 (95% CI, 1.03-1.19]; [Formula: see text]), respectively. Infected patients did not have a significantly higher mortality compared with uninfected patients (41.7% vs 32%; [Formula: see text]), but intensive care unit length of stay (16 days [interquartile range, 8-26 days] vs 11 days [IQR, 4-19 days]; [Formula: see text]) and hospital length of stay (33.5 days [interquartile range, 15.5-55.5] vs 24 days [interquartile range, 9-42 days]; [Formula: see text]) were longer., Conclusion: The probability of infection increased with the duration of support and the severity of illness before initiation of ECMO. Infections affected length of stay but did not have an impact on mortality.

Introduction: The purpose of the study was to assess the long term outcome and quality of life of patients with acute respiratory distress syndrome (ARDS) receiving extracorporeal membrane oxygenation (ECMO) for refractory hypoxemia., Methods: A retrospective observational study with prospective health related quality of life (HRQoL) assessment was conducted in ARDS patients who had ECMO as a rescue therapy for reversible refractory hypoxemia from January 2009 until April 2011 in a tertiary Australian centre. Survival and long-term quality of life assessment, using the Short-Form 36 (SF-36) and the EuroQol health related quality of life questionnaire (EQ5D) were assessed and compared to international data from other research groups., Results: Twenty-one patients (mean age 36.3 years) with ARDS receiving ECMO for refractory hypoxemia were studied. Eighteen (86%) patients were retrieved from external intensive care units (ICUs) by a dedicated ECMO retrieval team. Eleven (55%) had H1N1 influenza A-associated pneumonitis. Eighteen (86%) patients survived to hospital discharge. Of the 18 survivors, ten (56%) were discharged to other hospitals and 8 (44%) were discharged directly home. Sequelae and health related quality of life were evaluated for 15 of the 18 (71%) long-term survivors (assessment at median 8 months). Mean SF-36 scores were significantly lower across all domains compared to age and sex matched Australian norms. Mean SF-36 scores were lower (minimum important difference at least 5 points) than previously described ARDS survivors in the domains of general health, mental health, vitality and social function. One patient had long-term disability as a result of ICU acquired weakness. Only 26% of survivors had returned to previous work levels at the time of follow-up., Conclusions: This ARDS cohort had a high survival rate (86%) after use of ECMO support for reversible refractory hypoxemia. Long term survivors had similar physical health but decreased mental health, general health, vitality and social function compared to other ARDS survivors and an unexpectedly poor return to work.