[Source: JAMA, full text: (LINK). Abstract, edited.]

ONLINE FIRST
<CITE><ABBR>JAMA.</ABBR> Published online October 5, 2011.doi: 10.1001/jama.2011.1471</CITE>
Referral to an Extracorporeal Membrane Oxygenation Center and Mortality Among Patients With Severe 2009 Influenza A(H1N1)


Moronke A. Noah, MRCS; Giles J. Peek, FRCS (CTh), MD; Simon J. Finney, FRCA, PhD; Mark J. Griffiths, MRCP, PhD; David A. Harrison, PhD; Richard Grieve, PhD; M. Zia Sadique, PhD; Jasjeet S. Sekhon, PhD; Daniel F. McAuley, FRCP, MD; Richard K. Firmin, FRCS; Christopher Harvey, MRCS; Jeremy J. Cordingley, FRCA, MD; Susanna Price, MRCP, PhD; Alain Vuylsteke, FRCA, MD; David P. Jenkins, FRCS (CTh); David W. Noble, FFICM; Roxanna Bloomfield, FRCA; Timothy S. Walsh, FRCA, MD; Gavin D. Perkins, MRCP, MD; David Menon, FMedSci, PhD; Bruce L. Taylor, FRCA, FCICM; Kathryn M. Rowan, PhD

Author Affiliations:

Heartlink ECMO Centre, Glenfield Hospital, Leicester, England (Drs Noah, Peek, Firmin, and Harvey); Department of Anaesthesia, Royal Brompton Hospital, London, England (Drs Finney, Griffiths, Cordingley, and Price); Intensive Care National Audit & Research Centre, London, England (Drs Harrison and Rowan); Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, England (Drs Grieve and Sadique); Travers Department of Political Science, University of California, Berkeley (Dr Sekhon); Centre for Infection and Immunity, Queens University of Belfast, Belfast, Ireland (Dr McAuley); Department of Anaesthesia, Papworth Hospital, Cambridge, England (Drs Vuylsteke and Jenkins); Department of Anaesthesia, Aberdeen Royal Infirmary, Aberdeen, Scotland (Drs Noble and Bloomfield); Department of Critical Care Medicine, University of Edinburgh, Edinburgh, Scotland (Dr Walsh); Warwick Clinical Trials Unit, University of Warwick, Coventry, England (Dr Perkins); Division of Anaesthesia, University of Cambridge, Cambridge, England (Dr Menon); and Department of Critical Care, Portsmouth Hospitals NHS Trust, Portsmouth, England (Dr Taylor).


Abstract

Context

Extracorporeal membrane oxygenation (ECMO) can support gas exchange in patients with severe acute respiratory distress syndrome (ARDS), but its role has remained controversial. ECMO was used to treat patients with ARDS during the 2009 influenza A(H1N1) pandemic.


Objective

To compare the hospital mortality of patients with H1N1-related ARDS referred, accepted, and transferred for ECMO with matched patients who were not referred for ECMO.


Design, Setting, and Patients

A cohort study in which ECMO-referred patients were defined as all patients with H1N1-related ARDS who were referred, accepted, and transferred to 1 of the 4 adult ECMO centers in the United Kingdom during the H1N1 pandemic in winter 2009-2010. The ECMO-referred patients and the non?ECMO-referred patients were matched using data from a concurrent, longitudinal cohort study (Swine Flu Triage study) of critically ill patients with suspected or confirmed H1N1. Detailed demographic, physiological, and comorbidity data were used in 3 different matching techniques (individual matching, propensity score matching, and GenMatch matching).


Main Outcome Measure

Survival to hospital discharge analyzed according to the intention-to-treat principle.


Results

Of 80 ECMO-referred patients, 69 received ECMO (86.3%) and 22 died (27.5%) prior to discharge from the hospital. From a pool of 1756 patients, there were 59 matched pairs of ECMO-referred patients and non?ECMO-referred patients identified using individual matching, 75 matched pairs identified using propensity score matching, and 75 matched pairs identified using GenMatch matching. The hospital mortality rate was 23.7% for ECMO-referred patients vs 52.5% for non?ECMO-referred patients (relative risk [RR], 0.45 [95% CI, 0.26-0.79]; P = .006) when individual matching was used; 24.0% vs 46.7%, respectively (RR, 0.51 [95% CI, 0.31-0.81]; P = .008) when propensity score matching was used; and 24.0% vs 50.7%, respectively (RR, 0.47 [95% CI, 0.31-0.72]; P = .001) when GenMatch matching was used. The results were robust to sensitivity analyses, including amending the inclusion criteria and restricting the location where the non?ECMO-referred patients were treated.


Conclusion

For patients with H1N1-related ARDS, referral and transfer to an ECMO center was associated with lower hospital mortality compared with matched non?ECMO-referred patients.
-
-------