PICO Summary: Does extracorporeal membrane oxygenation (ECMO) compared to conventional ventilator support reduce mortality and childhood disability in term or late preterm infants with severe respiratory failure?

BackgroundExtracorporeal membrane oxygenation (ECMO) is a complex technique for providing life support in severe but potentially reversible respiratory failure. The technique oxygenates blood outside the body, obviating the need for gas exchange in the lungs and, if necessary, provides cardiovascular support. In 1975 Bartlett reported the first mature newborn treated successfully with ECMO and other reports soon followed (Bartlett et al., 1976). However, ECMO is an extremely invasive, technically involved and expensive procedure. Therefore, there is a need for rigorous evaluation of its advantages and disadvantages to guide practice.
ParticipantsInfants with severe but potentially reversible respiratory failure, aged less than 28 days, with gestation at birth of 34 weeks or more.
InterventionExtracorporeal membrane oxygenation (ECMO).
ComparisonConventional ventilator support.
Outcome(s)Mortality, disability and use of health service resources.
StudiesRandomized or quasi-randomized controlled trials.
Study description and settingFour trials were identified in the review of Mugford and coworkers (Mugford 2008). The four trials (three USA and one UK) recruited clinically similar groups of infants (Barlett et al., 1985; O'Rourke et al., 1989; Bifano et al., 1992; UK Collaborative ECMO Trial Group, 1996). Two trials excluded infants with congenital diaphragmatic hernias. In two trials, transfer for ECMO implied transport over long distances. Two trials had follow-up information. One study included economic evaluation. The three USA trials had very small numbers of patients. Two trials used conventional randomization with low potential for bias. Two used less usual designs, which led to difficulties in their interpretation.
ResultsAll four trials showed strong benefit of ECMO on mortality (typical RR 0.44; 95% CI 0.31, 0.61, NNT 3(2–5)), especially for babies without congenital diaphragmatic hernia (typical RR 0.33, 95% CI 0.21, 0.53, NNT 3(2–5)). The UK trial provided follow-up information about death or severe disability, and cost-effectiveness, and showed benefit of ECMO at 1 year (RR 0.56, 95% CI 0.40, 0.78, NNT 4(3–7)), 4 years (RR 0.62, 95% CI 0.45, 0.86, NNT 5(3–12)), and 7 years (RR 0.64, 95% CI 0.47, 0.86, NNT 5(3–12)). Overall nearly half of the children recruited had died or were severely disabled by 7 years of age, reflecting the severity of their underlying conditions. A policy of ECMO is as cost-effective as other intensive care technologies in common use.
Confidence in resultsDespite being unblinded, the trials represent high quality evidence for all primary outcomes reported.
Key figure(s)Thumbnail image of
Figure captionDeath before discharge home
Search for eligible studiesCENTRAL, MEDLINE, were searched through 2007.
ConclusionsThere is a highly significant benefit of ECMO on mortality in infants with severe respiratory failure, especially for those infants without congenital diaphragmatic hernia. In the one large follow-up trial, clear benefits were demonstrated on death or severe disability and cost-effectiveness.
CitationMugford M, Elbourne D, Field D. Extracorporeal membrane oxygenation for severe respiratory failure in newborn infants. Cochrane Database of Systematic Reviews 2008, Issue 3. Art. No.: CD001340. DOI: 10.1002/14 651 858.CD001340.pub2.
Date completed22 February 2010
People who helped prepare this Cochrane PICO:Roger Soll and Martin Offringa, editors