Extracorporeal membrane oxygenation (ECMO) in patients with severe
COVID-19 adult respiratory distress syndrome: a systematic review and
meta-analysis
Abstract
Background COVID 19 is the most recent cause of Adult respiratory
distress syndrome ARDS. Extracorporeal membrane oxygenation (ECMO) can
support gas exchange in patients failing conventional mechanical
ventilation, but its role is still controversial. We conducted a
systematic review and meta-analysis on ECMO for COVID-associated ARDS to
study its outcome. Materials and Methods CENTRAL, MEDLINE/PubMed,
Cochrane Library, and Scopus were systematically searched from inception
to May 28, 2020. Studies reporting five or more patients with COVID 19
infection treated venovenous with ECMO were included. The main outcome
assessed was mortality. Baseline, procedural, outcome, and validity data
were systematically appraised and pooled with random-effect methods. The
validity of all the included observational studies was appraised with
the Newcastle Ottawa scale. Meta-regression and publication bias were
tested. This trial was registered with PROSPERO under registration
number CRD42020183861 Results From 1647 initial citations, 34 full text
articles were analysed and 12 studies were selected, including 194
patients with confirmed COVID 19 infection requiring ICU admission and
venovenous ECMO treatment. Random-effect pooled estimates suggested an
overall in-hospital mortality risk ratio of 0.49 (95% confidence
interval 0.259 to 0.721; I2 = 94%). Subgroup analysis according to
country of origin showed persistent heterogeneity only in the 7 Chinese
studies with pooled estimate mortality risk ratio of 0.66 (I2 = 87%)
(95% CI = 0.39-0.93), while the later larger studies coming from the
USA showed pooled estimate mortality risk ratio of 0.41 (95% CI
0.28-0.53) with homogeneity (p=0.67) similar to France with a pooled
mortality risk ratio of 0.26 (95% CI 0.08-0.43) with homogeneity
(p=0.86).