Risk Factors of Bleeding in Patients Undergoing Venoarterial Extracorporeal Membrane Oxygenation

Background: Venoarterial extracorporeal membrane oxygenation (VA ECMO) is increasingly being used for circulatory shock. Bleeding is a frequent complication and is associated with increased mortality. The purpose of our study was to identify factors associated with early major bleeding after VA ECMO initiation.

Methods: We performed a retrospective observational study based on our database. In accordance with the Extracorporeal Life Support Organization definition, the population was divided in two groups: major bleeding events (group B) and no major bleeding events (group O). We collected data on all major bleeding events occurring during the first 48 hours after VA ECMO initiation.

Results: Of the 243 patients analyzed, 111 patients (46%) had an early major bleeding event. Independent risk factors associated with early major bleeding events were postcardiotomy VA ECMO (odds ratio [OR] 1.98; 95% confidence interval [CI], 1.08 to 3.62; P = .02), body mass index (OR 0.91; 95% CI, 0.85 to 0.98; P = .01), hemoglobinemia (OR 0.8; 95% CI, 0.7 to 0.92; P = .002), fibrinogen (OR 0.67; 95% CI, 0.52 to 0.84; P = .001), and pH (OR 0.15; 95% CI, 0.02 to 1.04; P = .05). By using a receiver-operating characteristics curve analysis, hemoglobin level less than 9 g dL^-1, fibrinogen level less than 2 g L^-1, pH lower than 7.12, and body mass index below 25 kg/m² were identified to predict early major bleeding events. Major bleeding events were independently associated with mortality (OR 2.54; CI 95%, 1.38 to 4.66; P = .01).

Conclusions: We found that postcardiotomy VA ECMO, hemoglobin levels less than 9 g dL^-1, fibrinogen levels less than 2 g L^-1, pH lower than 7.12, and body mass index below 25 kg/m² were associated with a higher risk for early major bleeding events.