Abstract 16543: Severe Thrombocytopenia is Common in Adults Undergoing Venoarterial Extracorporeal Membrane Oxygenation and is Predictive of Hemorrhage

Introduction: Extracorporeal membrane oxygenation (ECMO) is used to provide circulatory support and facilitate gas exchange via cardiopulmonary bypass. The relationship between ECMO and the incidence of severe thrombocytopenia (platelet count 9 /L) and subsequent clinical consequences are ill defined. We aimed to identify the risk factors for the development of thrombocytopenia and its clinical implications. Methods: This is a single-center retrospective cohort study of adults who received venoarterial (VA) ECMO. We examined consecutive platelet counts while on ECMO. Univariate logistic regression was used to determine if mean platelet count, platelet count range, or severe thrombocytopenia were predictors of overall survival, hemorrhage and thrombosis. A multivariate logistic regression model was used to identify factors that contribute to the development of the aforementioned patient outcomes. Results: In our cohort, 33 patients were included with a mean age of 55 years and duration of ECMO of 5.9 days. All patients received heparin, 33.3% received antiplatelet therapy and 45.5% developed severe thrombocytopenia. In univariate, analysis the development of severe thrombocytopenia increased the odds of major bleeding by 450% (OR 5.500, 95% CI 1.219 - 24.813, P -value 0.027), and the odds of surviving hospitalization decreased 84.1% (OR 0.159, 95% CI 0.033 - 0.773, P -value 0.023). Multivariate logistic regression controlling for additional clinical variables found no significant association between the development of severe thrombocytopenia and rates of thrombosis, hemorrhage, or overall survival. Platelet count decreased over time while on ECMO. Conclusions: Nearly half of the patients requiring VA-ECMO developed severe thrombocytopenia, which was associated with an increased risk of hemorrhage and in-hospital mortality. Additional studies are required to clarify the clinical implications of severe thrombocytopenia in ECMO patients.