Meta-Analysis Comparing Bivalirudin Versus. Unfractionated Heparin in Adult Patients With Extracorporeal Membrane Oxygenation

Introduction: Unfractionated heparin (UFH) has traditionally been the agent of choice in patients on extracorporeal membrane oxygenation (ECMO). However, direct thrombin inhibitors (DTI) have recently garnered more attention in ECMO because of their advantages over UFH. Given the heterogeneous results of multiple recent published studies, we performed a meta-analysis to describe pooled outcomes between bivalirudin and UFH anticoagulation in patients on ECMO. Methods: Relevant studies were identified from MEDLINE and Google Scholar database searches through April 23, 2022. The primary efficacy outcome was thromboembolism (TE), and secondary efficacy outcomes included all-cause mortality and circuit thrombosis. The primary safety outcome was major bleeding. Results: A total of 6 studies were included in the meta-analysis. Bivalirudin use was associated with significantly lower risk of TE (OR 0.61; 95% CI 0.38-.99; P = .05; I-2 = 0%) and circuit thrombosis (OR 0.51; 95% CI .32-.80; P = .004; I-2 = 0%) compared with UFH. There was no significant difference in all-cause mortality risk (OR 0.75; 95% CI .52-1.09; P = .13; I-2 = 30%) between the bivalirudin and UFH groups. No significant difference in the risk of major bleeding between 2 groups was found (OR 0.67; 95% CI 0.25-1.81; P = .43; I-2 = 80%). Conclusion: These data support that bivalirudin is a reasonable alternative to UFH in patients on ECMO. Randomized controlled trials are needed to confirm bivalirudin's efficacy and safety results compared with UFH.