Bivalirudin versus heparin as an anticoagulant during extracorporeal membrane oxygenation: a case-control study

Objective: Heparin-based anticoagulation for patients undergoing extracorporeal membrane oxygenation has many limitations, including a high risk of heparin-induced thrombocytopenia. However, little experience with other anticoagulants in these patients has been described. The aim of this study was to compare bivalirudin-based anticoagulation with heparin-based protocols in a population of patients treated with venovenous or venoarterial extracorporeal membrane oxygenation. Design: In this case-control study, 10 patients received bivalirudin (cases) and 10 heparin (controls). The target activated partial thromboplastin time (aPTT) was 45 to 60 seconds. Interventions: None. Measurements and Main Results: aPTT variations >20% of the previous value were much more frequent in patients treated with heparin than in patients receiving bivalirudin (52 v 24, p < 0.001). The number of corrections of the anticoagulant dose was higher in the heparin group compared with the bivalirudin group (58 v 51), although it did not reach statistical significance. Bleeding, thromboembolic complications, extracorporeal membrane oxygenation (ECMO) support duration, mortality, and the number of episodes of aPTT >80 seconds were not different between the 2 groups. A further analysis was performed in the bivalirudin group according to the presence of acute renal failure requiring continuous venovenous hemofiltration. The median bivalirudin dose in patients with or without hemofiltration was 0.041 (0.028-0.05) mg/kg/h and 0.028 (0-0.041) mg/kg/h, respectively (p = 0.2). Conclusions: Bivalirudin-based anticoagulation may represent a new method of anticoagulation for reducing thromboembolic and bleeding complications, which still jeopardize the application of extracorporeal membrane oxygenation. Moreover, bivalirudin is free from the risk of heparin-induced thrombocytopenia. Higher doses of bivalirudin may be needed in patients undergoing hemofiltration.