Introduction: Extracorporeal membrane oxygenation (ECMO) is a life-sustaining therapy for patients who have failed conventional management strategies. Veno-venous (VV) ECMO is used for acute respiratory failure and as a bridge to lung transplantation. The 2021 ELSO Anticoagulation Guidelines suggest that low-dose or even no anticoagulation may be feasible in VV-ECMO, though existing evidence primarily involves unfractionated heparin. This study aimed to evaluate the safety and efficacy of a low-dose bivalirudin anticoagulation strategy in patients requiring VV-ECMO. Methods: This prospective, observational study included consecutive patients cannulated for VV-ECMO between November 2024 to present at a high-volume academic ECMO center. Patients were excluded if they received veno-arterial ECMO or required therapeutic anticoagulation. Eligible patients were initiated on bivalirudin post-cannulation at 20 mcg/kg/min, titrated to a target activated partial thromboplastin time (PTT) of 40–60 seconds. Feasibility endpoints included median PTT, time to goal PTT, and number of titrations to achieve goal. Clinical outcomes, including major bleeding and thrombotic events, were compared to a previously published institutional historical cohort of 97 VV-ECMO patients managed with bivalirudin targeting a PTT goal of 61–75 seconds. Results: Eighteen patients met inclusion criteria, with a median age of 62 years and 67% were male. Most patients (78%) were cannulated pre- or post-lung transplantation, while 22% had ARDS. Study endpoints were reached through successful weaning (50%), death (23%), or conversion to another ECMO strategy (22%). Across 97 ECMO days, the median duration of support was 3.5 days per patient. Median time to goal PTT was 9.6 hours, with 78% of patients requiring no dose titrations. Among 327 PTT values, the median was 47.7 seconds. Compared to our historical cohort there were non-significant reductions in major bleeding (17% vs. 18%, p=1), any bleeding (22% vs. 28%, p=0.78), and circuit thrombosis 6% vs. 16%, p=0.46). Conclusions: A low-dose bivalirudin anticoagulation strategy for VV-ECMO patients was feasible, achieved target PTT with minimal titration, and maintained comparable safety and efficacy to historical controls, underscoring the need for continued investigation.
Rivosecchi et al. (Sun,) studied this question.