Methods: Between April 1st, 2020 and January 31st, 2022, a total of 52 adult patients (32 males, 20 females; mean age: 44.5±11.5 years; range, 21 to 71 years) who received extracorporeal membrane oxygenation due to COVID-19-associated acute respiratory distress syndrome and whose anticoagulant treatment consisted of bivalirudin plus aspirin were retrospectively analyzed. During the first 10 days of extracorporeal membrane oxygenation, bivalirudin dosing, activated partial thromboplastin time, and activated clotting time, as well as major bleeding events and patient and/or ECMO-circuit thromboses were recorded.
Results: The mean bivalirudin dose per day ranged from 0.03 to 0.04 mg/kg/h, with a mean overall dose of 0.036 mg/kg/h. The mean activated partial thromboplastin time was 49.1±6.9 sec throughout 10 days of the application. The percentage of time in the target range for activated partial thromboplastin time was 58.9±20.1% within 10 days of application, compared to 33.1±31.1% for the first 24 h. The mean daily activated clotting time was below the target range within the first three days, but it was consistently within the target range after Day 3. During the first 10 days of the application, no mortality occurred. Major bleeding occurred in 11 patients (21.1%) and circuit thrombosis occurred in three patients (5.8%).
Conclusion: In patients receiving extracorporeal membrane oxygenation for COVID-19-associated acute respiratory distress syndrome, an hourly bivalirudin dose of 0.03 to 0.04 mg/kg/h throughout the first 10 days of application was associated with the targeted anticoagulation profile of 45 to 60 sec. The combination was associated with a comparable rate of major bleeding, but a lower rate of circuit-thrombosis compared to the literature reports.