Bleeding and Thrombotic Events During Extracorporeal Membrane Oxygenation for Postcardiotomy Shock

Anticoagulation therapy management during venoarterial extracorporeal membrane oxygenation (ECMO) is particularly difficult in postcardiotomy shock patients given a significant bleeding risk. We sought to determine the effect of anticoagulation treatment on bleeding and thrombosis risk for postcardiotomy shock patients on ECMO.

We retrospectively reviewed patients who received ECMO for postcardiotomy shock from July 2007 through July 2019. Characteristics of patients who had bleeding and thrombosis were investigated, and risk factors were assessed by multilevel logistic regression.

Of the 152 patients who received ECMO for postcardiotomy shock, 33 (23%) had 40 thrombotic events and 64 (45%) had 86 bleeding events. Predictors of bleeding were intraoperative packed red blood cell transfusion (odds ratio [OR] 1.05; 95% confidence interval [CI], 1.01 to 1.09), platelet transfusion (OR 1.10; 95% CI, 1.05 to 1.16), international normalized ratio (OR 1.18; 95% CI, 1.02 to 1.37), and activated partial thromboplastin time greater than 60 seconds (OR 2.32; 95% CI, 1.14 to 4.73). Predictors of thrombosis were anticoagulant use (OR 0.39; 95% CI, 0.19 to 0.79), surgical venting (OR 3.07; 95% CI, 1.29 to 7.31), hemoglobin (OR 1.38; 95% CI, 1.06 to 1.79), and central cannulation (OR 2.06; 95% CI, 1.03 to 4.11). The daily predicted probability of thrombosis was between 0.075 and 0.038 for patients who did not receive anticoagulation and decreased to between 0.030 and 0.013 for patients who received anticoagulation treatment at activated partial thromboplastin times between 25 and 80 seconds.

Anticoagulation therapy can reduce thromboembolic events in postcardiotomy shock patients on ECMO, but bleeding risk may outweigh this benefit at activated partial thromboplastin times greater than 60 seconds.