Different low activated clotting time target anticoagulation protocols for patients during extracorporeal membrane oxygenation management: a retrospective cohort study

Introduction Anticoagulation management is crucial for patients to prevent serious complications during extracorporeal membrane oxygenation (ECMO). However, the optimal target for low activated clotting time (ACT) anticoagulation during ECMO remains unclear. Methods A retrospective cohort study was conducted, including patients who received ECMO support in the Second Affiliated Hospital of Harbin Medical University in China from April 2017 to May 2024. Eligible patients were categorized into low (180 s) ACT groups. Major outcomes included ECMO oxygenator change, bleeding and thromboembolic events. Results A total of 148 patients were included after applying the exclusion criteria and divided into the low ACT group ( n = 25, 16.9%), the medium ACT group ( n = 86, 58.1%), and the high ACT group ( n = 37, 25.0%). The baseline characteristics were not significantly different among the three groups. The oxygenator change rate did not show a statistically significant difference (low ACT group: 0.0%; medium ACT group: 8.1%; high ACT group: 8.1%; χ 2 = 1.96, p = 0.39). There was no significant difference in the proportion of bleeding events among the low ( n = 3, 12.0%), medium ( n = 15, 17.4%), and high ( n = 9, 24.3%) ACT groups ( χ 2 = 1.61, p = 0.45). The incidence of thromboembolic events showed no significant difference among the low ( n = 4, 16.0%), medium ( n = 16, 18.6%), and high ( n = 9, 24.3%) ACT groups ( χ 2 = 0.78, p = 0.68). Conclusion Different low ACT target anticoagulation protocols for patients during ECMO do not increase the risk of oxygenator change, bleeding and thromboembolism during ECMO management. These results can help clinicians choose appropriate ACT target anticoagulation for patients. Further prospective trials are needed to verify the low ACT target anticoagulation protocols. Clinical trial registration Chinese Clinical Trial Registry, ChiCTR2500100151, Registered 3 April, 2025.