ID:175 FC-D11-2 Effectiveness and safety of a pump-controlled retrograde trial off-based weaning protocol for V-A ECMO

Background: Determining the optimal timing for weaning from V-A ECMO remain challenging. Conventional weaning involves gradually reduction of ECMO flow with serial hemodynamic and echocardiographic assessments, although risk of inadequate cardiac function evaluation remains. Pump-controlled retrograde trial off (PCRTO) is a weaning strategy that reduces the pump speed to create a controlled retrograde flow, which has the potential to accurately simulate weaning off ECMO. We performed a retrospective analysis to evaluate the safety and effectiveness of an institutional PCRTO-based weaning protocol. Methods: This protocol includes the following three steps with assessment of predefined hemodynamic and echocardiographic parameters: (1) reduction of ECMO flow to 2.0 L/min to assess readiness to wean; (2) stepwise reduction of ECMO flow to 1.5–1.0 L/min; (3) reduction of pump speed to achieve retrograde flow of -10 mL/kg/min. We retrospectively reviewed patients decannulated from ECMO using this protocol from 2024 to 2026. The primary efficacy outcome was ECMO weaning failure defined as cardiopulmonary arrest or ECMO re-insertion within 24 hours after ECMO decannulation. The safety outcome was thromboembolic events occurring from the first weaning trial to 24 hours after ECMO decannulation. Results: Nine patients were included, with a mean age of 58 years. Extracorporeal cardiopulmonary resuscitation was performed in 66% of the patients. The median time from ECMO initiation to the initial weaning trial was 3 days. One patient failed the initial weaning trial and required a second trial. As the primary outcome, none of the nine patients experienced ECMO weaning failure after successful PCRTO-based weaning trial. One patient developed a thromboembolic occlusion in the femoral artery after surgical repair, which was considered unrelated to PCRTO. Conclusions: This PCRTO-based weaning protocol for V-A ECMO was feasible and safe and may represent a promising strategy for ECMO weaning assessment.