Low-Intensity vs Moderate-Intensity Anticoagulation for Venovenous Extracorporeal Membrane Oxygenation: The Strategies for Anticoagulation During Venovenous Extracorporeal Membrane Oxygenation Pilot Trial.

Summary

In this multicenter pilot RCT (n=26), low-intensity vs moderate-intensity anticoagulation during vvECMO was feasible with complete protocol adherence. Major bleeding was less frequent with low-intensity anticoagulation (8.3% vs 28.6%), with similar thromboembolic events, supporting the feasibility of a larger efficacy trial.

Key Findings

• Feasibility established: all 26 randomized patients received the assigned anticoagulation intensity across 3 centers.
• Major bleeding was lower with low-intensity anticoagulation (8.3%) vs moderate-intensity (28.6%); P=0.33 (underpowered).
• Thromboembolic events were rare and similar (1 vs 0), and in-hospital mortality was 0% vs 14.3% (both deaths after major bleeding) in low vs moderate intensity.

Clinical Implications

Pending confirmatory trials, centers may consider evaluating lower-intensity anticoagulation protocols to balance bleeding and thrombosis risks during vvECMO.

Limitations

• Small pilot sample, underpowered for clinical endpoints
• Open-label design and limited generalizability across ECMO practices

Future Directions

Conduct a large, adequately powered multicenter RCT to test clinical outcomes, including bleeding, thrombosis, circuit complications, and mortality, and to define anticoagulation targets.