Standard-dose unfractionated heparin versus low-dose unfractionated heparin and low-molecular-weight heparin in extracorporeal life support (RATE): an open-label, randomised, non-inferiority trial.

Summary

In this three-arm, multicenter RCT of ECMO patients, both low-dose UFH and therapeutic LMWH were non-inferior to standard-dose UFH for a composite of severe bleeding, severe thromboembolic events, or 6‑month all-cause mortality. Lower-intensity strategies showed numerically fewer severe bleeding events without excess thromboembolism.

Key Findings

• Both low-dose UFH and therapeutic LMWH met non-inferiority versus standard-dose UFH for the composite of severe bleeding, severe thromboembolism, or 6‑month mortality.
• Numerically fewer severe bleeding events occurred with low-dose UFH and LMWH compared with standard-dose UFH, without increases in severe thromboembolism.
• At 6 months, mortality rates were similar across arms (50% standard UFH vs 42% low-dose UFH vs 44% LMWH).

Clinical Implications

ECMO protocols can safely consider lower-intensity anticoagulation (low-dose UFH or therapeutic LMWH) to mitigate bleeding risk while maintaining thromboembolic protection, pending local implementation and monitoring.

Limitations

• Open-label design may introduce performance bias
• Conducted in Dutch ICUs; generalizability to other settings and VV vs VA ECMO subgroups warrants confirmation

Future Directions

Confirm findings in broader international cohorts, evaluate patient-centered bleeding outcomes, and refine anticoagulation targets by ECMO mode, indication, and concurrent therapies.