Anticoagulation Monitoring Strategies During Extracorporeal Membrane Oxygenation (ECMO) Therapy - Differences Between...

Area of Science:

• Critical Care Medicine
• Hematology
• Cardiovascular Surgery

Background:

• Extracorporeal membrane oxygenation (ECMO) requires systemic anticoagulation, typically with unfractionated heparin (UFH).
• Optimal monitoring of UFH anticoagulation during ECMO remains uncertain, posing risks for bleeding and thrombosis.

Purpose of the Study:

• To evaluate the correlation and concordance of R-time (thromboelastography), activated partial thromboplastin time (aPTT), and anti-Xa activity in ECMO patients.
• To assess the association of coagulation parameters with mortality, bleeding, and thrombotic complications.

Main Methods:

• Retrospective analysis of 85 venovenous and venoarterial ECMO cases at the Medical University of Graz.
• Analysis of 671 simultaneous coagulation test results (R-time, aPTT, anti-Xa activity).
• Investigation of the proportion of tests within target ranges and their correlation with clinical outcomes.

Main Results:

• High discordance (46%) and poor correlation were observed between R-time, aPTT, and anti-Xa activity.
• Therapeutic ranges were achieved by only 21% (R-time), 15% (aPTT), and 44% (anti-Xa activity) of measurements.
• Elevated anti-Xa activity in VA-ECMO was associated with increased bleeding events; lower aPTT was linked to reduced mortality.

Conclusions:

• Current coagulation monitoring tests (aPTT, anti-Xa, R-time) demonstrate significant discordance in ECMO patients.
• Bleeding events are frequent, with elevated anti-Xa activity being a risk factor in VA-ECMO.
• Further research is needed to establish reliable anticoagulation monitoring strategies for ECMO.