Results of an international survey on the management of therapeutic intensity unfractionated heparin: communication from the SSCs of the ISTH.

BACKGROUND: Unfractionated heparin (UFH) remains the anticoagulant of choice in critically ill patients. However, its laboratory monitoring and clinical management are particularly challenging. OBJECTIVES: Our objective was to describe current practices and variations among centers of the ISTH. METHODS: Between November 2023 and February 2024, we surveyed 142 clinicians and laboratory medicine specialists from 15 countries involved in the care of patients receiving therapeutic-intensity UFH. RESULTS: UFH monitoring was based on an anti-Xa assay or on activated partial thromboplastin time in 54% and 46% of respondents, respectively. Different therapeutic ranges were used depending on local protocols and indications; the 0.3 to 0.7 IU/mL anti-Xa range was commonly used, except for patients on mechanical circulatory support with a lower range, mostly 0.3 to 0.5 IU/mL. Most respondents managed therapeutic UFH administration with weight-based dosing (88%), while fewer used a nomogram (57%) for dose adjustment. When a nomogram was used, it was primarily based on anti-Xa monitoring (86%). The situations when respondents administered antithrombin varied widely; 22% reported using it when antithrombin levels were below 60 IU/dL(%) and 20% reported never using it. CONCLUSION: Our survey results revealed considerable heterogeneity in UFH management approaches, reflecting a knowledge gap and a paucity of evidence to guide decision-making. Key issues requiring well-designed up-to-date studies were identified that include optimal approaches to heparin monitoring, assays and reagents to be used, therapeutic range based on indications, the use of weight-adjusted nomograms for initial dosing and titrating of UFH infusion, and indications for antithrombin supplementation. Survey results provide a strong rationale for the development of international guidance addressing these issues.

Duke Scholars

Author Jerrold Henry Levy Anesthesiology, Cardiothoracic