Unfractionated heparin: optimizing laboratory monitoring and reducing unwanted interference in everyday hemostasis test practice

Unfractionated heparin (UFH) serves as a commonly used anticoagulant. It is widely utilized for a variety of reasons, including to 1) anticoagulate patients and help treat and / or prevent thrombosis, 2) maintain patency in artificial blood flow circuits, and 3) anticoagulate blood samples collected for laboratory testing (typically for biochemical assays or blood gas analysis). As such, the presence of UFH is nearly ubiquitous in a hospital setting. Therefore, in laboratory practice, UFH may be present in samples intended for monitoring patients on UFH therapy or intended for biochemical tests, or it may interfere with other (hemostasis) laboratory tests. The aim of this manuscript is to review the role of UFH from the perspective of optimizing laboratory testing to monitor UFH therapy and to avoid or overcome unwanted interference with other laboratory tests.