ABSTRACT
Point-of-care coagulation devices providing bedside activated clotting times (ACT) for monitoring unfractionated heparin administration have been in use for several decades. This chapter describes the complexities of ACT measurement and presents a detailed scenario for good laboratory practice in establishing a reliable ACT monitoring service. In the absence of universal ACT test standardization, and with varied combinations of reagents and technologies among different instruments, ACT results vary between manufacturer and model instrument. Considering that target times need to be developed by each facility according to its own patient population, heparin protocol and specific ACT test systems, the information presented herein is a valuable guide for establishing laboratory protocols relating to instrument selection, policy procedures, personnel training, for documenting quality control, and for standardizing system baseline ACT values and normal ranges using precision and correlation methods.
