Classical and Point-of-Care tests in severe hemorrhage management

Abstract

Hemorrhage is defined as an acute loss of blood from the cardiovascular system. The hemostatic cascade (comprising the vasculature, coagulation factors, the fibrinolytic and the platelet systems) is the physiological mechanism meant to control this event. Coagulation assessment is fundamental in the monitoring and treatment of hemorrhage. Over the years several classical laboratory-based diagnostic tests have been developed for the management of severe hemorrhage, however their main downside is the time necessary to obtain a result, which can be significant (between 40 minutes and an hour) and therefore not be entirely representative of a fastchanging clinical picture. Based on this need of faster results, Point-of-Care tests have been developed and implemented, since they can represent a diagnostic tool that allows a reduction of the time interval before appropriate intervention. They rely on instruments able to determine blood clot formation in whole blood samples upon activation of coagulation with specific reagents, and activation of platelets upon exposure to different drugs. The present review proposes an overview of both the available Point-of-Care tests such as Thrombelastography, for the assessment of blood clot formation, Impedance Aggregometry, for the function of platelets, and those still under improvement or missing entirely.