Excessive bleeding in cardiovascular surgery. Usefulness of viscoelastic coagulation tests

Abstract

Excessive bleeding due to coagulation disorders is a well-known complication in cardiovascular surgery. Traditionally, standard coagulation tests have been used for their management, and more recently, viscoelastic tests have gained ground. These are performed using a different methodology and provide information on clot initiation, firmness, and lysis. Viscoelastic tests can diagnose coagulation factor deficiencies, the presence of heparin and protamine, fibrinogen, fibrin or Factor XIII deficiencies, platelet deficiency, and hyperfibrinolysis. The correlation between them and standard coagulation tests is strong only in a few assays, and they have limitations in detecting the absence of coagulation general preconditions, platelet aggregation deficiency, von Willebrand factor deficiency, the effect of fractionated heparin, the effect of direct anti-Factor Xa anticoagulants and low and moderate intensity local or systemic fibrinolysis. To facilitate the treatment of patients with excessive bleeding, algorithms guided by viscoelastic testing have been designed.