Coagulation abnormalities and bleeding in pregnancy: an anesthesiologist's perspective

ABSTRACT

During pregnancy, the procoagulant activity increases (manifested by elevation in factor VII, factor VIII, factor X, and fibrinogen levels), while the anticoagulant activity decreases (characterized by reduction in fibrinolysis and protein S activity), resulting in hypercoagulation. Standard coagulation tests, such as prothrombin time or activated partial thromboplastin time, are still used despite the lack of evidence supporting its accuracy in evaluating the coagulation status of pregnant women. Thromboelastography and rotational thromboelastometry, which are used to assess the function of platelets, soluble coagulation factors, fibrinogen, and fibrinolysis, can replace standard coagulation tests. Platelet count and function and the effect of anticoagulant treatment should be assessed to determine the risk of hematoma associated with regional anesthesia. Moreover, anesthesiologists should monitor patients for postpartum hemorrhage (PPH), and attention should be paid when performing rapid coagulation tests, transfusions, and prohemostatic pharmacotherapy. Transfusion of a high ratio of plasma and platelets to red blood cells (RBCs) showed high hemostasis success and low bleeding-related mortality rates in patients with severe trauma. However, the effects of high ratios of plasma and platelets and the ratio of plasma to RBCs and platelets to RBCs in the treatment of massive PPH were not established. Intravenous tranexamic acid should be administered immediately after the onset of postpartum bleeding. Pre-emptive treatment with fibrinogen for PPH is not effective in reducing bleeding. If fibrinogen levels of less than 2 g/L are identified, 2–4 g of fibrinogen or 5–10 ml/kg cryoprecipitate should be administered.