Unexpected hemorrhage in surgery.

Unexpected hemorrhage in surgery may be avoided whenever preoperative examinations have not detected a defect of hemostasis. A prospective study conducted before oral surgery demonstrated that a simple preoperative screening program was suitable for specific detection of patients with bleeding tendencies and to indicate the need for a more detailed evaluation of hemostasis. The screening program includes a detailed history with the aim of detecting congenital defects of hemostasis or bleeding tendencies due to prolonged, acquired disorders. The thromboplastin time (Quick test) should be performed to evaluate asymptomatic, acquired coagulation defects, especially liver disease, whereas the semiquantitative determination of platelets on blood smears is necessary to rule out thrombocytopenia. A dramatic complication of massive bleeding is the so-called "dilution syndrome" caused by simultaneous blood loss and transfusion of stored blood (or red cells alone), leading to a progressive reduction of clotting factors and platelets. Therapeutic and organizational measures which are necessary in this exceptional situation are briefly discussed.