RESUMO
BACKGROUND: The high incidence of deep vein thrombosis (DVT) of lower extremities and a subsequent pulmonary embolism (PE) makes it the most common cause of death following total hip replacement surgery. Therefore, the authors measured the perioperative changes in the blood coagulation activity with a thromboelastography (TEG) in the patients treated with fluid and packed red cells (PRC). METHODS: Hemodilution was estimated with a measurement of hemoglobin (Hb), hematocrit (Hct), and platelet count. The changes in the coagulation factor activities were measured with TEG. Samples were obtained before skin incision (step 1); at the period that Hb and Hct ranged from about 10 g/dl to 30% (step 2); in the postanesthetic care unit (step 3); and on the postoperative first and third day (step 4, 5). RESULTS: Although Hct and Hb decreased to 9.4% statistically at step 2 only, platelet counts were significantly decreased in step 2 (10.6%), 3 (34.5%), 4 (32.5%), and 5 (33.6%) compared with step 1 (P < 0.05). At step 2, there were no significant changes in TEG parameters except r time, which decreased (21.5%) (P < 0.05). At step 3, r time, alpha angle, and maximum amplitude (MA) decreased, and k time and lysis 60 increased (P < 0.05). CONCLUSIONS: In spite of consumption and dilution of coagulation factors after massive fluids and PRC therapy during total hip replacement surgery, the increased activities of procoagulants and decreased fibrinolytic activities predisposed the body to initiate and maintain the thrombus.