EVALUATION OF LOW-MOLECULAR-WEIGHT HEPARIN DURING AND AFTER AORTIC AND CAROTID SURGERY - DOSE-FINDING STUDY

Forty-four patients undergoing abdominal aortic surgery and twenty-eig ht patients undergoing carotid surgery were randomly treated with diff erent anticoagulant regimens. During surgery, an unfractionated hepari n (UFH) intravenous bolus of 50 IU/kg was compared with a low molecula r weight heparin (LMWH) bolus of either 120 IU/kg, 80 IU/kg, 40 IU/kg or 20 IU/kg. Six hours after surgery and for 48 hours, an UFH infusion was compared with an LMWH infusion of either 10,000 IU/day or 6,000 I U/day and then, a single LMWH subcutaneous injection of 3,075 IU was a dministered, Heparin activity was measured by factor Xa inhibitor and by prolongation of APTT which were studied 15, 30 and 60 minutes after cross-clamping, at the end of surgery and six hours later, and on day s 1, 2, 3 and 6, After a descriptive analysis of clinical and pharmaco kinetic profiles of each regimen, optimal LMWH treatment is proposed.