RESUMO
OBJECTIVE: This prospective, randomized, single-center, open-label pilot study evaluated the safety and efficacy in carotid surgery of a single intraoperative bolus of body weight-adjusted enoxaparin compared with unfractionated heparin. METHODS: Symptomatic and asymptomatic patients with high-grade internal carotid artery stenosis were included. The primary objective was to evaluate perioperative efficacy (incidence of thromboembolic ischemic stroke). The secondary objective was to evaluate safety, including avoidance of hematoma at the site of surgery, gastrointestinal bleeding, rate of blood transfusions, and occurrence of heparin-induced thrombocytopenia. RESULTS: From July 2005 to June 2006, 338 consecutive patients undergoing carotid endarterectomy were enrolled; of these, 115 patients did not fulfill inclusion criteria, and 63 patients refused to participate. The remaining 160 patients were assigned in a 3:1 randomization to receive enoxaparin (0.5 mg/kg) or unfractionated heparin (5000 IU) intraoperatively as an intravenous bolus (120 and 40 patients, respectively). The mean patient age was 70.3 years (range, 43.3-94.7 years), and 54 were women. Internal carotid artery stenosis was asymptomatic in 55% and symptomatic in 45%. The difference in baseline characteristics between these groups was not significant. The rate of cerebral embolic events was 0.8% in the enoxaparin group (n = 1) and 2.5% in the unfractionated heparin group (n = 1). The rate of severe bleeding complications was 1.7% in the enoxaparin group (n = 2) and 5% in the unfractionated heparin group (n = 2; P > .05). No case of heparin-induced thrombocytopenia was observed. CONCLUSION: This pilot study found no difference between enoxaparin and unfractionated heparin during carotid endarterectomy in perioperative bleeding or embolic events. A large multicenter trial seems to be warranted.
