Abstract
Aims: In a prospective, randomized, single, general surgery center trial, comparison of the safety and efficacy of two low molecular weight heparin (LMWH; anti-Xa heparin sodium and weight-adapted nadroparin calcium) regimens was made. Patients and Methods: Eleven hundred and ninety patients undergoing various elective and emergency operations were randomized to receive daily either a fixed dose of 3,000 IU anti-Xa heparin sodium or a variable body weight-dependent dose of nadroparin calcium (weight <50 kg, 2,050 IU anti-Xa (WHO); 51–80 kg, 3,075 UI; 81–100 kg, 4,100 UI, and >100 kg, 6,150 UI) once until discharge. The first injection was administered 2.5–6 h before elective and emergency operations, respectively. Patients with clinical suspicion of deep venous thrombosis (DVT) underwent phlebography. Patients with signs of pulmonary embolism (PE) were further investigated by a ventilation-perfusion scan. Results: Statistically, there were no significant differences in the incidence of clinically evident DVT, PE or LMWH-related complications between both prophylactic regimens. Only 4 of the total of 15 hemorrhagic complications (4 wound hematomas in the nadroparin calcium group) were not classified as clearly surgically related, Two DVTs were confirmed by phlebography (both in the nadroparin calcium group). PE was confirmed by ventilation-perfusion scans (1 fatal, 1 on autopsy) in 1 patient with heparin sodium and in 6 patients with nadroparin calcium. Conclusions: Both regimens were equally safe and the risk of clinically evident DVT and PE was similar.