title: A comparison of low-dose heparin with low-molecular-weight heparin as prophylaxis against venous thromboembolism after major trauma.
abstract: BACKGROUND
  Patients who have had major trauma are at very high risk for venous thromboembolism if they do not receive thromboprophylaxis. We compared low-dose heparin and a low-molecular-weight heparin with regard to efficacy and safety in a randomized clinical trial in patients with trauma.
  
  
  METHODS
  Consecutive adult patients admitted to a trauma center who had Injury Severity Scores of at least 9 and no intracranial bleeding were randomly assigned to heparin (5000 units) or enoxaprin (30 mg), each given subcutaneously every 12 hours in a double-blind manner, beginning within 36 hours after the injury. The primary outcome was deep-vein thrombosis as assessed by contrast venography performed on or before day 14 after randomization.
  
  
  RESULTS
  Among 344 randomized patients, 136 who received low-dose heparin and 129 who received enoxaparin had venograms adequate for analysis. Sixty patients given heparin (44 percent) and 40 patients given enoxaparin (31 percent) had deep-vein thrombosis (P=0.014). The rates of proximal-vein thrombosis were 15 percent and 6 percent, respectively (P=0.012). The reductions in risk with enoxaparin as compared with heparin were 30 percent (95 percent confidence interval, 4 to 50 percent) for all deep-vein thrombosis and 58 percent (95 percent confidence interval, 12 to 87 percent) for proximal-vein thrombosis. Only six patients (1.7 percent) had major bleeding (one in the heparin group and five in the enoxaparin group, P=0.12).
  
  
  CONCLUSIONS
  Low-molecular-weight heparin was more effective than low-dose heparin in preventing venous thromboembolism after major trauma. Both interventions were safe.
authors.affiliation: Department of Medicine, Sunnybrook Health Science Centre, University of Toronto, ON, Canada.
authors.forename: W H
authors.initials: WH
authors.lastname: Geerts
authors.forename: R M
authors.initials: RM
authors.lastname: Jay
authors.forename: K I
authors.initials: KI
authors.lastname: Code
authors.forename: E
authors.initials: E
authors.lastname: Chen
authors.forename: J P
authors.initials: JP
authors.lastname: Szalai
authors.forename: E A
authors.initials: EA
authors.lastname: Saibil
authors.forename: P A
authors.initials: PA
authors.lastname: Hamilton
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D006493:Heparin / Q000008:administration & dosage*; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D010690:Phlebography; D011655:Pulmonary Embolism / Q000209:etiology / Q000517:prevention & control; D012306:Risk; D013923:Thromboembolism / Q000517:prevention & control*; D013924:Thrombophlebitis / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control; D016896:Treatment Outcome; D014947:Wounds and Injuries / Q000150:complications
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight; D006493:Heparin