EFFICACY OF SUBCUTANEOUS HEPARIN IN PREVENTION OF VENOUS THROMBOEMBOLIC EVENTS IN TRAUMA PATIENTS

Trauma patients have an incidence of deep venous thrombosis (DVT) of 7 % to 65%. Conflicting data exists regarding the impact of prophylactic anticoagulant therapy. The purpose of this study is to assess the eff icacy of DVT prophylaxis based upon our data and a meta-analysis of th e current literature. Literature review revealed five recent studies t hat met the following criteria: 1) Adult patients sustaining major tra uma (injury severity store (ISS) > 10), 2) prospective surveillance fo r DVT using lower extremity duplex examinations, 3) clear documentatio n of method of DVT prophylaxis with particular attention to the use of anticoagulation and the corresponding incidence of DVT or pulmonary e mbolus (PE). Additionally, 66 trauma patients in our intensive care un it were prospectively identified and followed with duplex examinations . Patients received either anticoagulation DVT prophylaxis or pneumati c compression boots. An unpaired Student t test was used to compare th e characteristics of patients with and without DVT. A Mantel-Haenszel chi-square meta-analysis was performed on the five recent studies and our own data to compare the incidence of DVT/PE in patients with and w ithout anticoagulation. Meta-analysis of the literature included 1102 patients and demonstrated no benefit from anticoagulation for DVT prop hylaxis in trauma patients (10% DVT/PE with anticoagulation versus 7 p er cent DVT/PE without anticoagulation, P = 0.771). Our own population had a mean age of 38 +/- 17 years, ISS of 29 +/- 11 and a length of s tay (LOS) of 34 +/- 22 days. Sixteen events occurred with 13 (20%) DVT s and three (4%) pulmonary emboli. Age, ISS, type of injury, and the u se of pneumatic compression boots (PCB) or anticoagulants were not ris k factors for DVT/PE. Fifty-five (83%) of the 66 patients in our study group were at increased risk for VTE because of head injuries, spinal cord injuries, femur fractures, or pelvic fractures. In this group, i ncreased age (47 +/- 21 years versus 33 +/- 15 years P < 0.009) and in creased LOS (47 +/- 28 days versus 27 +/- 14 days P < 0.02) were risk factors for VTE. Among high risk trauma patients, increased age and LO S are risk factors for DVT that are not altered with prophylaxis of an y form.