Heparin prophylaxis for deep venous thrombosis in a patient with multiple injuries: an evidence-based approach to a clinical problem.

OBJECTIVE: To demonstrate a clinical decision-making process by which to determine if heparin prophylaxis for deep venous thrombosis (DVT) is appropriate in a specific patient with multiple injuries. DATA SOURCES: A Medline search of the literature. Search terms included trauma, heparin, deep venous thrombosis, thrombophlebitis, phlebitis, and trauma. STUDY SELECTION: Eleven studies were selected from 789 publications using published criteria. Incidence, risk and potential for prophylaxis were established through a structured review process. DATA EXTRACTION: After the structured review, a small number of studies were available for the consideration of incidence (2), natural history (4) and prophylactic therapy (2). DATA SYNTHESIS: The incidence of DVT in a patient with such multiple injuries is significant (58%-63%). The resulting risk of pulmonary embolism was 4.3% with an associated 20% death rate. Prophylaxis with low molecular weight heparin is associated with a statistically and clinically significant risk reduction for DVT when compared with unfractionated heparin and untreated controls.
CONCLUSIONS: Few of the multiple available studies concerning trauma, DVT and pulmonary embolism meet reasonable standards to establish clinical validity. Available guidelines for literature evaluation allow surgeons to select relevant articles for consideration. Patients with multiple trauma appear to be at significant risk for DVT. The death rate associated with subsequent pulmonary embolism is significant. There is reasonably good evidence to suggest that low molecular weight heparin will reduce this likelihood without a significant risk of treatment complications.