No correlation between lower extremity deep vein thrombosis and pulmonary embolism proportions in trauma: a systematic literature review.

PURPOSE: To assess the effect of surveillance on deep vein thrombosis (DVT) and pulmonary embolism (PE) rates, the efficacy of chemoprophylaxis and mechanical prophylaxis, and the relationship between DVT and PE.

METHODS: A 23 year, systematic literature review was performed in PubMed. Twenty publications with > 13,000 patients were reviewed. Analyzed traits included: DVT surveillance utilization, the total number of patients included in each study, the number of patients developing DVT and/or PE, chemoprophylaxis and mechanical prophylaxis utilization. When event proportions from individual studies were combined, a weighted mean proportion was computed based on the size of each individual cohort. Combined event proportions were compared with other combined event proportions, according to differences in intervention. Inter-group event proportions were compared using Chi-Square or Fisher's exact test, as appropriate.

RESULTS: DVT rates increase with surveillance (10.7% vs. 2.5%, p < 0.001). PE rates were similar regardless of surveillance (p = 1.0). Chemoprophylaxis lowered both DVT rates (8.2% vs. 10.7%; p < 0.0001) and PE rates (1.2% vs. 1.9%; p = 0.0050). Mechanical prophylaxis did not decrease DVT rates (10.2% vs. 11.5%; p = 0.2980) or PE rates (1.7% vs. 1.6%; p = 1.0). In patients with neither chemoprophylaxis nor mechanical prophylaxis, DVT rate was 11.5%, PE was 1.6%. When chemoprophylaxis and/or mechanical prophylaxis were given, DVT rate was 8.6% (p < 0.0189) and PE was 1.3% (p = 0.4462). PE proportions were not decreased with mechanical prophylaxis or surveillance. DVT and PE rates were not associated (p = 0.7574).

CONCLUSIONS: The results suggest that PE is not associated with lower extremity DVT in adult trauma patients.