Meta-analysis and systematic review of randomized controlled trials assessing the role of thromboprophylaxis after vascular surgery

Background: Venous thromboembolism (VTE) is a well-known complication associated with surgical procedures. The implementation of thromboprophylaxis in this population has become a vital aspect of perioperative care to decrease VTE-associated morbidity and mortality risk. However, data assessing the role of thromboprophylaxis for patients undergoing vascular surgery are sparse. Assessing the role of thromboprophylaxis by low-molecular-weight heparin or unfractionated heparin in vascular surgery. Methods: We searched MEDLINE, Embase, and the Cochrane Collaboration Central Register of Controlled Trials from inception until December 2020, for randomized controlled trials assessing the role of thromboprophylaxis in vascular surgery. Results: Eight randomized controlled trials met inclusion criteria, including 3130 patients, with a mean age of 55.35 years and 45% were females. Compared with placebo, anticoagulant use was associated with a decrease in deep venous thrombosis (DVT) (risk ratio [RR], 0.34; 95% confidence interval [CI], 0.11-1.05; P = .06; I-2 = 68%) and pulmonary embolism (PE) (RR, 0.17; 95% CI, 0.02-1.22; P = .08; I-2 = 41%), but this trend did not attain statistical significance. There was no difference for bleeding outcomes between anticoagulants and placebo (RR, 0.90; 95% CI, 0.05-15.01; P = .94; I-2 = 76%). There was no significant difference in outcomes when low-molecular-weight heparin was compared directly with unfractionated heparin. In a sensitivity analysis, anticoagulant use was associated with a significant decrease in DVT or PE in patients undergoing venous surgeries, but was not associated with a significant decrease in DVT or PE in patients undergoing arterial surgeries, although this analysis was limited by the small number of studies in each group. Conclusions: Among patients undergoing vascular surgery, thromboprophylaxis with anticoagulants showed a trend toward a lesser incidence of VTE when compared with placebo, although this difference was not statistically significant. Bleeding outcomes were comparable between both treatment groups.