Brain tumor patients undergoing craniotomy generally receive prophylaxis against venous thromboembolism (VTE), but modalities in use differ widely and have been debated in the literature. A systematic review and meta-analysis was conducted to assess the efficacy and safety of VTE prophylaxis among brain tumor patients undergoing craniotomy. Ten randomized controlled trials were included in the final efficacy analysis. The various prophylactic measures employed in these studies reduced the risk for thrombosis compared to controls with an overall risk ratio of 0.61 (95 % CI: 0.47-0.79) in the fixed effect model. Although Cochrane Q-test showed unimportant heterogeneity across studies (p = 0.19) and the I2, a measure of heterogeneity between studies, was reasonably low at 28 %, subgroup analysis indicated that intervention type was a potential effect modifier for efficacy (p = 0.04). Unfractionated heparin alone showed a stronger reduction in VTE risk compared to placebo (RR = 0.27; 95 % CI: 0.10-0.73), and LMWH combined with mechanical prophylaxis showed a lower VTE risk as compared to mechanical prophylaxis alone (0.61; 95 % CI: 0.46-0.82). This meta-analysis demonstrates a statistically significant VTE risk reduction among brain tumor patients receiving prophylaxis, with chemical prophylaxis showing the strongest risk reduction. Five studies were included in the safety analysis, which showed an overall increased risk of bleeding comparing different prophylactic measures to different controls (RR = 2.02; 95 % CI: 1.14-3.58; I2 = 0 %; p = 0.86). Interventions in these studies were associated with an increased risk of post-operative, minor hemorrhage (RR = 2.20; 95 % CI = 1.00; 4.85), while the risk of major hemorrhage was not increased by chemoprophylaxis.
Keywords: Brain tumor; Craniotomy; Heparin; Meta-analysis; Neurosurgery; Prophylaxis; Venous thromboembolism.