Active Versus Passive Drainage Systems for Subdural Hematomas: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES:Chronic subdural hematoma (CSDH) management involves various surgical techniques, with drainage systems playing a pivotal role. While passive drainage (PD) and active drainage (AD) are both used, their efficacy remains contentious. Some studies favor PD for lower recurrence rates, while others suggest AD superiority. A systematic review and meta-analysis were conducted to address this controversy, aiming to provide clarity on optimal drainage modalities post-CSDH evacuation.METHODS:This systematic review and meta-analysis followed preferred reporting items for systematic reviews guidelines, searching PubMed, Embase, and Web of Science until February 2024. Inclusion criteria focused on studies comparing active vs PD for subdural hematomas. Data extraction involved independent researchers, and statistical analysis was conducted using R software. The assessment of risk of bias was performed using the Risk of Bias in Non-Randomized Studies of Interventions framework and the Risk Of Bias 2 tool.RESULTS:In this meta-analysis, involving 1949 patients with AD and 1346 with PD, no significant differences were observed in recurrence rates between the active (13.6%) and passive (16.4%) drainage groups (risk ratio [RR] = 0.87; 95% CI: 0.58-1.31). Similarly, for complications, infection, hemorrhage, and mortality, no significant disparities were found between the 2 drainage modalities. Complication rates were 7.5% for active and 12.6% for PD (RR = 0.74; 95% CI: 0.36-1.52). Infection rates were available for 635 patients of the active group, counting for 2% and 2.6%, respectively (RR = 0.98; 95% CI: 0.24-4.01). Hemorrhage rates were also available for 635 patients of the active group, counting for 1.1% and 2.2%, respectively (RR = 0.44; 95% CI: 0.11-1.81). Mortality rates were 2.7% and 2.5%, respectively (RR = 0.94; 95% CI: 0.61-1.46).CONCLUSION:Our study found no significant difference between passive and AD for managing complications, recurrence, infection, hemorrhage, or mortality in CSDH cases. Further large-scale randomized trials are needed for clarity.