To assess the efficacy and safety of irrigation during burr hole drainage for chronic subdural hematoma.

The commonly used method for treatment of chronic subdural hematoma is burr hole craniotomy. However, the therapeutic effects of irrigation used during this method are still not well understood. 

PubMed, Cochrane Central, and ScienceDirect were searched till September 2024. The primary and secondary outcomes of interest were the recurrence rate of subdural hematoma, mortality, post-operative infections, hemorrhagic complications, and pneumocephalus. Risk ratios (RR) along with 95% CIs were calculated for categorical outcomes using the Review Manager Software 5.4.1 and employing a random effects model. The quality of the included studies was evaluated using the Newcastle Ottawa scale and Cochrane RoB 2.0 tool. A leave-one-out sensitivity analysis was performed to investigate the source of heterogeneity. The risk of publication bias was assessed through funnel plots and Eggers’s regression test.

Fourteen studies were included in the final analysis with a total of 2,251 patients. There was no significant difference in the recurrence rate of subdural hematoma (RR=1.01;95%CI: [0.64, 1.61]; p =0.95; I²=54%) and mortality (RR=1.13; 95%CI: [0.69, 1.84]; p =0.63; I²=0%) between the two groups. Similarly, no statistically significant difference was observed in the risk of postoperative infections (RR=0.87; 95%CI;[0.51, 1.47]; p=0.60; I²=0%), hemorrhagic complications (RR=1.35; 95%CI:[0.30, 6.05]; p=0.69; I²=63%) and pneumocephalus (RR=2.56; 95%CI:[0.95, 6.89]; p=0.06; I²=82%) between the irrigation and no irrigation groups.

In conclusion, burr hole craniotomy with or without irrigation shows comparable safety and efficacy outcomes. Further high-quality multicenter randomized clinical trials are required to confirm if irrigation has effects in improving the efficacy outcomes or reducing complications for better applicability in clinical practice.