Intraoperative removal of subdural drains during surgery for chronic subdural hematoma does not increase recurrence compared with postoperative drainage

Background : Several reports suggest that using a subdural drain (SDD) for chronic subdural hematoma (CSDH) reduces recurrence rates. However, due to complications associated with SDD placement, we discontinued its use in initial surgeries. Methods : This study compared 150 historical cases with SDDs (SDD+ group) and 129 recent cases without SDDs (SDD- group). Results : Recurrence occurred in 18 patients (13.9%) in the SDD+ group and 12 patients (8.0%) in the SDD- group. The SDD- group had shorter operative times (40.9 vs. 54.9 min) and hospital stays (6.0 vs. 11.8 days). The overall complication rate was similar in both groups (4% vs. 1%), but the SDD+ group had serious complications related to SDD placement. Treatment costs were reduced by $811.8 per case in the SDD- group ($1978.2 vs. $1215.4). Preoperative hematoma thickness and subdural thickness on the first postoperative day were identified as independent recurrence factors, but no association was found with SDD use. Conclusions : Omitting SDD placement for CSDH did not increase the recurrence rate, shortened operative time and hospital stay, reduced costs, and minimized serious complications. By performing sufficient irrigation and reducing the residual air, it is possible that the recurrence rate will not increase even without inserting SDD, and we believe that this will serve as an opportunity to consider randomized controlled trials using a similar protocol in the future.