Abstract Number: Esoc2026a439 Optimizing Surgical and Perioperative Strategies in Chronic Subdural Hematoma: An Umbrella Review and Meta-Analytic Evidence to Guide Contemporary Practice

Background and aims Chronic subdural hematoma (CSDH) is among the most prevalent neurosurgical conditions in the elderly and remains associated with substantial morbidity, mortality, and recurrence rates despite surgical intervention. Considerable variation persists in operative and perioperative management. Methods We conducted an umbrella review of five systematic reviews and meta-analyses in accordance with PRISMA guidelines, comprehensively synthesizing evidence from PubMed, Scopus, Web of Science, Ovid, and Cochrane Library up to March 2024. A total of 12,263 patients were included. Comparative analyses evaluated the impact of drainage versus no drainage, irrigation versus no irrigation, anesthesia modality, postoperative head positioning, and drainage location on recurrence, mortality, complications, and functional outcomes. Results Drainage was consistently associated with significantly reduced recurrence (OR 0.39), mortality (OR 0.65), and focal neurological deficits (OR 0.58) compared with no drainage. Subperiosteal/subgaleal drainage demonstrated lower recurrence and postoperative brain injury rates compared with subdural drainage, without increasing mortality or infection. Local anesthesia was associated with fewer complications, shorter operative times, and reduced hospital stay compared with general anesthesia, with no difference in recurrence or mortality. Routine irrigation did not reduce recurrence and was linked to increased hemorrhagic complications in sensitivity analyses. Postoperative head positioning showed no significant effect on recurrence or reintervention rates. Conclusions This large-scale umbrella review provides robust, practice-informing evidence supporting routine drainage—preferably subperiosteal/subgaleal—under local anesthesia as an optimal strategy for CSDH management, while questioning the routine use of irrigation and restrictive postoperative positioning. These findings offer a pragmatic, evidence-based framework to standardize CSDH care and improve patient outcomes. Conflict of interest all authors have has nothing to disclose Table 1 - belongs to Results Table 2 - belongs to Results