Irrigation practices in surgical evacuation of chronic subdural hematoma: systematic review and meta-analysis of technique, fluid type, and temperature
摘要
Chronic subdural hematoma (CSDH) frequently recurs after burr-hole craniostomy with drainage. The role of intraoperative irrigation—whether to irrigate at all, and the optimal fluid, temperature, and volume—remains uncertain. We aimed to synthesise contemporary comparative evidence. MEDLINE, Embase, and Scopus were searched to 14 October 2024; ClinicalTrials.gov and grey literature (conference abstracts, theses/dissertations) were also searched. Screening and risk-of-bias assessment were performed in duplicate. The primary outcome was reoperation for recurrence; mortality and overall complications were secondary outcomes. Random-effects meta-analyses pooled two prespecified comparisons: irrigation versus no irrigation and artificial cerebrospinal fluid (aCSF) versus saline. Heterogeneity (I²/τ²) and small-study effects (Egger’s test where k ≥ 10) were examined, with fixed-effects models as sensitivity analyses. Irrigation temperature and volume were summarised narratively because of heterogeneous protocols. Fifty-six studies were included. Across 29 comparisons (n = 4,042), irrigation did not clearly reduce reoperation versus no irrigation (RR 0.89, 95% CI 0.70–1.14; I² = 25%; low-certainty evidence). Mortality and complications were similar (moderate-certainty evidence). A large multicentre non‑inferiority RCT failed to demonstrate that omitting irrigation lay within the prespecified margin (7.5%); its point estimate favoured irrigation. Among studies using irrigation, warmed fluid (~ 37 °C) was associated with lower recurrence than room-temperature irrigation (~ 22 °C; 6% vs. 14%), without safety concerns (moderate-certainty evidence). For fluid composition, pooled estimates suggested a possible advantage of aCSF over saline (random-effects RR 0.60, 95% CI 0.35–1.03; I² = 58%; low-certainty evidence), but results included a neutral multicentre RCT. Irrigation volume showed no adjusted association with recurrence. Intraoperative irrigation during burr-hole craniostomy of CSDH offers no confirmed overall reduction in recurrence, complications, or mortality, but warmed (~ 37 °C) irrigation appears beneficial and carries minimal risk. Evidence for the influence of irrigation fluid type and volume remains uncertain and low in certainty. Registration: PROSPERO CRD42024595146.