Dose-response association of operative time and surgical site infection in neurosurgery patients: A systematic review and meta-analysis

Background The association of operative time and surgical site infection (SSI) in neurosurgery patients is unclear. We therefore, through a systematic review and meta-analysis, sought to clarify the association. Methods We performed a systematic search of the PubMed and Embase databases, from January 1, 1966, to December 26, 2018, for published articles. We used random effects generalized least squares regression models to combine study-specific relative risks (RR) and 95% confidence intervals (CI), and performed a sensitivity analysis by excluding 1 study at a time to assess the stability of results and potential sources of heterogeneity. We used the Egger (from plotting to test) to assess publication bias. Results A total of 5 articles, with 231,915 individuals and 6,726 SSI cases, were included. The summary RR for SSI after craniotomy were 1.67 (95% CI, 1.13-2.20), with high versus low operative time, and 1.34 (95% CI, 1.15-1.53), with each 1-hour increase in operative time. On sensitivity analysis, no individual study had an excessive influence on the pooled effect. We found no evidence of publication bias by the Egger test ( P  = .464) and Egger's plotting. Conclusions Prolonged operative time can increase the SSI risk for neurosurgery patients. Intensive interventions should be taken to decrease operative duration.