Surgical Site Infections After External Ventricular Drain Placement: Incidence, Patient-Related, and Periprocedural...

External ventricular drain (EVD) placement is a routine neurosurgical procedure for cerebrospinal fluid (CSF) diversion. Despite standardized procedures, a considerable risk of infection remains. While CSF EVD-related infections (EVD-RI) are common and have been extensively studied, surgical site infections (SSI) as a distinct subset are, at least when compared with CSF EVD-RI, relatively rare and remain poorly understood in the context of EVD placement. Hence, the aim of this study was to determine the incidence and risk factors of SSI after EVD placement.

All consecutive adult patients undergoing EVD placement at a single neurosurgical center between January 2014 and April 2022 were included in this study. SSIs were defined according to the Centers for Disease Control and Prevention criteria for SSIs and were subsequently classified and managed in accordance with the institutional neurosurgical SSI guidelines. Patient-related and procedure-related factors were assessed for their role as independent predictors or confounders using a purposeful variable selection procedure, as proposed by Hosmer and Lemeshow.

A total of 384 patients (418 EVDs; 34 bilateral) were included in this study. The incidence of SSI was 2.9% per patient and 2.6% per catheter. Factors associated with a significantly higher risk of SSI after EVD placement included concurrent CSF EVD-RI (odds ratio [OR] = 40.50, 95% CI: 7.17-399.29; P < .001), obesity (OR = 21.40, 95% CI: 2.08-200.81, P = .006) and arteriovenous malformation (OR = 50.27, 95% CI: 3.06-1124.25, P = .007) as an indication for EVD placement, whereas angiography was associated with a significantly lower risk (OR = 0.073, 95% CI: 0.010-0.45, P = .005).

Postoperative SSI after EVD placement is a relatively rare, potentially preventable, and clinically and economically relevant complication. Both patient- and procedure-related factors influence SSI risk, with obesity and concurrent CSF EVD-RI emerging as strong predictors, highlighting the importance of meticulous perioperative management and vigilant postoperative surveillance, particularly in these risk groups.