Introduction: Surgical site infection (SSI) can be a significant cause of patient morbidity and mortality after cranial surgery.
Methods: We analyzed administrative data (2003-2010) for patients undergoing cranial neurosurgery at two university-associated hospitals. Patients (“cases”) who were readmitted with a diagnosis of infection or who underwent surgical re-exploration for infection were identified. Control patients were then randomly identified matched for index operation CPT code and by year. Chart review was performed of case and control patients. Logistic regression was used to perform univariate and multivariate analysis to identify risk factors associated with SSI.
Results: 9,191 cranial neurosurgery cases were performed and 209 infections were identified (2.3%). Within the administrative dataset, multivariate analysis found functional (OR 2.6, 95% CI: 1.8 – 3.7, p<0.0001) and CSF diversion (OR 1.7, 95% CI: 1.2 – 2.5, p=0.005) procedures were associated with increased risk of SSI. Redo procedures were not associated with increased SSI risk.
Comparing the cases and controls (n=209 in each group, matched on procedure subtype) any smoking history, redo surgery, and length of stay were associated with increased risk of infection on univariate analysis. Age, gender, obesity, diabetes, use of a surgical drain, operative time, prior radiation therapy to site, and use of high alcohol prep were not associated with SSI risk. On multivariate analysis smoking (OR 1.7, 95%CI: 1.1 – 2.6, p=0.015), redo surgery (OR 2.2, 95%CI: 1.3 – 3.5, p=0.002), and length of stay (OR 1.02, 95%CI: 1.01 – 1.04, p=0.004) were associated with increased SSI risk.
Conclusions: Though SSI risk varied by surgery type, the primary controllable risks for SSI after cranial surgery in our analysis were smoking and length of stay. Even adjusting for other factors, use of high alcohol prep (e.g. chloraprep) was not associated with reduced SSI rates.
Patient Care: : This large single-center study identifies some risk factors which may be worth focusing on to further reduce SSI rates. It also challenges the existing literature on the benefits of chlorhexidine alcohol surgical prep over povidone iodine
Learning Objectives: by the conclusion of this session, participants should be able to Identify modifiable and non-modifiable risk factors for surgical site infections in cranial surgery.