Incidence, depth, and severity of surgical site infections after neurosurgical interventions

Today, there are only few reports on the incidence of surgical site infections (SSIs) in neurosurgery. The objective of this work was to determine the rate of SSI at a tertiary neurosurgical department for benchmarking purpose.

Data of consecutive patients undergoing neurosurgical treatment between January 2013 and December 2016 were prospectively entered into a registry. SSIs were diagnosed according to the 2017 Centers for Disease Control and Prevention criteria, with severity graded according to the Clavien-Dindo grade (CDG). We analyzed type and length of surgery (LOS), time to SSI, responsible microorganisms, and its association with the functional status (Karnofsky Performance Status = KPS).

Of n = 5463 procedures, a SSI occurred in n = 106 (1.94%). The highest rates of SSI occurred after vascular (3.4%) and cerebrospinal fluid (CSF) diversion procedures (3%), as well as after procedures performed to treat a previous complication (2.9%). There was no difference in LOS across procedures with and without SSI. The median time between the index procedure and SSI was 15.5 days. SSIs were most frequently diagnosed after hospital discharge (55%). The most common microorganisms were coagulase-negative staphylococci, Staphylococcus aureus, and Escherichia coli. In 62.3% of cases, SSI required invasive treatment (surgical revision). Patients with SSI in the in- and out-patient setting (SSI occurring after hospital discharge) presented both with a median KPS of 80.

The current report provides an overview on SSI in a contemporary, unselected, large series of patients undergoing modern neurosurgical care for benchmarking purposes. The overall rate of SSI was about 2%, but subpopulations with higher risks were identified where additional measures could be taken to prevent SSI and monitor patients at risk more closely for SSI.