Prospective study evaluating post-operative central nervous system infections following cranial surgery

To evaluate the efficacy of our methods for decreasing the incidence of post-operative central nervous system infections (PCNSI) and to assess the type of microbiology and risk factors associated with PCNSI.

This prospective study was performed at First Affiliated Hospital, College of Medicine, Zhejiang University, which is a major medical centre in eastern China. The study included adult patients who underwent cranial surgery from January 2014 to October 2015 at this institution and survived for more than 7 days . The demographic information and clinical data of the patients were recorded for every operation and the incidence of PCNSI and the type of microbiology were analysed separately for patients undergoing craniotomy and those undergoing cranial burr-hole surgery. Prior to initiation of the study, our research team had developed and implemented a series of methods for reducing infection rates in our department.

A total of 1,616 cranial surgery procedures were assessed in the present study; 1,236 craniotomy/craniectomy operations and 380 cranial burr-hole surgery operations. Of these procedures, 29 were complicated by PCNSI (27 cases with meningitis/ventriculitis and two with intracranial abscess/empyema). The overall incidence of PCNSI was 1.8%, while the incidence of craniotomy/craniectomy operations was 2.0% (25 cases) and that of burr-hole surgery operations was 1.1% (four cases); the most common microorganism was Staphylococcus. Of the patients who underwent cranial burr-hole surgery, the only independent risk factor for PCNSI was the absence of prophylactic antibiotics. There were no independent risk factors for craniotomy/craniectomy operations.

In the present large-sample study, the incidence of PCNSI was 1.8%, which was dramatically lower than that of a previous study performed by our research group.