Antibiotic prophylaxis in endoscopic endonasal pituitary and skull base surgery

Objective: Postoperative infection is a potentially dramatic consequence in endoscopic endonasal surgery. The aim of this study is to assess the efficacy of our intraoperative antibiotic prophylaxis, analyzing the risk factors of postoperative meningitis in our series. Methods: Each endoscopic endonasal procedure performed since 1998 in patients with no preoperative infections and a follow-up longer than 30 days have been included and retrospectively reviewed. Antibiotic protocol consisted in single antibiotic administration of ampicillin/sulbactam 3 g or cefazolin 2 g on induction, no postoperative administrations have been performed after 2005. All cases of CSF leak, meningitis, and systemic infection were recorded. Results: Two thousand thirty-two procedures matched the inclusion criteria (median age 50; range: 1-89, male/female ratio: 1:1.12). Intraoperative CSF leak occurred in 32.8% of the cases and postoperative CSF leak in 3.4%. The rate of meningitis was 0.69%, other systemic infections were observed in 0.44% of cases. Meningitis was statistically associated with intra- and postoperative CSF leak (p<0.001). Other risk factors were the intradural extension of the tumors and their malignant histology. Extended approaches producing wide osteo-dural defects were correlated with a higher risk of meningitis (p<0.001). Conclusions: All surgical maneuvers to prevent, detect and quickly repair intra- and postoperative CSF leak are crucial to avoid postoperative meningitis. The proposed prophylaxis protocol is comparable in safety to those recommended in literature as assessed by the low rate of meningitis.