Purpose: The aim of this study was to explore risk factors for intraoperative events and postoperative complications of endoscopic transsphenoidal surgery (ETS) for pituitary tumors, and the role of intrasellar pressure (ISP) in relation to complications.

Methods: The study was a single-center, retrospective, consecutive, observational study, with ISP data collected prospectively. After exclusions, the study population encompassed 69 patients. All had ISP measured intraoperatively during ETS for a pituitary adenoma and underwent standardized postoperative observations and follow-up. Data on complications within 3 months after surgery and some risk factors were collected retrospectively.

Results: Decreased risk of postoperative cerebrospinal fluid leakage was seen with higher age. Large tumor volume was associated with higher risk of intraoperative events. ISP was not associated with complication frequency, but patients with ISP > 20 mmHg had increased frequency of postoperative epistaxis.

Conclusion: This study confirms earlier findings of low age as a possible risk factor for postoperative cerebrospinal fluid leakage. Tumor volume is suggested to be associated with higher complication risk. ISP does not seem to be a significant risk factor for intraoperative events or postoperative complications following ETS. Predictive risk factors for surgical complications after ETS are still not satisfactorily explained and heterogeneous definitions of complications are problematic in this context.