Increased Operative Time for Benign Cranial Nerve Tumor Resection Correlates with Increased Morbidity Postoperatively

Background: Surveillance is the most relied upon method to evaluate factors that contribute to postoperative morbidity and mortality. Identifying factors that can be mitigated is the pinnacle of surgical quality improvement in efforts to optimize patient outcomes. Certain factors have previously been established in surgical populations as increasing risk for postoperative complications. These include age, anesthetic physical classification, and premorbid status and conditions. Operative time has previously been identified in the orthopedic, vascular, and spine surgery literature, but has not been reviewed in the setting of benign cranial tumors.

Methods: The American College of Surgeons’ National Surgical Quality Improvement Program (ACS-NSQIP) dataset was used for this retrospective cohort analysis. Patients were included for analysis if they were enrolled in the NSQIP data registry in the years 2007 to 2013 with a diagnosis code of a benign neoplasm of a cranial nerve. Primary outcomes including postoperative morbidity and mortality were analyzed as well as secondary outcomes of readmission and reoperation. The main co-variate of interest was operative time.

Results: A total of 565 patients were identified as having undergone surgical resection of a benign cranial nerve neoplasm. Mean (median) age for this patient population was 50.98 (53) years. Mean (median) operative time was 398 (370) minutes. The aggregate 30-day complication rate, readmission rate, and rate of return to the operating room were 9.9%, 9.9%, and 7.3%, respectively, on unadjusted analyses. CSF leak requiring reoperation or readmission occurred at a rate of 3.1%. Prolonged operations defined as operative time greater than the 75th percentile (413 minutes) were associated with an increased odds of overall complication (OR 3.96, 95% CI 1.95–8.02), return to the operating room (OR 2.62, 95% CI 1.22–5.62), and increased length of stay (1.5 days, 95% CI 0.89–2.20 days) on multivariable regression analysis controlling for available patient and operative characteristics. When assessed as a continuous variable in a risk-adjusted manner, each additional minute of operative time was associated with an increased odds of overall complication (OR 1.004, 95% cI 1.002–1.006) and length of stay (0.006 days, 95% CI 0.004–0.008).

Conclusions: Patients undergoing surgical resection of a benign cranial neoplasm demonstrated increased rate of complications postoperatively with lengthened procedure times. This data emphasizes the need for the surgical team to remain cognizant of the length of the operation and minimize delays in the operating room.