Renal Function and Volume Status in Patients with Morbid Obesity Undergoing Anterior Skull Base Surgery

Objectives: The purpose of this study is to examine the relationship between preoperative blood urea nitrogen (BUN), creatinine, and sodium in morbidly obese patients who underwent anterior skull base surgery and postoperative complication rates. We also investigate the association between morbid obesity and postoperative renal insufficiency in patients who underwent anterior skull base surgery.

Study Design: This is a retrospective database review.

Methods: The 2005 to 2015 National Surgical Quality Improvement Program (NSQIP) database was used to identify patients who underwent anterior skull base surgery. Propensity score matching (PSM) was conducted to homogenize the study population. Chi-squared analysis and logistic regression were used to determine the independent effect of covariates on postoperative complication rates.

Results: A total of 4,053 patients with known preoperative BUN, creatinine, and sodium levels who underwent anterior skull base surgery by neurosurgeons and otolaryngologists were identified. The patients were divided into two cohorts: morbidly obese (BMI ≥ 40 kg/m²; n = 318) and nonmorbidly obese (n = 3,735). Univariate analysis of this cohort indicated a significant association between morbid obesity and elevated preoperative creatinine (p = 0.029). There was not a significant association with elevated BUN (p = 0.491) or sodium level (p = 0.828). The morbidly obese patient cohort had significantly increased risk for postoperative renal insufficiency (p = 0.041) when compared with the nonmorbidly obese group. However, logistic regression modeling did not find a relationship between preoperative creatinine level and postoperative renal insufficiency in the morbidly obese patient cohort.

Conclusion: Following logistic regression, we found that morbid obesity in patients undergoing anterior skull base surgery was not significantly associated with elevated preoperative BUN, creatinine, and sodium levels. Although we found that morbid obesity was significantly associated with postoperative renal insufficiency on univariate analysis, this did not hold true on multivariate analysis.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
12 February 2021