Base Excess as a Predictor of Complications in Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy

Base excess is important in assessing metabolic status. Postoperative management in patients undergoing cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal malignancies can be a challenge, and we therefore sought to investigate perioperative predictors of overall morbidity in CRS/HIPEC patients at our institution.

Patients who underwent CRS/HIPEC from 2012 to 2016 were identified retrospectively from a prospectively collected institutional database. Patient demographics and perioperative variables were obtained and the comprehensive complication index (CCI) was calculated for each patient in order to assess perioperative morbidity. Stepwise linear regression analyses were performed, with CCI as the outcome variable.

A total of 72 CRS/HIPEC patients had recorded base excesses in the first 48 h postoperatively. Mean immediate postoperative base excess was -6.0 mmol/L (interquartile range [IQR] -8 to -4.1), mean delta base excess at 48 h was +4.3 mmol/L (IQR +2.1 to +6.2), and mean CCI was 25.2 (IQR 8.7-36.7). On multivariate analysis, delta base excess was the only significant predictor of CCI, demonstrating a protective effect (p = 0.001). In patients who experienced less than the mean delta base excess of +4.3 mmol/L, lower delta base excess was an independent predictor of complications (p < 0.001).

Delta base excess is an independent predictor of morbidity in patients undergoing CRS/HIPEC. A delta base excess of greater than +4.3 mmol/L at 48 h may be an appropriate goal for resuscitation of CRS/HIPEC patients in the immediate postoperative period. Standardized protocols to correct the base deficit in CRS/HIPEC patients during the early postoperative period can potentially help mitigate perioperative morbidity.