Effect of Body Mass Index on Intraoperative Complications During Hepatic Resection for Malignancy

Evidence shows that high body mass index (BMI) contributes to increased postoperative complications in gastrointestinal surgery and suggests that it may contribute to intraoperative adverse events. We primarily aimed to determine if high BMI results in increased intraoperative adverse events in liver resections using the ClassIntra classification.

A retrospective audit of liver resections under a single adult Hepatobiliary unit was performed from February 2018 to October 2023. We compared intraoperative adverse events and postoperative complications between BMI groups ('Normal/low' BMI < 25, 'Overweight' BMI 25-30 and Obese > 30). Resections were divided by complexity into minor, intermediate and major resections by extent of liver resection.

One hundred and ninety-nine patients were included in the analyses. Higher BMI was associated with a significantly greater proportion of intraoperative complications using the ClassIntra classification (p = 0.022). At least one intraoperative complication was sustained by 33.3% and 38.2% of overweight and obese patients, respectively, compared to 19.1% in normal/low weight individuals. There were no differences in other intraoperative or postoperative outcomes or complications with a higher BMI, including estimated blood loss, morbidity by Clavien-Dindo classification, 30-day readmission or mortality. Multivariate analysis showed that BMI class and diabetes status were significantly related to higher ClassIntra complication level (p = 0.0086).

Higher BMI is associated with increased rates of intraoperative adverse events during liver resection surgery, by measure of ClassIntra classification. Prospective standardised assessment of intraoperative complications is required to confirm these findings.