Influence of Obesity and Fluid Balance on Operative Outcomes in Hepatic Resection

As the number of obese patients requiring hepatic resection is increasing, efforts to understand their operative risk and determine proper perioperative management are necessary. A total of 175 patients who underwent hepatic resection between March 2015 and July 2021 were evaluated. The patients were divided into two groups by their body mass index (BMI) using the World Health Organization definition of obesity for Asians: obese patients (BMI ≥ 25 kg/m2, n = 84) and non-obese patients (BMI < 25 kg/m2, n = 91). The operative duration (195.7 ± 62.9 min vs. 176.0 ± 53.6 min, p = 0.027) was longer and related to a higher estimated blood loss (EBL) ≥ 500 mL (61.9% vs. 40.7%, p = 0.005) in the obese patients than in the non-obese patients. Obesity (odds ratio (OR), 2.204; 95% confidence interval (CI), 1.177−4.129; p = 0.014) and central venous pressure (CVP) ≥ 5 (OR, 2.733; 95% CI, 1.445−5.170; p = 0.002) at the start of the surgery were significant risk factors for EBL ≥ 500 mL. Obese patients with low CVP showed significantly lower EBL than those with high CVP, but a similar EBL to non-obese patients (p = 0.003). In conclusion, fluid restriction before hepatic resection would be important, especially in obese patients, to improve their operative outcomes.