Association of High BMI With Morbidity and Mortality in Common Emergency General Surgery Procedures

Introduction: Emergency general surgery (EGS) patients are at increased risk for postoperative morbidity and mortality. Obesity is a risk factor for poor outcomes in this population. Our study aimed to explore the association of body mass index (BMI) with postoperative outcomes in patients requiring common EGS procedures.

Methods: A retrospective review of the 2018-2020 National Surgical Quality Improvement Program database identified patients undergoing four common EGS procedures: large bowel resection, small bowel resection, cholecystectomy, and appendectomy. Patients were classified by BMI: normal weight (18.5-24.9 kg/m²), obesity classes I (30-34.9 kg/m²), II (35-39.9 kg/m²), III (40-49.9 kg/m²), and IV (≥50 kg/m²). Main outcomes of interest were major adverse event (MAE) and mortality.

Results: From 2018 to 2020, a total of 82,540 patients underwent one of four common EGS procedures. On unadjusted analysis, obesity class IV had higher mortality rates compared to classes I-III (6.2% vs 3.1%, P < 0.001). Patients in obesity classes I-III had lower odds of MAE and death relative to those of normal weight. Compared to other patients with obesity, those in obesity class IV were at increased risk of MAE (odds ratio 1.27; 95% confidence interval 1.13-1.44) and death (odds ratio 1.69; 95% confidence interval 1.34-2.13).

Conclusions: Patients with varying degrees of obesity have different risk profiles following common EGS procedures. While patients in lower obesity classes had reduced odds of adverse outcomes, those with BMI ≥50 kg/m² were particularly at greater risk for postoperative morbidity and mortality. This vulnerable population warrants further investigation and increased vigilance to ensure high-quality care.