Influence of anthropometric factors on estimating intraoperative challenges in bariatric surgery: a prospective correlational study

INTRODUCTION: Laparoscopic sleeve gastrectomy (SG) is a widely performed bariatric procedure that trainee surgeons are increasingly performing. While body mass index (BMI) is commonly used to predict surgical challenges, its limitations necessitate exploring alternative anthropometric factors. This study examines the role of additional anthropometric factors in predicting intraoperative difficulty, with the goal of improving surgical planning and outcomes. METHODS: A prospective cohort study included 100 SG patients treated between January and July 2023 at a tertiary bariatric center. Preoperative assessments included anthropometric measurements, ultrasound evaluation of abdominal fat, and bioelectrical impedance analysis. Intraoperative difficulty was assessed using two measures: deviation of operative time from each surgeon's mean operating time and a standardized 13-item surgeon questionnaire rating the technical difficulty of specific surgical steps. Potential predictors, including patient characteristics, anthropometric indices, and surgeon experience, were analyzed using univariate and multivariable regression models, with collinearity checks to ensure model validity. RESULTS: The mean BMI was 43.6 ± 5.6 kg/m², the median visceral fat rating (VFR) was 15.0 [IQR 12.00-21.00], and the mean waist-hip ratio (WHR) was 0.92 ± 0.10. Surgical specialists performed 75% of procedures, with a median operating time of 50 min, compared to 90 min for residents. Surgeons' questionnaire responses indicated overall low perceived technical difficulty, with median scores ranging from 1.00 to 2.00 across all surgical steps. In multivariable regression analysis, higher BMI, VFR, WHR, and waist circumference were significant independent predictors of longer operative times after adjusting for confounders. Regression model including BMI showed the strongest association with increased surgical difficulty, explaining up to 21% of the variance (adjusted R² = 0.214). CONCLUSION: Higher BMI, VFR, WHR, and waist circumference were independently associated with increased intraoperative difficulty during sleeve gastrectomy, with BMI emerging as the strongest predictor.