Simple Measurement of Intra-abdominal Fat for Abdominal Surgery Outcome Prediction

Objective: To assess the effect of increasing body mass index, intra-abdominal fat, and outer abdominal fat on outcome in patients undergoing major hepatectomy. Design: Cohort study. Setting: Memorial Sloan-Kettering Cancer Center. Participants: We studied patients aged 19 to 86 years undergoing major hepatic resection between June 18, 1996, and November 6, 2001. Complications were extracted from a prospective database at a tertiary cancer center. Intervention: A total of 349 patients were grouped according to body mass index for analysis. Preoperative abdominal computed tomographic scans were examined and measurements of perinephric fat (as a surrogate for intra-abdominal fat) and outer abdominal fat taken at uniform anatomical locations. Main Outcome Measures: We compared 30-day mortality and morbidity figures, length of stay, and operating times. Results: Body mass index had an influence on operative time (P = .02) but no significant effect on mortality, frequency of any complications, frequency of severe complications, or length of stay (P = .80, P = .89, P = .16, and P = .81, respectively). Outer abdominal fat had no significant effect on any of the 5 outcome measures. Perinephric fat measurements had a significant effect on most outcome measures (P = .004 for mortality, P = .003 for frequence of complications, P < .001 for frequence of severe complications, and P = .001 for length of stay). Conclusions: Outer appearances of obesity do not correlate with poor outcomes for major upper abdominal operations. A simple measurement of perinephric fat, as a surrogate for intra-abdominal fat, on preoperative imaging gives a more useful risk assessment for patients undergoing major upper abdominal operations.