Bowel length: measurement, predictors, and impact on bariatric and metabolic surgery.

Background: Small bowel length (SBL) determines the caloric absorptive capacity. The aim of this study was to evaluate SBL to identify patient-specific predictors and the interrelationships of SBL with anthropometric variables.

Methods: Sex, age, and weight were recorded at the time of surgery when SBL and the estimated jejunal length (JLe) were measured by 3 different methods.

Results: The mean SBL of 443 patients undergoing laparotomy (78% female) was 690±93.7 cm (range 350-1049 cm). Sex was correlated with SBL, as men had a longer small bowel than women (729±85 versus 678±92, P<.0001) and were significantly taller (173±8.2 versus 161±6.9, P<.001). Age did not correlate with SBL. The differences in length between fully stretched small bowel and nonstretched small bowel and between fully stretched small bowel and laparoscopic bowel were 137±19 cm and 32.4±11.4 cm, respectively. In a multivariate linear regression analysis model that included sex, age, height, and weight, only height was significantly correlated with SBL (P<.00001) and explained 12% of the variance in SBL. Sex, age, height, and JLe, but not SBL, were statistically highly significant in predicting 75% of the variance of body weight.

Conclusions: A positive association between height and SBL was found. Sex, age, height, and JLe may be strong predictors of weight. Individual JLe may be of importance in determining the weight loss and resolution of metabolic co-morbidities. Measuring the SBL can prevent the risk of nutritional consequences in malabsorptive, revisional, and metabolic procedures.