RESUMO
BACKGROUND: Many surgeons prefer a narrow gastrojejunostomy in gastric bypass believing that this provides greater weight loss. The question is whether the anastomosis remains at its initial diameter, whether it narrows or widens over time. This study tests the hypothesis that the initial diameter of the anastomosis varies over time. MATERIALS AND METHODS: One hundred obese had undergone surgery. Group A with anastomosis 1.5 cm wide and group B with anastomosis 3 cm wide. One-year follow-up was done for 83 patients. The size of the anastomosis diameter was evaluated using a balloon for cardia dilation. RESULTS: Comparing the results of surgery with the values presented 1 year after the procedure, (i) BMI decreased from 43.3 ± 6.6 to 28.7 ± 7.0 kg/m2 for group A and 44.6 ± 5.9 to 29.1 ± 6.3 kg/m2 for group B, (ii) the total weight loss was 30.6 ± 4.7% for group A and 31.9 ± 5.2% for group B, and (iii) the initial 1.5-cm anastomosis in group A measured 2.3 ± 1.0 cm while the initial 3-cm anastomosis in group B measured 2.7 ± 1.0 cm 1 year after surgery. No statistically significant difference was found for any of the variables evaluated before and after the surgical procedure. CONCLUSION: Calibrated anastomosis has no utility in increasing weight loss in gastric bypass.