Challenging case with a closed loop obstruction and internal hernia in the context of a gastric bypass. Interpretation of such cases is increasingly difficult due to the different limbs - the afferent or hepatobiliary, which is obstructed in this case compared to the alimentary limb which is not dilated. It is important to communicate this distinction to the surgery team, who may reflexively reach for the nasogastric tube, which will not help at all in this case and consideration of conservative management will delay the need to decompress the obstructed afferent limb. 

Surgery confirmed internal hernia of the pancreaticobiliary limb of the bypass through a mesenteric defect created by the jejunojejnostomy, and resulting in the need for resection of 40 cm of small bowel and the JJ with revision.