 The stomach is then disconnected from the duodenum and connected to the distal part of the small intestine.The duodenum and the upper part of the small intestine are reattached to the rest at about 75–100 cm from the colon.. Like the Roux en Y Bypass, it is now understood that its results are largely due to a significant alteration in gut hormones that control hunger and satiety, in addition to its restriction and malabsorption properties.The addition of the sleeve gastrectomy, causes further gut hormone set- point alterations by reducing levels of the hunger hormone, Ghrelin.