Dumping syndrome occur due to:

Dumping syndrome refers to a constellation of postprandial symptoms occurring due to accelerated emptying (dumping) of hyperosmolar stomach contents into the small bowel. It is usually seen in operations which destroy the pyloric sphincter ( i.e gastrectomy, antrectomy and drainage procedures). It also affects a small percentage of patients with highly selective vagotomy due to loss of receptive relaxation of stomach. Remember: Dumping syndrome is also known as post-cibal syndrome. Ref: Bailey & Love 24/e, Page 1043 ; Schwaz 9/e, page 942.