Final answer:
A choledochojejunostomy is the surgical creation of a new opening between the common bile duct and the jejunum, which provides an alternative pathway for bile to reach the small intestine when the normal route is unavailable.
Step-by-step explanation:
The new opening between the common bile duct and the jejunum is known as a choledochojejunostomy. This procedure is typically performed to provide an alternative pathway for bile to reach the small intestine, especially when the normal route through the common bile duct is blocked or damaged. The common bile duct is a structure formed by the union of the common hepatic duct and the gallbladder's cystic duct, and it allows bile to flow into the small intestine, particularly the duodenum, which is the first part of the small intestine. However, in this surgical procedure, the connection is made directly to the jejunum, bypassing the duodenum. This is important as the bile aids in the digestion and absorption of fats by emulsifying lipids through bile salts.