Final answer:
Cholestyramine is typically administered post-surgically after a gastric bypass surgery like Roux-En-Y to prevent post-surgical diarrhea caused by bile acid malabsorption. The correct answer is option (a).
Step-by-step explanation:
The administration of cholestyramine (a bile binder) is typically considered after certain types of gastrointestinal surgeries where there is an increased risk of bile acid malabsorption causing post-surgical diarrhea. One such procedure is the gastric bypass, specifically the Roux-En-Y gastric bypass. This surgical procedure alters the digestive system to limit food intake and nutrient absorption, resulting in a small pouch being formed at the top of the stomach with the jejunum directly attached to the pouch. As a result of bypassing the majority of the stomach and the duodenum, the flow of bile is also altered, which may necessitate the use of cholestyramine to bind excess bile acids and prevent diarrhea.
Cholestyramine binds to bile acids in the intestine, preventing their reabsorption and subsequent irritation of the intestinal lining which can cause diarrhea. The Whipple procedure, appendectomy, and tonsillectomy are not typically associated with the same risk of bile acid malabsorption, and therefore, cholestyramine is not commonly used post-surgically for these procedures.
To give further context, bile is produced by the liver and stored in the gallbladder, aiding in the digestion of fats. It is secreted into the small intestine where it emulsifies fats to facilitate their absorption. After gastric bypass surgery, where the process of digestion is altered, cholestyramine can be helpful in managing the side effects of this altered bile flow.