Gallbladder

Function

The gallbladder is a 50 ml pear-shaped reservoir tucked under liver segment IV. Between meals it concentrates hepatic bile up to tenfold by pumping out water and sodium; a fatty meal triggers cholecystokinin, which squeezes its contents down the cystic duct into the duodenum within minutes.

Its Hartmann's pouch at the neck is the resting place of gallstones, and Calot's triangle (cystic duct, common hepatic duct, liver) is the critical view of safety in cholecystectomy — dividing the cystic artery and duct only once the triangle is cleared.

Blood supply

Cystic artery from the right hepatic artery within Calot's triangle.

Nerve supply

Coeliac plexus sympathetic; vagal parasympathetic; visceral afferents (T6–T9) refer pain to the epigastrium and right subscapular region; diaphragmatic irritation (phrenic nerve) refers to the right shoulder tip.

Clinical relevance

Gallstones (cholelithiasis)

Cholesterol-saturated bile precipitates stones — the 5 Fs mnemonic's fertile, forty, fat, female, fair; colic follows fatty meals.

Cholecystitis

An impacted stone inflames the wall — Murphy's sign arrests inspiration under the right costal margin; gangrene threatens the diabetic.

Related conditions

• Gallstones