Gallbladder

About the Gallbladder

The gallbladder is a pear shaped sac approximately 7 to 10 cm long located under the liver, storing and concentrating bile between meals. It holds 30 to 50 mL of bile, concentrating hepatic bile 5 to 10 fold by absorbing water and electrolytes. The cystic duct connects to the common hepatic duct forming the common bile duct. Bile flow is regulated by the sphincter of Oddi hepatopancreatic sphincter, which relaxes in response to CCK released when fat enters the duodenum. Bile salts emulsify dietary fats into micelles for absorption. Gallstones cholelithiasis affect approximately 10 to 15 percent of adults, composed of cholesterol 80 percent or pigment bilirubin 20 percent. Classic risk factors include female sex, age over forty, pregnancy, obesity, and rapid weight loss. Biliary colic occurs when stones temporarily obstruct the cystic duct. Acute cholecystitis involves stone impaction causing inflammation, and is commonly treated by surgical removal of the gallbladder, cholecystectomy.