Which of the following physiological factors related to hepatobiliary function is MOST likely to increase during pregnancy?

  • □ (A) Hepatic blood flow
  • □ (B) Gallbladder contractility
  • □ (C) Serum alkaline phosphatase level
Physiological changes during pregnancy significantly impact the well-being of both mother and baby and are important to recognize for optimal anesthetic management. There are several relevant changes in hepatobiliary function that occur during pregnancy. Although cardiac output and blood flow to several organs (e.g., uterus, kidneys) increase significantly during pregnancy, hepatic blood flow does not change significantly. Most of the liver enzymes, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), remain within normal range. However, serum alkaline phosphatase more than doubles due to placental secretion of this enzyme.

Pregnancy is associated with an increased frequency of gallstone disease. Acute appendicitis and acute cholecystitis are the most common diseases requiring surgery during pregnancy. Several factors, including biliary stasis and changes in bile composition, are implicated in creating a lithogenic environment for this higher frequency of gallstone disease. An increase in progesterone during pregnancy causes relaxation of smooth muscle of the gallbladder. Hypomotility causes stasis in the gallbladder, which favors sludge and stone formation. Other contributory factors are increased secretion of bile and changes in bile composition, including increased cholesterol level and decreased amount of chenodeoxycholic acid in bile.

Answer: C