Surgery>>>>>Shock
Question 7#

Which of the following is true about antidiuretic hormone (ADH) production in injured patients?

A. ADH acts as a potent mesenteric vasoconstrictor
B. ADH levels fall to normal within 2 to 3 days of the initial insult
C. ADH decreases hepatic gluconeogenesis
D. ADH secretion is mediated by the renin-angiotensin system

Correct Answer is A

Comment:

The pituitary also releases vasopressin or antidiuretic hormone (ADH) in response to hypovolemia, changes in circulating blood volume sensed by baroreceptors and left atrial stretch receptors, and increased plasma osmolality detected by hypothalamic osmoreceptors. Epinephrine, angiotensin II, pain, and hyperglycemia increase production of ADH. ADH levels remain elevated for about 1 week after the initial insult, depending on the severity and persistence of the hemodynamic abnormalities. ADH acts on the distal tubule and collecting duct of the nephron to increase water permeability, decrease water and sodium losses, and preserve intravascular volume. Also known as arginine vasopressin, ADH acts as a potent mesenteric vasoconstrictor, shunting circulating blood away from the splanchnic organs during hypovolemia. This may contribute to intestinal ischemia and predispose to intestinal mucosal barrier dysfunction in shock states. Vasopressin also increases hepatic gluconeogenesis and increases hepatic glycolysis.