Which statement describes opioid effects on endocrine physiology?

Which statement describes opioid effects on endocrine physiology?

• A. Large doses of fentanyl and sufentanil inhibit catecholamines, ADH, and cortisol more than inhaled anesthetics
• B. They increase BMR and temperature
• C. They stimulate vasopressin release
• D. They have no endocrine effects

Answer: (A)

Opioids markedly blunt the body's endocrine stress response to surgery. When large doses of fentanyl or sufentanil are used, they dampen the hypothalamic-pituitary-adrenal axis and the sympathetic output more than inhaled anesthetics. This translates to lower release of catecholamines (like epinephrine and norepinephrine), reduced ACTH and cortisol, and decreased vasopressin (ADH) release in response to surgical stress. That suppression of the hormonal response helps explain why these opioids have such a pronounced endocrine effect during anesthesia. Other statements don’t fit this pattern. Opioids do not typically cause a metabolic upturn with increased BMR or temperature; they also do have endocrine effects (contradicting “no endocrine effects”). And they are not known for stimulating vasopressin release in this context (they tend to blunt it as part of the stress-suppressing effect).

Opioids markedly blunt the body's endocrine stress response to surgery. When large doses of fentanyl or sufentanil are used, they dampen the hypothalamic-pituitary-adrenal axis and the sympathetic output more than inhaled anesthetics. This translates to lower release of catecholamines (like epinephrine and norepinephrine), reduced ACTH and cortisol, and decreased vasopressin (ADH) release in response to surgical stress. That suppression of the hormonal response helps explain why these opioids have such a pronounced endocrine effect during anesthesia.

Other statements don’t fit this pattern. Opioids do not typically cause a metabolic upturn with increased BMR or temperature; they also do have endocrine effects (contradicting “no endocrine effects”). And they are not known for stimulating vasopressin release in this context (they tend to blunt it as part of the stress-suppressing effect).