Which of the following is not true about principal hormonal responses to surgical stress?
**Core Concept**
The principal hormonal responses to surgical stress involve the hypothalamic-pituitary-adrenal (HPA) axis, which leads to the release of glucocorticoids (cortisol) and catecholamines (adrenaline and noradrenaline). This response is mediated by the activation of the hypothalamic corticotropin-releasing hormone (CRH) and the release of adrenocorticotropic hormone (ACTH) from the pituitary gland.
**Why the Correct Answer is Right**
The release of glucocorticoids, such as cortisol, helps to mobilize energy stores, suppress the immune system, and maintain blood pressure. Catecholamines, such as adrenaline and noradrenaline, increase heart rate, blood pressure, and energy mobilization. The activation of the HPA axis is a critical response to surgical stress, allowing the body to adapt to the stress of surgery.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is not true. The HPA axis is activated in response to surgical stress, leading to the release of glucocorticoids and catecholamines.
**Option B:** This option is incorrect because it is not true. The release of insulin is not a direct response to surgical stress. However, insulin resistance can occur as a result of the stress response, leading to an increase in glucose levels.
**Option C:** This option is incorrect because it is not true. The release of aldosterone is a response to surgical stress, helping to regulate electrolyte balance and blood pressure.
**Option D:** This option is incorrect because it is not true. The release of antidiuretic hormone (ADH) is a response to surgical stress, helping to regulate fluid balance and blood pressure.
**Clinical Pearl / High-Yield Fact**
It is essential to recognize that the HPA axis is activated in response to surgical stress, leading to the release of glucocorticoids and catecholamines. This understanding is critical in managing patients undergoing surgery, particularly those with pre-existing endocrine disorders.
**Correct Answer:** B.