Mole for mole, which of the following has the greatest effect on plasma osmolality?
- A. Progesterone
- B. Cortisol
- C. Vasopressin
- D. Aldosterone
Correct Answer: C
Rationale: Plasma osmolality is primarily regulated by the concentration of solutes in the blood. Vasopressin, also known as antidiuretic hormone (ADH), plays a key role in regulating water reabsorption in the kidneys, thus affecting plasma osmolality. When plasma osmolality increases, vasopressin is released to increase water reabsorption, leading to a decrease in plasma osmolality. Progesterone, cortisol, and aldosterone do not directly influence water reabsorption and therefore do not have as significant an impact on plasma osmolality as vasopressin.
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What preoperative instruction should the nurse give to the patient scheduled for a subtotal thyroidectomy?
- A. How to support the head with the hands when turning in bed
- B. Coughing should be avoided to prevent pressure on the incision
- C. Head and neck will need to remain immobile until the incision heals
- D. Any tingling around the lips or in the fingers after surgery is expected and temporary
Correct Answer: A
Rationale: It is important to teach the patient how to support the head when turning to avoid tension on the incision and reduce the risk of bleeding or stress on the surgical site.
Priority Decision: When caring for a patient with metabolic syndrome, what should the nurse give the highest priority to teaching the patient about?
- A. Achieving a normal weight
- B. Eliminating red meat from the diet
- C. Performing daily aerobic exercise
- D. Monitoring the blood glucose periodically
Correct Answer: A
Rationale: Achieving and maintaining a normal weight is the highest priority in managing metabolic syndrome and preventing further complications.
Which of the following is the response to low plasma levels of calcium?
- A. Secretion of calcitonin
- B. Secretion of the beta cells of the islets of Langerhans
- C. Inhibition of the adenohypophyseal release of ACTH
- D. Secretion of PTH
Correct Answer: D
Rationale: The correct answer is D: Secretion of PTH. Low plasma levels of calcium trigger the parathyroid glands to release parathyroid hormone (PTH) to increase calcium levels. PTH acts on the bones to stimulate calcium release, on the kidneys to increase calcium reabsorption, and on the intestines to enhance absorption.
A: Secretion of calcitonin is incorrect because calcitonin is released in response to high calcium levels to lower them.
B: Secretion of the beta cells of the islets of Langerhans is incorrect as these cells secrete insulin in response to high blood glucose levels.
C: Inhibition of the adenohypophyseal release of ACTH is incorrect as ACTH is related to stress response, not calcium regulation.
An enlargement of the thyroid gland is the condition known as .
- A. acromegaly
- B. goiter
- C. parathyroidism
- D. Cushing's disease
Correct Answer: B
Rationale: The correct answer is B: goiter. An enlargement of the thyroid gland is specifically referred to as a goiter. This condition can be caused by iodine deficiency or other factors affecting thyroid hormone production. Acromegaly (A) is a disorder caused by excessive growth hormone, unrelated to the thyroid. Parathyroidism (C) refers to issues with the parathyroid glands, not the thyroid. Cushing's disease (D) is a condition involving excessive cortisol production, not thyroid enlargement. Therefore, the correct term for an enlarged thyroid gland is goiter.
The following statements concerning prazosin and phentolamine are correct EXCEPT:
- A. Both antagonize alpha1-receptors
- B. Both cause the same degree of tachycardia
- C. Both decrease blood pressure
- D. Both are competitive antagonists
Correct Answer: B
Rationale: Correct Answer: B
Rationale:
1. Prazosin and phentolamine both antagonize alpha1-receptors, leading to vasodilation and decreased blood pressure.
2. Both drugs are competitive antagonists, competing with norepinephrine at alpha1-receptors.
3. However, phentolamine causes reflex tachycardia due to its non-selective alpha-adrenergic blockade, unlike prazosin.
4. Therefore, the statement that both cause the same degree of tachycardia is incorrect based on their pharmacological differences.