Nokea
Which of the following is a direct-acting parasympathomimetic that readily passes the blood-brain barrier and is commonly used in the treatment of glaucoma:
- A. Pilocarpine
- B. Carbachol
- C. Methacholine
- D. Bethanechol
Correct Answer: A
Rationale: The correct answer is A: Pilocarpine. Pilocarpine is a direct-acting parasympathomimetic that readily passes the blood-brain barrier due to its small molecular size. It is commonly used in the treatment of glaucoma by constricting the pupil and increasing the outflow of aqueous humor. Carbachol and Bethanechol are also parasympathomimetics, but they do not readily cross the blood-brain barrier. Methacholine is a muscarinic receptor agonist, not commonly used in the treatment of glaucoma. Therefore, the most suitable choice that meets the criteria provided in the question is pilocarpine.
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Miss White, a known diabetic, is experiencing headache, weakness, irritability, lack of muscular coordination, and apprehension. The nurse realizes that these are early symptoms of
- A. diabetic ketoacidosis
- B. hyperglycemic hyperosmolar nonketotic coma (HHNK)
- C. microangiopathy
- D. hypoglycemia
Correct Answer: D
Rationale: These are all early symptoms of hypoglycemia, which occurs when blood sugar drops too low.
What do the following hormones have in common: growth hormone, cortisol, and epinephrine? All:
- A. are secreted by the adrenal glands.
- B. raise blood glucose.
- C. suppress gluconeogenesis.
- D. are steroids.
Correct Answer: B
Rationale: Step-by-step rationale for why choice B is correct:
1. Growth hormone, cortisol, and epinephrine all raise blood glucose levels.
2. Growth hormone promotes glucose production, cortisol increases blood sugar through gluconeogenesis, and epinephrine stimulates glycogen breakdown.
3. The increase in blood glucose is essential for providing energy during stress or physical activity.
4. None of the other choices align with all three hormones' functions, making choice B the correct answer.
Summary: Choices A and D are incorrect because not all three hormones are secreted by the adrenal glands or are steroids. Choice C is incorrect as these hormones do not suppress gluconeogenesis; instead, they promote processes that raise blood glucose levels.
Non-selective β-blockers are contraindicated in:
- A. Angina of effort
- B. Systemic hypertension
- C. Peripheral vascular disease
- D. Thyrotoxicosis
Correct Answer: C
Rationale: The correct answer is C: Peripheral vascular disease. Non-selective β-blockers can cause vasoconstriction and exacerbate peripheral vascular disease by reducing blood flow to the extremities. This can lead to worsening symptoms and potential tissue damage. Choices A, B, and D are incorrect because non-selective β-blockers are commonly used in angina of effort, systemic hypertension, and thyrotoxicosis, respectively, to decrease heart rate and blood pressure.
Mrs. Good, a diabetic, states that she has taken the oral hypoglycemic, phenformin hydrochloride (DBI), for years. From this information, the nurse knows that Mrs. Good
- A. has not been receiving close medical supervision
- B. has moderately severe diabetes
- C. has active beta-cell function
- D. will soon need to switch to insulin therapy
Correct Answer: A
Rationale: Phenformin has been largely discontinued due to safety concerns, and it suggests the patient may not be receiving proper diabetes management.
A patient presents with rhabdomyolysis and depletion of 2-3-diphosphoglycerate. A common complication of high levels of the molecule being affected in this patient would be:
- A. Metastatic Calcification
- B. Dystrophic Calcification
- C. Heart Failure
- D. Respiratory Failure
Correct Answer: A
Rationale: The correct answer is A: Metastatic Calcification. Rhabdomyolysis leads to release of intracellular contents, including 2-3-diphosphoglycerate, causing hyperphosphatemia. High phosphates bind with calcium and deposit in tissues, leading to metastatic calcification. Dystrophic calcification occurs in damaged tissues, not due to high levels of 2-3-diphosphoglycerate. Heart failure and respiratory failure are not directly related to the depletion of this molecule.