Which of the following diseases can augment the neuromuscular blockade produced by nondepolarizing muscle relaxants?

Correct Answer: A

Rationale: The correct answer is A: Myasthenia gravis. In myasthenia gravis, there is a decrease in the number of available acetylcholine receptors at the neuromuscular junction, leading to muscle weakness. Nondepolarizing muscle relaxants work by blocking acetylcholine receptors, so in myasthenia gravis, there are fewer receptors available for the drug to bind to, resulting in an augmented neuromuscular blockade. Burns (B), asthma (C), and Parkinsonism (D) do not directly affect the number of acetylcholine receptors at the neuromuscular junction, so they would not enhance the blockade produced by nondepolarizing muscle relaxants.

Correct Answer: A

Rationale: The correct answer is A: Labetalol. Labetalol is a non-selective beta blocker with additional alpha-1 blocking properties. This combination of alpha-1 and beta-blocking effects makes it unique among the choices. Alpha-1 blockade helps reduce peripheral vascular resistance, while beta-blocking action decreases heart rate and contractility. This dual mechanism makes labetalol effective in treating hypertension. Betaxolol (B) is a selective beta-1 blocker, Propranolol (C) is a non-selective beta blocker, and Timolol (D) is a non-selective beta blocker as well. These choices lack the alpha-1 blocking effect present in labetalol, making them incorrect for this question.

Correct Answer: A

Rationale: The correct answer is A, depression of the medullar respiratory center. Hypnotics can suppress the central nervous system, leading to respiratory depression, which can result in death. This is the most common cause of death in hypnotic overdoses. B: Hypothermia is not a usual cause of death in hypnotic overdoses. C: Cerebral edema is not a direct result of hypnotic overdose and would not typically be the cause of death. D: Status epilepticus is not a typical outcome of hypnotic overdose and would not directly lead to death in this context.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.