ATI RN
Cardiovascular Drugs Pharmacology Slideshare Questions
Question 1 of 5
Indicate the neuromuscular blocker, whose breakdown product readily crosses the blood-brain barrier and may cause seizures:
Correct Answer: D
Rationale: The correct answer is D: Atracurium. Atracurium is metabolized to laudanosine, which readily crosses the blood-brain barrier and may cause seizures. Pancuronium (A) does not readily cross the blood-brain barrier. Succinylcholine (B) does not have a breakdown product that crosses the blood-brain barrier. Tubocurarine (C) does not produce a breakdown product that causes seizures.
Question 2 of 5
Which of the following alfa receptor antagonists is useful in reversing the intense local vasoconstriction caused by inadvertent infiltration of norepinephrine into subcutaneous tissue during intravenous administration?
Correct Answer: B
Rationale: The correct answer is B: Phentolamine. Phentolamine is an alpha receptor antagonist that can rapidly reverse the vasoconstriction caused by local infiltration of norepinephrine. It works by blocking alpha receptors, leading to vasodilation and improved blood flow in the affected area. Propranolol (A) is a beta-blocker and not effective in reversing alpha receptor-mediated vasoconstriction. Tamsulosin (C) is an alpha-1 blocker primarily used for benign prostatic hyperplasia, not for acute vasoconstriction reversal. Ergotamine (D) is a vasoconstrictor used in treating migraines, which would exacerbate the problem in this scenario.
Question 3 of 5
Barbiturates are being replaced by hypnotic benzodiazepines because of:
Correct Answer: D
Rationale: The correct answer is D: All of the above. Barbiturates have a low therapeutic index, leading to a narrow range between therapeutic and toxic doses. They suppress REM sleep, which can lead to negative effects on sleep quality. Barbiturates also have a high potential for physical dependence and abuse, making them less desirable compared to benzodiazepines. Therefore, all the given reasons collectively contribute to the shift towards using hypnotic benzodiazepines over barbiturates.
Question 4 of 5
The mechanism of valproate action is:
Correct Answer: D
Rationale: The correct answer is D: All of the above. Valproate's mechanism of action involves multiple pathways. 1. Valproate facilitates GABA synthesis by inhibiting GABA breakdown enzyme and enhancing GABA accumulation. 2. It inhibits voltage-sensitive Na+ channels, reducing neuronal excitability. 3. It also inhibits low threshold (T-type) Ca2+ channels, further reducing neuronal excitability. These combined actions lead to increased GABAergic transmission and decreased excitatory neurotransmission, contributing to its antiepileptic and mood stabilizing effects. Other choices are incorrect because they do not encompass all the mechanisms involved in valproate's action.
Question 5 of 5
Indicate the chemical mediator in the antinociceptive descending pathways:
Correct Answer: D
Rationale: The correct answer is D: All of the above. In the antinociceptive descending pathways, multiple endogenous opioids play a role in pain modulation. Beta-endorphin, met- and leu-enkephalin, and dynorphin all act as chemical mediators to inhibit pain signals. Each of these opioids bind to different opioid receptors in the central nervous system, contributing to the overall analgesic effect. Therefore, the correct answer includes all three options as they collectively participate in the antinociceptive pathways. Choices A, B, and C alone are not sufficient to fully explain the complexity of the pain modulation system, making option D the most comprehensive and accurate choice.