ATI RN
Central Nervous System Stimulants and Related Drugs NCLEX Questions Quizlet Questions
Question 1 of 5
Which of the following drugs was most likely administered for muscle relaxation in the 74-year-old man with impaired hepatic and renal function undergoing abdominal surgery?
Correct Answer: C
Rationale: In a patient with impaired hepatic and renal function, Vecuronium is the most appropriate choice for muscle relaxation as it is primarily eliminated through hepatic metabolism and does not require renal excretion. Succinylcholine is contraindicated in patients with impaired renal function due to the risk of hyperkalemia. Tubocurarine, Mivacurium, and Cisatracurium may have prolonged effects in patients with impaired liver function, making Vecuronium the safest choice in this scenario.
Question 2 of 5
Which of the following muscle relaxants would be contraindicated in a patient with a deficiency of plasma cholinesterase?
Correct Answer: A
Rationale: Tubocurarine is a non-depolarizing muscle relaxant that is metabolized by plasma cholinesterase. In a patient with a deficiency of plasma cholinesterase, tubocurarine would not be metabolized properly, leading to prolonged effects and potential toxicity. Therefore, it would be contraindicated in this patient.
Question 3 of 5
Which of the following muscle relaxants was most likely given to a patient who exhibited transient muscle fasciculations followed by generalized paralysis within 1 minute of administration?
Correct Answer: B
Rationale: In this scenario, the correct answer is B) Succinylcholine. Succinylcholine is a depolarizing neuromuscular blocker that acts quickly by initially causing muscle fasciculations before inducing paralysis. This rapid onset of action is due to its ability to bind to the acetylcholine receptor, leading to sustained depolarization of the motor endplate. Option A) Cisatracurium is a non-depolarizing neuromuscular blocker that does not cause fasciculations or rapid onset paralysis like succinylcholine. Option C) Dantrolene is a skeletal muscle relaxant used to treat malignant hyperthermia and spasticity but does not cause the described rapid onset of paralysis. Option D) Vecuronium is a non-depolarizing neuromuscular blocker that also does not exhibit the rapid onset of action seen with succinylcholine. Educationally, understanding the mechanisms of action of different muscle relaxants is crucial for healthcare providers, especially in anesthesia and critical care settings. Recognizing the unique characteristics of each drug can help in selecting the most appropriate agent for specific clinical scenarios, optimizing patient care, and avoiding adverse events.
Question 4 of 5
A 34-year-old woman suffering from hemifacial spasms started treatment with botulinum toxin injected directly into the abnormally contracting muscles. Which of the following molecular actions most likely mediated the therapeutic effect of the drug in the patient's disorder?
Correct Answer: D
Rationale: The correct answer is D. Botulinum toxin works by inhibiting the release of acetylcholine from cholinergic terminals, leading to muscle paralysis and relaxation. This action prevents the excessive muscle contractions seen in hemifacial spasms. Inhibition of acetylcholine exocytosis from cholinergic terminals is the mechanism behind the therapeutic effect of botulinum toxin in this case.
Question 5 of 5
Which of the following drugs would be most appropriate for this patient?
Correct Answer: B
Rationale: Baclofen is a muscle relaxant commonly used to treat muscle spasms, making it the most appropriate choice for a patient with muscle spasms. Phenobarbital is an antiseizure medication and would not be indicated for this patient. Tubocurarine and succinylcholine are neuromuscular blocking agents used during surgery, but baclofen would be more appropriate for muscle spasms outside of surgical settings. Chlorpromazine is an antipsychotic medication and would not be indicated for muscle spasms.