ATI RN
Central and Peripheral Nervous System Drugs Questions
Question 1 of 5
Which of the following adverse effects would most likely occur after the administration of another dose of lidocaine near the brachial plexus for a peripheral nerve block?
Correct Answer: D
Rationale: The correct answer is D: Convulsions. Lidocaine is a local anesthetic that can cause central nervous system toxicity, leading to symptoms like seizures or convulsions. When administered near the brachial plexus for a peripheral nerve block, lidocaine can inadvertently reach systemic circulation, increasing the risk of CNS side effects. Ventricular tachycardia (A) is a cardiac adverse effect, not commonly associated with lidocaine toxicity. Abdominal colic (B) is unrelated to lidocaine administration near the brachial plexus. Drowsiness (C) is a common systemic side effect of lidocaine but is less likely to occur after administration near the brachial plexus compared to CNS effects like convulsions.
Question 2 of 5
Which of the following structures was most likely the site of therapeutic action of botulinum toxin injected into the ocular muscles of the 22-year-old man with strabismus?
Correct Answer: B
Rationale: The correct answer is B: Somatic nerve terminals. Botulinum toxin acts by inhibiting the release of acetylcholine at the neuromuscular junction, leading to muscle paralysis. In the context of ocular muscles in strabismus, the toxin would target the somatic nerve terminals that innervate the extraocular muscles. This action results in the relaxation of the affected muscle, helping to correct the misalignment of the eyes. Choices A, C, and D are incorrect as they do not directly relate to the mechanism of action of botulinum toxin at the neuromuscular junction.
Question 3 of 5
Which of the following muscle relaxants was most likely given to a patient who exhibited transient muscle fasciculations that progressed to generalized paralysis within 1 minute of administration?
Correct Answer: B
Rationale: The correct answer is B: Succinylcholine. Succinylcholine is a depolarizing neuromuscular blocker that causes initial muscle fasciculations followed by flaccid paralysis within minutes. This pattern of transient fasciculations progressing to generalized paralysis aligns with the patient's symptoms. Cisatracurium (A) and Vecuronium (D) are non-depolarizing neuromuscular blockers that do not typically cause fasciculations. Dantrolene (C) is a skeletal muscle relaxant used to treat malignant hyperthermia and muscle spasticity, but it does not cause the rapid progression of paralysis described in the scenario.
Question 4 of 5
Which of the following adverse effects was most likely to occur in the patient receiving local injections of botulinum toxin for benign essential blepharospasm?
Correct Answer: D
Rationale: The correct answer is D: Eyelid ptosis. Botulinum toxin injections can weaken the muscles, leading to eyelid ptosis (drooping). This is a common adverse effect seen in patients receiving these injections for benign essential blepharospasm. Other choices are incorrect: A, retinal detachment, is not associated with botulinum toxin injections; B, visual hallucinations, are not a common side effect; C, visual loss, is not a typical adverse effect of botulinum toxin injections for blepharospasm.
Question 5 of 5
This drug is effective in all forms of epilepsy in all age groups.
Correct Answer: B
Rationale: The correct answer is B: Carbamazepine. Carbamazepine is a broad-spectrum antiepileptic drug effective in various forms of epilepsy across all age groups. It works by stabilizing neuronal membranes and reducing repetitive firing of neurons. Acetazolamide (A) is a diuretic used for certain types of seizures. Ethosuximide (C) is mainly used for absence seizures. Felbamate (D) is reserved for refractory epilepsy cases due to its potential serious side effects. Therefore, Carbamazepine is the best choice for treating epilepsy across different forms and age groups.