Which of the following was most likely the primary reason for the use of cisatracurium instead of tubocurarine in this patient?

Correct Answer: C

Rationale: The correct answer is C: Propofol induction. Cisatracurium is preferred over tubocurarine for patients undergoing propofol induction due to its faster onset and shorter duration of action, aligning with propofol's rapid onset and short duration. This minimizes the risk of prolonged muscle paralysis and respiratory depression. Liver insufficiency (A) and renal insufficiency (D) would not affect the choice between cisatracurium and tubocurarine. Advanced age (B) alone is not a primary factor for choosing cisatracurium over tubocurarine.

Correct Answer: A

Rationale: Valproic acid is the correct answer because it exhibits dose-dependent elimination kinetics, meaning its clearance rate changes with dosage. In patients with epilepsy, maintaining steady drug levels is crucial for seizure control. Valproic acid's dose-dependent elimination allows for more predictable drug levels at higher doses. Lamotrigine, phenytoin, and topiramate do not exhibit this characteristic. Lamotrigine has time-dependent kinetics, phenytoin follows Michaelis-Menten kinetics, and topiramate has linear kinetics. Therefore, Valproic acid is the most likely drug taken by the patient.

Correct Answer: B

Rationale: The correct answer is B: Topiramate. For a boy, topiramate is most appropriate due to its efficacy in treating various types of seizures, including absence seizures common in children. It has a favorable side effect profile and can be used as monotherapy. Carbamazepine (A) is not ideal for absence seizures, Diazepam (C) is more for acute seizure management, and Ethosuximide (D) is specifically for absence seizures and may not cover other seizure types.

Correct Answer: B

Rationale: The correct answer is B: Ethosuximide. In a 15-month-old with episodes of powerful muscle contractions, the most likely diagnosis is childhood absence epilepsy, which is characterized by brief, subtle seizures involving staring and muscle contractions. Ethosuximide is the first-line treatment for childhood absence epilepsy due to its efficacy and favorable side effect profile in young children. Carbamazepine (A) is not typically used for absence seizures. Phenytoin (C) and Phenobarbital (D) are not recommended for childhood absence epilepsy and may have more side effects in this age group.

Correct Answer: D

Rationale: Rationale: 1. Perampanel is a non-competitive antagonist of AMPA receptors, effective for partial seizures. 2. Lamotrigine is commonly used for partial seizures, making Perampanel a suitable add-on therapy. 3. Levetiracetam, Felbamate, and Topiramate are less commonly used or not as effective for partial seizures. Summary: Levetiracetam, Felbamate, and Topiramate are not the best choices due to their lower efficacy or different mechanisms of action compared to Perampanel, which is specifically effective for partial seizures and suitable as an add-on therapy in this case.