Question

1. which volatile anesthetic is the most soluble (highest blood:gas)?

a. n₂o
b. desflurane
c. sevoflurane
d. isoflurane

1. which induction drug works mainly by enhancing gaba at the gaba receptor?

a. ketamine
b. propofol
c. dexmedetomidine
d. fentanyl

1. which drug is an nmda receptor antagonist?

a. midazolam
b. ketamine
c. rocuronium
d. morphine

1. succinylcholine is rapidly broken down by?

a. plasma cholinesterase
b. acetylcholinesterase
c. hepatic microsomal enzymes
d. monoamine oxidase

Explanation:

1. Blood-gas solubility of volatile anesthetics: Isoflurane has higher solubility than N₂O, Desflurane, and Sevoflurane.
2. Propofol's mechanism of action: It enhances GABAergic neurotransmission at GABAₐ receptors, unlike the other options with different primary mechanisms.
3. NMDA receptor antagonists: Ketamine is a well-known NMDA receptor antagonist, while the other drugs target different receptors/ pathways.
4. Succinylcholine metabolism: It is broken down by plasma cholinesterase (pseudocholinesterase); acetylcholinesterase does not metabolize it.

Answer:

1. D. Isoflurane
2. B. Propofol
3. B. Ketamine
4. A. Plasma cholinesterase (pseudocholinesterase)