Plasma cholinesterase (pseudocholinesterase) activity is markedly reduced in a patient prior to surgery. This finding is most clinically significant because it predicts prolonged action of which drug?
- A Succinylcholine ✓
- B Vecuronium
- C Pancuronium
- D Rocuronium
Correct answer: A. Succinylcholine
Explanation
Succinylcholine (suxamethonium) is a depolarising neuromuscular blocker hydrolysed by plasma pseudocholinesterase. Patients with reduced pseudocholinesterase activity (due to liver disease, inherited dibucaine-resistant variants, organophosphate poisoning, or pregnancy) cannot hydrolyse succinylcholine quickly, resulting in prolonged neuromuscular blockade and apnoea. Vecuronium, pancuronium, and rocuronium are non-depolarising agents eliminated by hepatic metabolism or Hofmann degradation, not by pseudocholinesterase.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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