PGIMER Frequently Asked MCQ Topics | skeletal muscle relaxants undergo Hoffman’s elimination

Which of the following skeletal muscle relaxants undergo Hoffman’s elimination? 

a. Atracurium 
b. Cis-atracurium 
c. Mivacurium 
d. Vecuronium 
e. rocuronium

Ans. (A) Atracurium; (B) Cis-atracurium;

• Atracurium is a non-depolarizing muscle relaxant. Its unique feature is that it undergoes spontaneous non-enzymatic degradation (Hoffman elimination) in addition to degradation by plasma cholinesterase. Consequently its duration of action is not altered in patients with hepatic/renal insufficiency or hypodynamic circulation.

Cisatracurium: It is a R-cis, enantiomer of atracurium. It also undergoes spontaneous Hofman elimination, but  unlike atracurium it is not metabolized by plasma cholinesterase. It is 4 times more potent than atracurium, slow onset and similar duration of action.

•Mivacariam— Metabolized by plasma cholinesterase.