Cis-atracurium is preferred over atracurium, because:
Ans. (B) It causes less release of histamine(Ref: Miller's 7th/e p869)Both atracurium and cis-atracurium are non-depolarizing neuromuscular blockers.Both of these are intermediate acting agents (both have same duration of action).Both of these agents are cardiostableAtracurium has faster onset of action as compared to cis-atracurium.Both are eliminated by Hoffman's elimination. Atracurium is also metabolized by liver to some extent and result in production of a metabolite laudanosine that can cause CNS toxicity including seizures. On the other hand cis-atracurium is almost completely eliminated by Hoffman's elimination and produce negligible laudanosine.Major advantage of cis-atracurium over atracurium is that the former do not release histamine.Note: Only cis-atracurium and doxacurium are the drugs in this category (whose name ends with curium) that do not release histamine.
It has rapid onset of action
It causes less release of histamine
It has short duration of action
It has less depressant action on heart
Anaesthesia