All release histamine except ?

Ans. is 'a' i.e., Pancuronium Propeies of NM Blockers Longest acting Neuromuscular blocker - Pancuronium (duration of action 120-180 minutes). (Goodman & Gilman 11 th/e p. 222) (Note: In some books pipecuronium or Doxacurium have given as the longer activity). Shoest and fastest acting neuromuscular blocker - Succinylcholine (suxamethonium) - duration of action 5-8 minutes. Shoest acting competitive (nondepolarizing) neuromuscular blocker - Mivacurium (duration of action 12-18 minutes). Fastest acting nondepolarizing blocker Rocuronium (can be used for endotracheal intubation as an alternative to Sch). Non-depolarizing neuro-muscular blockers can cause ganglion block, vagal block and Histamine release (different agents has different propensity). Histamine release is caused by - D-TC (maximum tendency), succinylcholine, mivacurium, doxacurium, atracurium, tubocurarine - can cause bronchoconstriction. Viually no histamine release - Pancuronium Vagal block is caused by Pancuronium, recuronium, Gallamine. Maximal vagal block and tachycardia is caused by - Pancuronium (Previously it was gallamine, but it is not used now). Vagal stimulation is caused by - succinylcholine (can cause bradycardia). Ganglion block is caused by - d-Tc, Metocurine, Alcuronium. Maximum ganglion blockade is caused by - d-TC. Ganglion stimulation is caused by - Succinylcholine.