Effects of cholinesterase inhibitors on the neuromuscular blocking action of suxamethonium.
Prolonged neuromuscular block occurs when suxamethonium is given after neostigmine or pyridostigmine; however, studies of edrophonium and suxamethonium have yielded conflicting results. We have studied, therefore, interactions between suxamethonium and all three anticholinesterases in rats anaesthetized with pentobarbitone. After recovery from an initial bolus of suxamethonium, saline, edrophonium, pyridostigmine or neostigmine was administered and a second dose of suxamethonium was then given. All three anticholinesterases prolonged the duration of neuromuscular block (90% suppression to 50% twitch recovery) to 127 (SEM 9)%, 127(10)% and 138 (11)% of baseline for edrophonium, pyridostigmine and neostigmine, respectively. Recovery index (25% to 75% twitch recovery) was increased also to 125 (9)%; 149 (10%) and 185 (15)% of baseline, respectively for the three drugs.
Valdrighi
J B
JB
Department of Anesthesiology, University of California Davis 95616.
Fleming
N W
NW
Smith
B K
BK
Baker
G L
GL
White
D A
DA
D000818:Animals; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D004347:Drug Interactions; D004491:Edrophonium / Q000494:pharmacology; D006614:Hindlimb; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009388:Neostigmine / Q000494:pharmacology; D011729:Pyridostigmine Bromide / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013390:Succinylcholine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D013997:Time Factors
D002800:Cholinesterase Inhibitors; D009388:Neostigmine; D004491:Edrophonium; D013390:Succinylcholine; D011729:Pyridostigmine Bromide