Effects of Neostigmine and Pyridostigmine on the Cardiovascular Responses in Inhalation Anesthesia

Kang, Hyo Seok; Lee, Guie Yong; Lee, Choon Hi

Abstract

At the end of the operation, residual neuromusular blookade may be antagonized by anticholines-terase (edrophonium, neostigmine and pyridostigmine). Neostigmine is probably commonly used antagonist of nondepolarizing neuromuscular blocking agents. But, because of an apparent longer duration of action and lesser muscarinic effects, pyridos- tigmine has been suggested as possibly superior to neostigmine as an antagonist of nondepolarizing neuromuscular blockade. Accordingly, present study observed the heart rate, systolic and diastolic blood pressure changes following equipotent doses of pyridostigmine and neostigmine given with glycopyrrolate in inhalation anesthesia (halothane and enflurane). Eighty patients were randomly divided in four groups as follows: Group I: halothane, glycopyrrolate + neostigmine Group II: halothane, glycopyrrolate + pyridostigmine Group IIl: enflurane, glycopyrrolate + neostigmine Group IV: enflurane, glycopyrrolate +pyridostigmine The results were as follows: 1) In halothane and enflurane anesthesia, the changes in heart rate were significant in each group after 4 minutes and especially, the group I, III showed more decrease than the group II, IV. 2) Tachycardia were observd until 6 minutes after administration of anticholinesterase in each group. Bradycardia were appeared at 6 minutes in the group I, IIl and at 14 minutes in the group II, IV and, each group showed bradycardia which continued over 20 mintes. 3) Even though the decrease of systolic and diastolic blood pressure showed transiently with time, there were no significant difference in the changes in ach group. 4) When the same anticholinesterase was administered, the cardiovascular responses were no significant difference between the halothane and enfurane anesthesia. In conclusion, pyridostigmine with glycopyrrolate seems to produce minimal changes in the cadiovascular responses in halothane and enflurane anesthesia.