Muscle Relaxants

Abstract

Originally published by Springer-Verlag Tokyo in 1995. Softcover reprint ofthe hardcover lst edition 1995 This work is subject to copyright. AII rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of iIIustrations, recitation, broadcasting, reproduction on microfilms or in other ways, and st<;>rage in data banks. The use of registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product Iiability: The publisher can give no guarantee for information about drug dosage and application thereof contained in this book. In every individual case the respective user must check its accuracy by consulting other pharmaceuticalliterature. PrefaceThe Fifth International Neuromuscular Meeting was held in Tokyo from November 17 through 20, 1994, and it was my privilege to chair these proceedings. It might seem to some that everything that can be said about the pharmacology of neuromuscular blocking agents (NBA) and their antagonists, the clinical use of NBAs, and the anatomy and physiology of neuromuscular receptor sites has already been said. From the beginning of the meeting, it became clear, not surprisingly, that such is not the case.It was a tortuous path from the first recorded clinical use of a curariform substance by Lawen in 1912 to the introduction of Intocostrin by Griffith in Canada, as reported in a 1942 issue of Anesthesiology. The practice of anesthesiology and surgery was changed forever. It was to be many years before a clear understanding of the neuromuscular junction (NMJ) and receptor pharmacology emerged. Prejunctional and post junctional actions of NBAs can now be differentiated and these data are clearly presented in these proceedings. The effects of catecholamine stress, burns, immobilization, and endotoxicosis as well as those from chronic infusions of curare and succinylcholine on NMJ pertubations have been elucidated. Recent studies utilizing the tools of molecular biology have helped to explain both prolonged blockade and sudden, lethal hyperkalemia following the administration of succinylcholine.Special considerations are addressed for administering NBAs to children, the elderly, and those with impaired renal and hepatic function. The relationship between the pharmacokinetics of d-Tubocurarine (dTc) , vecuronium, and atracurium and the volume of distribution in children is discussed, as is the decreased prejunctional acetylcholine stores in neonates and infants. In the elderly, elimination of NBAs (except for atracurium and, possibly, pipecuronium) is delayed due to decreased plasma clearance. In this respect, atracurium is unique since its half-life is independent of either renal or hepatic function. Elimination pathways of the new steroidal NBAs have not been established. The reader will be reminded, however, that the influence of hepatic disease ...