title: The dose effect of ephedrine on the onset time of vecuronium.
abstract: A small dose of ephedrine decreases the onset time of rocuronium and cisatracurium; however, ephedrine might be associated with adverse hemodynamic effects. The appropriate dose of ephedrine has not been determined. We, therefore, studied 120 patients anesthetized with fentanyl 2 microg/kg and propofol 2-2.5 mg/kg who were randomly divided to receive either ephedrine (30, 70, or 110 microg/kg) or saline. During propofol anesthesia, the neuromuscular block was monitored by mechanomyography by using submaximal current of train-of-four stimulation every 10 s. To determine cardiac output, a transcutaneous Doppler probe was placed externally at the suprasternal notch. Tracheal intubation was performed by a blinded investigator at 2 min after vecuronium. Neuromuscular block, intubating conditions, and hemodynamic effects were measured during the induction of anesthesia. Both ephedrine 70 and 110 microg/kg improved intubating conditions at 2 min after vecuronium; however, 110 microg/kg was associated with adverse hemodynamic effects. We conclude that ephedrine 70 microg/kg given before the induction of anesthesia improved intubating conditions at 2 min after vecuronium, probably by increased cardiac output without significant adverse hemodynamic effects.
  
  
  CONCLUSIONS
  Ephedrine 70 microg/kg given before the induction of anesthesia improved tracheal intubating conditions at 2 min after vecuronium by increased cardiac output without significant adverse hemodynamic effects.
authors.affiliation: Department of Anesthesiology, Hanyang University Hospital, Seoul, Korea.
authors.forename: Kyo S
authors.initials: KS
authors.lastname: Kim
authors.forename: Mi A
authors.initials: MA
authors.lastname: Cheong
authors.forename: Jeong W
authors.initials: JW
authors.lastname: Jeon
authors.forename: Jeong H
authors.initials: JH
authors.lastname: Lee
authors.forename: Jae C
authors.initials: JC
authors.lastname: Shim
mesh_terms: D000328:Adult; D000771:Anesthesia, Intravenous; D018686:Anesthetics, Intravenous; D001794:Blood Pressure / Q000187:drug effects; D001993:Bronchodilator Agents / Q000494:pharmacology*; D002302:Cardiac Output / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D004809:Ephedrine / Q000494:pharmacology*; D005260:Female; D005283:Fentanyl; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D003473:Neuromuscular Nondepolarizing Agents; D015742:Propofol; D013997:Time Factors; D014655:Vascular Resistance / Q000187:drug effects; D014673:Vecuronium Bromide
chemical_list: D018686:Anesthetics, Intravenous; D001993:Bronchodilator Agents; D003473:Neuromuscular Nondepolarizing Agents; D014673:Vecuronium Bromide; D004809:Ephedrine; D005283:Fentanyl; D015742:Propofol