title: Smoking does not alter the dose-requirements and the pharmacodynamics of rocuronium.
abstract: OBJECTIVE
  Controversial data about the effect of smoking on the dose-requirements and the pharamcodynamics of rocuronium have been reported recently. This study was conducted to evaluate the dose-requirements and the pharmacodynamics of rocuronium in smokers using target controlled infusion.
  
  
  METHODS
  The dose-requirements of rocuronium for 60 min relaxation, using target controlled infusion, given under intravenous anaesthesia with propofol, fentanyl and nitrous oxide was studied in 37 smokers and 37 non-smokers. Initially 450 microg x kg(-1) rocuronium were administered, neuromuscular effects were quantified by recording the single twitch response of the adductor pollicis muscle after ulnar nerve stimulation using a force transducer, and the neuromuscular block was kept at 80% by target controlled infusion throughout the procedure.
  
  
  RESULTS
  The dose-requirements for one hour relaxation were 867 +/- 116 microg x kg(-1) x hr(-1) for smokers (S) and 839 +/- 149 microg x kg(-1) x hr(-1) for non-smokers (NS). The duration to 10% and the spontaneous recovery from 25% to 75% of the control twitch response also showed no differences between S (17.2 +/- 3.4 min, 10.6 +/- 0.9 min) and NS (18.9 +/- 4.3 min, 10.9 +/- 3.2 min), as well as maximum block, onset time and infusion rate.
  
  
  CONCLUSIONS
  Smoking does not alter the dose-requirements for rocuronium and no effects on the onset time, degree of block, time to maximum block, duration 10% and spontaneous recovery index were observed.
authors.affiliation: Department of Anaesthesia and General Intensive Care Medicine, University of Innsbruck, Austria. friedrich.puehringer@uibk.ac.at
authors.forename: F K
authors.initials: FK
authors.lastname: Pühringer
authors.forename: P
authors.initials: P
authors.lastname: Keller
authors.forename: A
authors.initials: A
authors.lastname: Löckinger
authors.forename: A
authors.initials: A
authors.lastname: Kleinsasser
authors.forename: A
authors.initials: A
authors.lastname: Scheller
authors.forename: C
authors.initials: C
authors.lastname: Raedler
authors.forename: C
authors.initials: C
authors.lastname: Keller
mesh_terms: D000328:Adult; D000732:Androstanols / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology; D003473:Neuromuscular Nondepolarizing Agents / Q000009:adverse effects*; D000077123:Rocuronium; D012907:Smoking / Q000503:physiopathology*
chemical_list: D000732:Androstanols; D003473:Neuromuscular Nondepolarizing Agents; D000077123:Rocuronium