title: Dose-response relationship and infusion requirement of cisatracurium besylate in infants and children during nitrous oxide-narcotic anesthesia.
abstract: BACKGROUND
  To determine the effect of age on the dose-response relation and infusion requirement of cisatracurium besylate in pediatric patients, 32 infants (mean age, 0.7 yr; range, 0.3-1.0 yr) and 32 children (mean age, 4.9 yr; range, 3.1-9.6 yr) were studied during thiopentone-nitrous oxideoxygen-narcotic anesthesia.
  
  
  METHODS
  Potency was determined using a single-dose (20, 26, 33, or 40 microg/kg) technique. Neuromuscular block was assessed by monitoring the electromyographic response of the adductor pollicis to supramaximal train-of-four stimulation of the ulnar nerve at 2 Hz.
  
  
  RESULTS
  Least-squares linear regression analysis of the log-probit transformation of dose and maximal response yielded median effective dose (ED50) and 95% effective dose (ED95) values for infants (29+/-3 microg/kg and 43+/-9 microg/kg, respectively) that were similar to those for children (29+/-2 microg/kg and 47+/-7 microg/kg, respectively). The mean infusion rate necessary to maintain 90-99% neuromuscular block during the first hour in infants (1.9+/-0.4 microg x kg(-1) x min(-1); range: 1.3-2.5 microg x kg(-1) x min(-1)) was similar to that in children (2.0+/-0.5 microg x kg(-1) x min(-1); range: 1.3-2.9 microg x kg(-1) x min(-1)).
  
  
  CONCLUSIONS
  The authors conclude that cisatracurium is equipotent in infants and children when dose is referenced to body weight during balanced anesthesia.
authors.affiliation: Department of Anesthesia, The Hospital of Sick Children, University of Toronto, Ontario, Canada.
authors.forename: J
authors.initials: J
authors.lastname: de Ruiter
authors.forename: M W
authors.initials: MW
authors.lastname: Crawford
mesh_terms: D000367:Age Factors; D001279:Atracurium / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D005260:Female; D005283:Fentanyl / Q000494:pharmacology*; D006801:Humans; D007223:Infant; D008297:Male; D009294:Narcotics / Q000494:pharmacology*; D009466:Neuromuscular Blocking Agents / Q000494:pharmacology*; D009609:Nitrous Oxide / Q000494:pharmacology*
chemical_list: D009294:Narcotics; D009466:Neuromuscular Blocking Agents; D001279:Atracurium; D009609:Nitrous Oxide; C101584:cisatracurium; D005283:Fentanyl