title: [Effect of age on ED50 of rocuronium for intratracheal intubation in female patients].
abstract: OBJECTIVE
  To determine the half-effective dose (IED50) of rocuronium for intratracheal intubation in female patients of different ages by sequential experiments and evaluate the effect of age on IED50 of rocuronium.
  
  
  METHODS
  Forty ASA class I-II female patients undergoing elective surgery under general anesthesia were randomly divided (n = 20) into young patient group and elderly patient group. The intratracheal intubation dose was divided into 4 grades by geometric progression, namely 0.24, 0.29, 0.35, and 0.42 mg/kg in the young patient group and 0.22, 0.26, 0.31, and 0.37 mg/kg in the elderly group. The IED(50) and 95% confidence interval (95%CI) of rocuronium during intubation in both groups were determined by sequential experiments.
  
  
  RESULTS
  The IED50 was 0.284 mg/kg in the elderly patient group, which was 91% that of in the young patient group (0.312 mg/kg), showing significant difference between the two groups (P < 0.05).
  
  
  CONCLUSIONS
  The IED50 of rocuronium is significantly lower in elderly female patients than in young female patients, suggesting the necessity of reducing the dose of rocuronium accordingly in anesthesia induction in elderly female patients.
authors.affiliation: Department of Anesthesiology, First Affiliated Hospital, Zhengzhou University, Zhengzhou 450052, China. zhangw571012@126.com
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Xiao-chong
authors.initials: XC
authors.lastname: Fan
authors.forename: Quan-cheng
authors.initials: QC
authors.lastname: Kan
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000732:Androstanols / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal; D008875:Middle Aged; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage*; D000077123:Rocuronium; D012737:Sex Factors
chemical_list: D000732:Androstanols; D003473:Neuromuscular Nondepolarizing Agents; D000077123:Rocuronium