title: The optimal dose of remifentanil for acceptable intubating conditions during propofol induction without neuromuscular blockade.
abstract: OBJECTIVE
  To determine the optimal remifentanil dose required to provide acceptable intubating conditions following induction of anesthesia with propofol without using neuromuscular blockade.
  
  
  METHODS
  Dose-response study.
  
  
  METHODS
  Operating room of a university hospital.
  
  
  METHODS
  50 ASA physical status 1 men, aged between 20 and 40 years, who were scheduled for general anesthesia.
  
  
  METHODS
  Intubating conditions were evaluated according to the scoring system described by Viby-Mogensen et al. Successful intubation was defined as excellent or good.
  
  
  METHODS
  For induction of anesthesia, an intravenous (IV) bolus dose of propofol 2.0 mg/kg was given over 30 seconds followed by the administration of predetermined IV remifentanil over 30 seconds; intubation was performed 90 seconds after completion of the remifentanil administration. The dose of remifentanil used for each patient was determined by the response of the previously tested patients, using the modified Dixon's up-and-down method (using 0.2 μg/kg as a step size). The first patient was tested with remifentanil 1.0 μg/kg. If intubation failed, the remifentanil dose was increased by 0.2 μg/kg; if intubation was successful, the dose was decreased by 0.2 μg/kg. Mean arterial pressure (MAP), heart rate (HR), and peripheral oxygen saturation were recorded during the study period.
  
  
  RESULTS
  According to probit analysis, the effective dose of remifentanil in 50% (ED(50)) and 95% (ED(95)) of patients were 1.40 μg/kg and 2.40 μg/kg, respectively. Preintubation and postinduction HR and MAP values were lower than preinduction values (P < 0.001).
  
  
  CONCLUSIONS
  The optimal bolus dose of remifentanil for acceptable intubating conditions was 2.40 μg/kg (95% confidence interval, 1.90-9.0 μg/kg) in 95% of patients during induction of anesthesia with propofol 2.0 mg/kg without neuromuscular blocking agents.
authors: Department of Anaesthesiology, Bafra State Hospital, Bafra/Samsun, Turkey.
authors: Mustafa
authors: M
authors: Demirkaya
authors: Ebru
authors: E
authors: Kelsaka
authors: Binnur
authors: B
authors: Sarihasan
authors: Yüksel
authors: Y
authors: Bek
authors: Emre
authors: E
authors: Üstün
mesh_terms: D000328:Adult; D019162:Anesthetics, Combined / Q000008:administration & dosage*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods*; D008297:Male; D019148:Neuromuscular Blockade; D010880:Piperidines / Q000008:administration & dosage*; D015742:Propofol / Q000008:administration & dosage*; D000077208:Remifentanil; D055815:Young Adult
chemical_list: D019162:Anesthetics, Combined; D018686:Anesthetics, Intravenous; D010880:Piperidines; D000077208:Remifentanil; D015742:Propofol