title: The safety and efficacy of alfentanil-based induction in bronchoscopy sedation: A randomized, double-blind, controlled trial.
abstract: BACKGROUND
  Alfentanil in combination with propofol produces a synergistic sedative effect in patients undergoing flexible bronchoscopy (FB). However, the use of this combination is controversial due to the risk of cardiopulmonary depression. The aim of this study was to evaluate the proper induction regimen of alfentanil in propofol target-controlled infusion for FB sedation.
  
  
  METHODS
  One hundred seventy-three patients were assigned randomly into 5 regimens: Group 1 and 2, alfentanil 2.5 and 5 μg/kg, respectively, immediately before propofol administration; Group 3 and 4, alfentanil 2.5 and 5 μg/kg, respectively, 2 minutes before propofol administration; and Group 5, propofol administration alone to achieve the observer assessment of alertness and sedation scale 3∼2. The bronchoscopists, physicians in charge of sedation, and patients were blind to the regimens. Adverse events, drug dose, induction, procedure and recovery time, cough severity, and propofol injection related pain were recorded.
  
  
  RESULTS
  The patients in groups 2 and 4 required a lower dose of propofol (P = 0.031 and 0.019, respectively) and shorter time (P = 0.035 and 0.010) than group 5 for induction. Patients in group 2 experienced more hypoxemia than those in group 5 during induction (P = 0.031). The physician in charge of sedation scored a lower severity of cough in the patients in group 4 than in groups 3 and 5. There were no differences in terms of propofol injection related pain among the groups.
  
  
  CONCLUSIONS
  Alfentanil 5 μg/kg given immediately before propofol infusion cannot be recommended. Further study is required to define conclusions about alfentanil 2.5 and 5 μg/kg because of the low power rating of subgroup in the present study.
authors: Department of Thoracic Medicine, Chang Gung Memorial Hospital Linkou Branch Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University Healthcare Center, Chang Gung Memorial Hospital, Taoyuan Department of Thoracic Medicine, Ton-Yen General Hospital, Hsinchu County, Taiwan.
authors: Chung-Hsing
authors: CH
authors: Hsieh
authors: Ting-Yu
authors: TY
authors: Lin
authors: Tsai-Yu
authors: TY
authors: Wang
authors: Chih-Hsi
authors: CH
authors: Kuo
authors: Shu-Min
authors: SM
authors: Lin
authors: Han-Pin
authors: HP
authors: Kuo
authors: Yu-Lun
authors: YL
authors: Lo
mesh_terms: D015760:Alfentanil / Q000008:administration & dosage*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D001999:Bronchoscopy / Q000379:methods*; D016292:Procedural Sedation / Q000379:methods*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015742:Propofol / Q000008:administration & dosage; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D018686:Anesthetics, Intravenous; D015760:Alfentanil; D015742:Propofol