title: Sedation during flexible bronchoscopy in patients with pre-existing respiratory failure: Midazolam versus Midazolam plus Alfentanil.
abstract: BACKGROUND
  The use of sedation during flexible bronchoscopy (FB) is undisputed; however, the combination of benzodiazepines and opiates, although reasonable, is suggested to cause hypoventilation, particularly in patients with pre-existing respiratory failure.
  
  
  OBJECTIVE
  To assess respiratory function during FB.
  
  
  METHODS
  Transcutaneous PCO(2 )(PtcCO(2)), oxygen saturation, patients' tolerance, time after FB until recovery and application of drug dosage were assessed in patients receiving either midazolam with alfentanil (n = 15) or midazolam alone (n = 15) for sedation for FB.
  
  
  RESULTS
  There were no differences in PtcCO(2) values during FB between the two groups (all p > 0.05). However, PtcCO(2 )significantly increased over time in both groups (both p < 0.001; RM-ANOVA on ranks). Minimum oxygen saturation (SaO(2)) [89 (interquartile range 79.8/92.8) vs. 86 (interquartile range 82.3/87.8)%; p = 0.46] and the duration until recovery, i.e., achieving an ALDRETE score of > or =9 [30 (interquartile range 10/90) vs. 10 (interquartile range 10/105) min; p = 0.68] were comparable for monosedation and combined sedation, respectively. The total amount of midazolam [4.0 (interquartile range 4.0/4.0) vs. 2.0 (interquartile range 2.0/2.0) mg; p < 0.001] was lower in patients receiving combined sedation. Significantly lower scores for pain and asphyxia, and a clear tendency to less nausea and cough were reported by patients receiving combined sedation.
  
  
  CONCLUSIONS
  Combined sedation during FB produced a comparable degree of desaturation and hypoventilation, and is associated with a comparable time to full recovery compared to monosedation in patients with pre-existing respiratory failure. Importantly, FB using combined sedation is better tolerated by patients despite only 50% midazolam consumption.
authors.affiliation: Department of Pneumology, University Hospital, Freiburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Dreher
authors.forename: Emelie
authors.initials: E
authors.lastname: Ekkernkamp
authors.forename: Jan Hendrik
authors.initials: JH
authors.lastname: Storre
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Kabitz
authors.forename: Wolfram
authors.initials: W
authors.lastname: Windisch
mesh_terms: D000328:Adult; D000368:Aged; D015760:Alfentanil / Q000008:administration & dosage* / Q000009:adverse effects; D000762:Anesthesia Recovery Period; D018686:Anesthetics, Intravenous / Q000008:administration & dosage* / Q000009:adverse effects; D001785:Blood Gas Monitoring, Transcutaneous; D001999:Bronchoscopy; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008874:Midazolam / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D012131:Respiratory Insufficiency / Q000097:blood*
chemical_list: D018686:Anesthetics, Intravenous; D002245:Carbon Dioxide; D015760:Alfentanil; D008874:Midazolam; D010100:Oxygen