Sedation during flexible bronchoscopy in patients with pre-existing respiratory failure: Midazolam versus Midazolam plus Alfentanil

Respiration. 2010;79(4):307-14. doi: 10.1159/000267227. Epub 2009 Dec 14.


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.

Objectives: 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.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Alfentanil / administration & dosage*
  • Alfentanil / adverse effects
  • Anesthesia Recovery Period
  • Anesthetics, Intravenous / administration & dosage*
  • Anesthetics, Intravenous / adverse effects
  • Blood Gas Monitoring, Transcutaneous
  • Bronchoscopy*
  • Carbon Dioxide / blood
  • Female
  • Heart Rate
  • Humans
  • Male
  • Midazolam / administration & dosage*
  • Midazolam / adverse effects
  • Middle Aged
  • Oxygen / blood
  • Respiratory Insufficiency / blood*


  • Anesthetics, Intravenous
  • Carbon Dioxide
  • Alfentanil
  • Midazolam
  • Oxygen