title: Comparison of Bullard and Airtraq laryngoscopes with conventional laryngoscopy in a manikin study of simulated difficult intubation.
abstract: BACKGROUND
  When airway management is difficult, various measures can be taken to facilitate tracheal intubation. The Bullard and Airtraq laryngoscopes were developed for this purpose. We hypothesised that the Bullard and Airtraq laryngoscopes would perform better than a conventional laryngoscope in the management of a simulated difficult airway. We also hypothesised that the indirect laryngoscopes would perform comparably.
  
  
  METHODS
  In a randomised controlled study, 60 anaesthetists (30 with no or little experience and 30 with broader experience in the use of the Bullard laryngoscope, referred to as beginners and experts, respectively) performed three successive intubation attempts using conventional, Bullard and Airtraq laryngoscopes in two simulated difficult airway scenarios: neck immobilisation (scenario A) and neck immobilisation with additional tongue oedema (scenario B). The primary endpoint was overall intubation success rate. Secondary endpoints were time required for successful intubation, the amount of dental stress exerted during laryngoscopy and satisfaction with each airway device.
  
  
  RESULTS
  In scenario A, intubation success rates were 97-100% with all devices. In scenario B, all participants failed to intubate the trachea using the conventional laryngoscope. When using the Bullard laryngoscope, intubation success rates of 87-97% did not differ significantly (P > 0.05) from those during scenario A and between groups (beginners vs. experts). In contrast, when using the Airtraq laryngoscope, the overall intubation success rate was significantly lower (P < 0.05) compared with scenario A and compared with use of the Bullard laryngoscope, and differed between beginners and experts (20 and 50%, respectively). In cases of successful intubation, intubation times were comparable between devices and groups. Intubation times were longer during scenario B. Dental stress was always lower (P < 0.05) during use of the Bullard and Airtraq laryngoscopes compared with the conventional laryngoscope, lowest (P < 0.05) during use of the Bullard laryngoscope and (with the exception of use of the conventional laryngoscope by the experts) higher during scenario B than during scenario A. In scenario A, participants preferred both video laryngoscopes to the conventional laryngoscope.
  
  
  CONCLUSIONS
  In a moderately difficult airway scenario, all laryngoscopes performed equally well. However, in a more difficult airway scenario, the Bullard and Airtraq laryngoscopes performed better than the conventional laryngoscope, with the Bullard device performing better than the Airtraq. This may be in part related to differing prior experiences of operators with the respective airway devices.
authors.affiliation: Department of Anaesthesia and Critical Care Medicine, University Medical Centre Freiburg, Freiburg, Germany.
authors.forename: Maria A-L
authors.initials: MA
authors.lastname: Legrand
authors.forename: Daniel
authors.initials: D
authors.lastname: Steinmann
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Priebe
authors.forename: Georg
authors.initials: G
authors.lastname: Mols
mesh_terms: D000758:Anesthesia / Q000379:methods*; D002983:Clinical Competence; D003198:Computer Simulation; D004867:Equipment Design; D006801:Humans; D007440:Intubation; D007442:Intubation, Intratracheal / Q000295:instrumentation; D020704:Laryngoscopes; D007828:Laryngoscopy / Q000379:methods*; D008348:Manikins; D015203:Reproducibility of Results; D014132:Trachea / Q000473:pathology