Comparison of results from novice and trained personnel using the Macintosh laryngoscope, Pentax AWS®, C-MAC™ and Bonfils intubation fibrescope: a manikin study

Indirect laryngoscopes offer improved laryngeal view and higher success rates of intubation, particularly for difficult airways. We hypothesised that: (a) the time required for intubation, overall success rates and ease of intubation with indirect laryngoscopes would be better than with the Macintosh laryngoscope; and (b) novices may achieve higher success rates and intubate faster using indirect laryngoscopes. In a cross-sectional observational study, 13 novices and 13 skilled anaesthetists were recruited. Participants were compared when intubating a manikin simulating normal and difficult airway scenarios using the Macintosh laryngoscope, Pentax Airway Scope® (AWS), C-MAC[TM] and Bonfils intubation fibrescope. There was no significant difference in intubation success rates between the groups. Skilled anaesthetists intubated faster than novices with Pentax AWS in the difficult airway scenario (22 s vs. 33 s, p = 0.047). The mean intubation times for C-MAC and Pentax AWS were shorter than for the Macintosh laryngoscope and Bonfils intubation fibrescope in both difficult (C-MAC: 24 s, Pentax AWS: 28 s, Macintosh: 80 s, Bonfils: 61 s; p < 0.001) and normal (C-MAC: 17 s, Pentax AWS: 19 s, Macintosh: 39 s, Bonfils: 38 s; p = 0.002) airway scenarios. We found that intubation success was more than 85% with all indirect laryngoscopes compared to 69% for the Macintosh laryngoscope. Both C-MAC and Pentax AWS achieved faster intubation times compared to the Macintosh laryngoscope and Bonfils intubation fibroscope for both airway scenarios. Skilled anaesthetists were 33% faster than novices when intubating a difficult airway using Pentax AWS.