Comparison of Direct and Video Laryngoscopes during Different Airway Scenarios Performed by Experienced Paramedics: A Randomized Cross-Over Manikin Study

Introduction. Airway management plays an essential role in anaesthesia practice, during both elective and urgent surgery procedures and emergency medicine. Aim. The aim of the study was to compare Macintosh laryngoscope (MAC), McGrath, and TruView PCD in 5 separate airway management scenarios. Methods. This prospective cross-over simulation study involved 93 paramedics. All paramedics performed intubation using direct laryngoscope (MAC), McGrath, and TruView PCD video laryngoscopes. The study was performed in 5 different scenarios: (A) normal airway, (B) tongue oedema, (C) pharyngeal obstruction, (D) cervical collar stabilization with tongue oedema, and (E) cervical collar stabilization with pharyngeal obstruction. Results. In scenario A, the success rate was 99% with MAC, 100% with McGrath, and 94% with PCD. Intubation time was 17 s (IQR: 16-21) for MAC, 18 s (IQR: 16-21) for McGrath, and 27 s (IQR: 23-34) for PCD. In scenario B, the success rate was 61% with MAC, 97% with McGrath, and 97% with PCD (p<0.001). Intubation time was 44 s (IQR: 24-46) for MAC, 22 s (IQR: 20-27) for McGrath, and 39 s (IQR: 30-57) for PCD. In scenario C, the success rate with MAC was 74%, 97% with McGrath, and 72% with PCD (p<0.001). Intubation time was 21 s (IQR: 19-29) for MAC, 18 s (IQR: 18-24.5) for McGrath, and 30 s (IQR: 23-39) for PCD. In scenario D, the success rate with MAC was 32%, 69% with McGrath, and 58% with PCD (p<0.001). Intubation time was 26 s (IQR: 20-29) for MAC, 26 s (IQR: 20-29) for McGrath, and 45 s (IQR: 33-56) for PCD. In scenario E, the success rate with MAC was 32%, but 64% with McGrath and 62% with PCD (p<0.001). Intubation time was 28 s (IQR: 25-39) for MAC, 19 s (IQR: 18-26) for McGrath, and 34 s (IQR: 27-45) for PCD. Conclusions. The McGrath video laryngoscope proved better than Truview PCD and direct intubation with Macintosh laryngoscope in terms of success rate, duration of first intubation attempt, number of intubation attempts, Cormack-Lehane grade, percentage of glottis opening (POGO score), number of optimization manoeuvres, severity of dental compression, and ease of use.