A comparison of macintosh and airtraq laryngoscopes for endotracheal intubation in adult patients with cervical spine immobilization using manual in line axial stabilization: A prospective randomized study

Background: During cervical spine immobilization using Manual In Line Axial Stabilization (MILS), it is difficult to visualize the larynx by aligning the oropharyngeolaryngeal axes using Macintosh laryngoscope. Theoretically, Airtraq an anatomically shaped blade with endotracheal tube guide channel offers advantage over Macintosh. We hypothesized that intubation would be easier and faster with Airtraq compared with Macintosh laryngoscope. Materials and Methods: Ninety anesthetized adult patients with normal airways were intubated by experienced anesthesiologists after cervical immobilization with MILS either with Macintosh or Airtraq. Primary outcomes compared were successful intubation, and degree of difficulty of intubation as assessed by Intubation Difficulty Scale (IDS) score. Secondary outcomes compared were duration of laryngoscopy and intubation, degree of difficulty of intubation as assessed by Numerical Rating Scale score, soft tissue, and dental trauma. Results: All 90 patients were successfully intubated in the first attempt. Intubation as assessed by IDS score was easier in Airtraq (84.44%) in contrast to slight difficulty in the Macintosh (77.78%) group; Numerical Rating Scale score was easy in both the groups (Airtraq-91.12%; Macintosh-93.34%). The median (interquartile range [IQR]) time for laryngoscopy, (12 s [IQR, 8 to 17.5) vs. 8 s [IQR, 6 to 12]); total duration for intubation (25 s [IQR, 20-33] vs. 22 s [IQR, 18-27.5]) were prolonged in Airtraq group in comparison to Macintosh group. Conclusions: In anesthetized adult patients with MILS compared with Macintosh, Airtraq provides equal success rate of intubation, statistically significant (although clinically insignificant) longer duration for laryngoscopy and intubation. Intubation with Airtraq was significantly easier than Macintosh as assessed by the IDS score.