Comparison of C-MAC ® conventional blade, D-Blade ™ , and Macintosh laryngoscopes for endotracheal intubation in patients with simulated immobilization using manual in-line stabilization: A randomized trial.

Background: A difficult airway is anticipated with cervical spine injuries (CSIs) as immobilization techniques such as manual in-line stabilization (MILS) are used, which distort the oro-pharyngeal-laryngeal axis. Video laryngoscopes (VLs) make difficult airway management easy, as they do not require axis alignment. The present study aimed to compare the total time taken by Macintosh laryngoscope (ML), conventional blade, and D-blade ™ of C-MAC ® VL in simulated CSI scenarios using MILS.

Methods: Ninety patients were randomly allocated into three groups: Group M (ML), Group C (conventional blade of C-MAC ® ), and Group D (D-blade ™ of C-MAC ® ) with MILS applied before intubation. Primary outcome was the total time taken for successful intubation, while secondary outcomes were to assess Cormack-Lehane (CL) grade, number of attempts, hemodynamic response, and associated complications.

Results: Total time for intubation in Group C was 23.40 ± 7.06 sec compared to 35.27 ± 6.53 and 47.27 ± 2.53 sec in groups D and M, respectively ( P < 0.001). CL-grade I was observed in 15/30 (50%) in Group M, 25/30 (83.3%) in Group C, and 29/30 (96.7%) in Group D. Group M reported 7/30 (23.3%) failed intubations, while none were observed in other groups. Hemodynamic parameters were significantly higher at 3 and 5 min in Group M. Postoperative sore throat was recorded in 12/30 (40%) in Group M compared to 3/30 (10%) in groups C and D each ( P value 0.037).

Conclusion: C-MAC ® VL requires less time for intubation, provides better glottic view, and has higher success, with better attenuation of hemodynamic response and fewer complications compared to ML.