A comparison of endotracheal intubation characteristics between Macintosh, CMAC and Smart Trach laryngoscopes; A randomized prospective clinical trial.

BACKGROUND: In this study, we compared the performance characteristics of Macintosh laryngoscope, CMAC videolaryngoscope with a recently developed videolaryngoscope called Smart Trach.

RESEARCH DESIGN AND METHODS: : Three hundred seventy-five patients belonging to mixed population without having anticipated difficult airways undergoing elective surgeries were randomly allocated to be intubated using either of the three laryngoscopes (Macintosh, CMAC or Smart Trach). Time needed for successful intubation, number of attempts, Cormack Lehane's (CL) grading, optimisation maneuverers, intubation difficulty score (IDS), subjective ease of intubation (VAS), subjective lifting force and complications were recorded.

RESULTS: : Demographic and anthropometric measurements (sex, height, weight and body mass index) among the groups were comparable. CL grades, lifting force, IDS, VAS and intubation times (seconds) were significantly different whereas need for maneuver, attempts and complications were similar. (p>0.05 each). Intubation times (seconds) were significantly different between Macintosh [36(29-43) seconds] CMAC [30(24-37)] and Smart Trach [35(30-42] groups. (p<0.001). Subjective ease of intubation based on VAS score was lowest in Smart trach group [1(1-2)] (p<0.001).

CONCLUSION: Shortest intubation times were achieved with CMAC with least use of lifting force. First attempt success rates of were similar. Intubation was easiest subjectively using Smart Trach as manifested by lowest VAS and IDS.

TRIAL REGISTRATION: Clinical Trial registry of India (CTRI/2019/09/021279 dated 17/09/2019).