Comparison of ease of intubation using McCoy laryngoscope and CMAC videolaryngoscope in modified Mallampati grade III and IV patients

Abstract

Background and Aims: Videolaryngoscopy has been introduced for the management of difficult airway; however, it remains unclear whether it is helpful in routine prediction of a difficult airway. The aim of our study was to compare the ease of intubation using a McCoy laryngoscope and CMAC® videolayngoscope using the Adnets Intubation Difficulty Scale (IDS) score in an anticipated difficult airway (modified Mallampati grade III and grade IV). Methods: Sixty patients belonging to the American Society of Anaesthesiologists physical status I, II, or III with modified Mallampati grade III and IV undergoing elective surgeries requiring tracheal intubation were randomly allocated into the McCoy group (n = 30) and CMAC® videolaryngoscope group (n = 30). The primary outcome of the study was to compare the ease of intubation between the McCoy laryngoscope and CMAC® videolaryngoscope using Adnet's Intubation Difficulty Scale (IDS) score. Secondary outcomes included time for glottic visualization, time to intubation, total intubation time, hemodynamic and any adverse events. Results: Comparison of both groups showed that CMAC® videolaryngoscope had a significantly (P = 0.028) lower IDS score (1.667) compared to the McCOY laryngoscope (2.467). Time to view glottis (P = 0.002), time to intubate (P = 0.009), and total intubation time (P = 0.002) were significantly prolonged with CMAC® videolaryngoscope compared to the McCoy laryngoscope. There was no difference in the hemodynamic response and adverse events between the groups. Conclusion: Our study concludes that although the time to intubate was prolonged in CMAC® videolaryngoscopy, the ease of intubation was better with CMAC videolaryngoscope compared to the McCoy laryngoscope. Hence, we suggest CMAC® videolaryngoscope for anticipated difficult tracheal intubation.