Comparison of Macintosh and McCoy Laryngoscope Blades in Eliciting Stress Response during General Anaesthesia: A Study at a Tertiary Health Centre, Bangalore

Background: Endotracheal intubation during general anesthesia can elicit a significanthemodynamic stress response, which may be detrimental in certain patient populations.This study aimed to compare the hemodynamic response to laryngoscopy andintubation using the Macintosh and McCoy laryngoscope blades.Methods: In thisrandomized controlled trial, 60 patients undergoing general anesthesia were allocatedto either the Macintosh (n=30) or McCoy (n=30) group. Hemodynamic parameters,including heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure(DBP), and mean arterial pressure (MAP), were recorded at baseline, immediately afterintubation, and at 1, 3, and 5 minutes post-intubation. The percentage change frombaseline was calculated for each parameter and compared between the twogroups.Results: The McCoy blade was associated with significantly lower percentageincreases in HR (12.20% vs. 25.00%, p<0.001), SBP (6.78% vs. 15.00%, p=0.002),DBP (6.41% vs. 10.00%, p=0.01), and MAP (6.59% vs. 12.90%, p<0.001) immediatelyafter intubation compared to the Macintosh blade. The hemodynamic parametersremained significantly lower in the McCoy group at 1, 3, and 5 minutes post-intubation(p<0.05 for all comparisons).Conclusions: The McCoy laryngoscope blade attenuatesthe hemodynamic stress response to endotracheal intubation compared to theMacintosh blade in patients undergoing general anesthesia. These findings support theuse of the McCoy blade as a preferred choice for minimizing hemodynamicperturbations during airway management.