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 significant hemodynamic stress response, which may be detrimental in certain patient populations. This study aimed to compare the hemodynamic response to laryngoscopy and intubation using the Macintosh and McCoy laryngoscope blades.Methods: In this randomized controlled trial, 60 patients undergoing general anesthesia were allocated to 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 after intubation, and at 1, 3, and 5 minutes post-intubation. The percentage change from baseline was calculated for each parameter and compared between the two groups.Results: The McCoy blade was associated with significantly lower percentage increases 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) immediately after intubation compared to the Macintosh blade. The hemodynamic parameters remained 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 attenuates the hemodynamic stress response to endotracheal intubation compared to the Macintosh blade in patients undergoing general anesthesia. These findings support the use of the McCoy blade as a preferred choice for minimizing hemodynamic perturbations during airway management.