A comparative study of hemodynamic stress response to laryngoscopy with McCoy blade versus Macintosh blade in patients undergoing elective surgeries under general anesthesia

Abstract

Background & objective: Endotracheal intubation is considered the gold standard for airway management. It has been shown that different types of laryngoscope blades effect the hemodynamic response differently. We evaluated hemodynamic stress response before, during and after laryngoscopy with McCoy and Macintosh laryngoscope blades.

Methodology: A total of 68 patients were enrolled in the study and randomly allocated to the two study groups using computer-generated random numbers. Patients undergoing endotracheal intubation using the MacIntosh blade were labelled as Group MI, and those in which McCoy blade was used, were labelled as Group MC. Endotracheal tube placement and anesthesia maintenance were standardized for both study groups. The hemodynamic parameters, including heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were recorded before induction, before laryngoscopy, and at 1, 2, 3, 4, 5 and 10 min after laryngoscopy.

Results: The groups were comparable in terms of age and body mass index with similar mean values in the two studies and also concerning the ASA physical status and Mallampati classification. All the hemodynamic parameters, including HR, SBP, DBP, and MAP increased after laryngoscopy and intubation in both the study groups, but McCoy laryngoscope showed significantly lower values of SBP, DBP, and MAP at 1st and 2nd min after intubation.

Conclusion: McCoy's laryngoscope may be advantageous when compared to the Macintosh blade in situations where minimizing hemodynamic responses is crucial.

Abbreviations: DBP: diastolic blood pressure; MAP: mean arterial pressure: SBP: systolic blood pressure

Keywords: Airway management; Endotracheal intubation; Hemodynamic stress response; Laryngoscopy; McCoy blade; MacIntosh blade

Citation: Arpitha R, Divakar SR, Kiran AV, Yuvashri M. A comparative study of hemodynamic stress response to laryngoscopy with McCoy blade versus Macintosh blade in patients undergoing elective surgeries under general anesthesia. Anaesth. pain intensive care 2024;28(2):259−264; DOI: 10.35975/apic.v28i2.2362

Received: December 14, 2023; Revised: January 28, 2024; Accepted: February 17, 2024