A Comparative Study of Laryngoscopic View and Intubation Response using Macintosh, McCoy and AirTraq Laryngoscopes in Adults Undergoing Elective Surgeries

Abstract

Context: Laryngoscopes are most commonly used for endotracheal intubation. It plays an important role in securing airway in emergency conditions and in administration of general anesthesia. They range from simple rigid scopes with a light bulb to complex fiber optic video devices. Objectives: The purpose of the study was tocompare laryngoscopy and intubating conditions in three groups of patients using Macintosh, McCoy and Airtraq laryngoscope:Visualisation of pharyngeal structures and larynx as per Modified Cormack and Lehane grading; Hemodynamics; Adverse effects, if any. Settings and Design: Randomised prospective comparative study. Methods and Material: after obtaining ethical committee approval, 90 adult patients of either sex, aged between 18 to 60 years, of physical status ASA Grade I and Grade II undergoing elective surgeries under general anesthesia after obtaining written informed consent were included. Divided into 3 groups of 30 each and randomly allocated. Group I -Patients intubated with Macintosh laryngoscope (n-30); Group II - Patients intubated with Airtraq optical laryngoscope (n-30); Group III -Patients intubated with McCoy laryngoscope (n-30). The laryngoscopy view obtained was compared according to Cormack and Lehane grading. The change in systolic, diastolic, mean arterial pressure, pulse rate and SpO2 will be recorded at pre-induction, pre-intubation and post intubation at 1, 3 and 5 minutes. Statistical analysis used: The demographic data was analysed using descriptive statistics and expressed as mean ± standard deviation. Categorical data was analyzed by chi square test. P value of 0.05 or less was considered statistically significant. Results: Airtraq laryngoscope improved the Cormack and Lehane glottic view compared with the McCoy and Macintosh laryngoscopes. The maximum change in HR was 24% in the Macintosh, 2.27% in the Airtraq and 11.9% in the McCoy group, and increase mean arterial pressure was 20.63% in the Macintosh, 4.37% in the Airtraq and 7.37% in the McCoy group. This difference between the three groups was significant (P <0.0001). Conclusions: From the present study, it is concluded that Airtraq optical laryngoscope provides a better glottic exposure and triggers minimal hemodynamic response to laryngoscopy and intubation when compared to Macintosh and McCoy.