Laryngoscopic View and Ease of Intubation: A Comparison of McCoy, Macintosh and Airtraq Laryngoscopes in Predicted Difficult Airway

Abstract

Difficult airway management using direct laryngoscopes such as McCoy and Macintosh for tracheal intubation, remains a challenge to the Anaesthetist due to difficulty in alignment of the oral, pharyngeal and laryngeal axes. The Airtraq, a video laryngoscope, reduces this difficulty, improving laryngoscopic view and ease of intubation. This study sought to compare laryngoscopic view, ease of intubation and haemodynamic changes using McCoy, Macintosh as well as Airtraq Laryngoscopes in adult patients with predicted difficult airway. After obtaining ethical clearance, 93 consenting adult patients with predicted difficult airway requiring general anaesthesia with endotracheal intubation were randomly assigned to these three groups. Laryngoscopic view, ease of intubation and haemodynamic changes during laryngoscopy and intubation were assessed and recorded. The study participants were comparable across the study groups. There was a significant statistical difference in laryngoscopic view between study groups with thirty (96.8%) patients in the Airtraq group having Cormack and Lehane (CL) grade 1, compared to thirteen (41.9%) patients in the McCoy group and the Macintosh group having nine (29.0%) patients (p=0.001). The ease of intubation showed that 28 (90.3%), 11(35.5%) and 8(25.8%) patients in the Airtraq, McCoy and Macintosh groups respectively had an IDS score of 0 (p=0.001). The Airtraq laryngoscope was superior to both the McCoy and Macintosh laryngoscopes in improving laryngoscopic view and ease of intubation. The haemodynamic changes due to laryngoscopy and intubation were comparable among the three groups.