Introduction: Videolaryngoscopes facilitate the tracheal intubation by enabling anaesthetists to have a superior vision of the larynx with minimal manipulation of the oral-pharyngeal-laryngeal structures. Studies have indicated that video laryngoscopes improve the success rate of intubation and significantly reduce intubation difficulties. However, an improved view is not always an assurance of intubation success due to the nature of oral-pharyngeal-laryngeal axis. For this reason, Endotracheal tube be must be at an angle between 450 and 900 to enter the larynx.

Aim: This study was conducted to determine the optimal angles (between 600 and 900) of the stylet when using McGrath video laryngoscopes for the ease of intubation.

Methods: This study involved 100 patients of both male and female who were undergoing elective surgeries that required endotracheal intubation. The patients involved were aged between 19 years and 70 years. atients were indiscriminately divided into two equal groups, 50 patients for 600 (n=50) and 50 patients for 900 (n=50). This study excluded patients that required rapid sequence intubation; ASA III, IV, and V; patients that required emergency surgeries; and patients who had a scored four in the mallampati test. The following parameters Intubation time (Sec), Glottic opening Grade, Failure of First Attempt, Ease of Intubation, the presence of Bleeding were assessed. 

Results: Category variables were analyzed using the Chi-square test while continuous variables were analyzed using the independent t-test between 600 and 900 groups. All the selected 100 patients completed this study. All the patients in 600 group intubated successfully with 1st attempt and within 50 seconds. In contrast, intubation of six patients failed in the group 900.

Conclusion: The results of this study indicated that the level intubation difficulty and glottic grade were not significantly different between two groups.