Evaluation of the efficacy and safety of a video-assisted lighted stylet (StyletView)‎ as a modality in the management of a difficult airway

Abstract EN

Background Many devices have been developed to facilitate intubation in cases of difficult direct laryngoscopy.

Visualization of the vocal cords with these devices is achieved using either an optical or a video system.

This study was carried out to evaluate the efficacy and safety of a video-assisted lighted stylet (StyletView) in comparison with the classical direct laryngoscopy with a Macintosh blade in the management of patients with grades 3 and 4 difficult airway.

Methods This study included 80 adult patients who came to National Cancer Institute for elective cancer surgeries under general anesthesia with grade 3 and 4 difficult intubation according to the Cormack and Lehane classification.

They were randomized into two equal groups: the Macintosh (M) group and the StyletView (S) group.

Both groups were compared according to the rate of success of intubation by each device, the time taken to complete intubation in seconds, the number of patients who required external laryngeal pressure, the degree of intubation difficulty, number of failures, and attempts before successful intubation.

The mean pulse rate and the mean arterial blood pressure were determined just before the first attempt of intubation as a baseline reading and just after successful intubation.

The adverse effects (hypoxemia during intubation, sore throat, hoarseness of voice, dental and lip trauma, and oropharyngeal bleeding) were recorded.

Results The rate of success of intubation was significantly higher in the S group (95%) compared with the M group (80%).

The mean time taken for complete intubation in seconds was significantly less in the S group (34± 8.9) compared with the M group (64.1 ± 10.2).

The number of patients who required external laryngeal pressure was significantly less in the S group (four patients) compared with the M group (12 patients).

The median degree of intubation difficulty was significantly less in the S group (2) compared with the M group (6).

The number of patients intubated successfully at the first attempt was significantly higher in the S group than those in the M group.

The number of patients who required three attempts to be intubated was significantly higher in the M group than that in the S group, and four patients in the M group were intubated at the fourth attempt, whereas none of the successfully intubated patients in the S group required this fourth attempt.

The mean heart rate and the mean arterial blood pressure immediately after successful intubations were significantly higher in the M group compared with the baseline and compared with those in the S group.

The incidence of adverse effects of hypoxemia during intubation, sore throat, hoarseness of voice, and dental and lip trauma was significantly higher in the M group than in the S group.

Conclusion The StyletView provides a simple and cost-effective solution in various elective surgeries where difficult intubation is anticipated and helps to avoid the need for multiple trials by the Macintosh blade as it allows visualization of the glottic opening and tracheal rings and hence decreases the incidence of complications that may occur in difficult intubation.