The impact of videolaryngoscopy on the depth of endotracheal tube placement and the rate of unintended endobronchial intubation - a prospective randomized study Background and goal of the study

Background and goal of the study: Suboptimal visualisation of laryngeal structures could be associated with improper tracheal tube position or local airway trauma. The goal of this study was to compare the initial depth of tracheal tube insertion, rates of unintended endobronchial intubation, and postoperative patient discomfort after tracheal intubation using either videolaryngoscopy (GlideScope Titanium) or direct laryngoscopy (Macintosh blade). Type of study: Prospective, randomized, open study. Setting: Operating theatres of the University Hospital. Materials and methods: Ninety adult ASA I - III patients scheduled for elective neurosurgical procedures were randomized into the direct laryngoscopy (C) and videolaryngoscopy (V) groups. Exclusion criteria included cervical spine surgery, planned postoperative ventilation and history of tracheal, laryngeal and cervical spine surgery. Intubation time, initial depth of tracheal tube insertion, tube position corrections due to signs of endobronchial intubation and sings of postextubation discomfort were recorded. Results are expressed as mean +/- SD, mean (IQR) or as a percentage. Results and discussion: There was a higher initial depth of tube placement (21 [ 20;22] cm vs. 22 [21;23] cm, P = 0.010) and a higher rate of endobronchial intubation (15.6% vs. 0.0%, P = 0.012) in the C group in comparison to the V group. There were no differences in postoperative rates of soar throat (20.0%, vs. 17.8%, P = 1.000), hoarseness (31.1% vs. 24.4%, P = 0.488), patient height (172.7 +/- 10.3 vs. 173.5 +/- 8.7 cm, P = 0.692) or male:female ratio (24/45 vs 19/45, P = 0.165) between groups. Conclusion: The use of videolaryngoscopy is associated with a lower initial depth of tracheal tube insertion and a lower rate of unintended endobronchial intubation.