Comparison of the McGrath videolaryngoscope and the Macintosh laryngoscope for double lumen endobronchial tube intubation in patients with manual in-line stabilization: A randomized controlled trial

Background:Double lumen endobronchial tube (DLT) intubation is commonly used for one-lung ventilation in thoracic surgery. However, because of its large size and shape, it is difficult to perform intubation compared with a single lumen tube. The aim of this randomized controlled trial was to determine whether the McGrath videolaryngoscope has any advantage over the direct Macintosh laryngoscope for DLT intubation in patients with a simulated difficult airway.Methods:Forty-four patients (19-60 years of age); scheduled to undergo general anesthesia with one-lung ventilation were assigned to 1 of 2 groups: DLT intubation with the McGrath videolaryngoscope (ML group [n=22]); or conventional Macintosh laryngoscope (DL group [n=22]). After manual in-line stabilization was applied as a way of simulating a difficult airway, the time required for intubation and the quality of glottic view were evaluated.Results:The time to successful intubation was not different between the 2 groups (ML group, 45 s [interquartile range, 38-52 s] versus DL group, 54 s [45-59 s]; P=.089). The McGrath videolaryngoscope, however, provided a significantly better glottic view. Modified Cormack and Lehane grade was better (P<.001), and the percentage of glottis opening score was higher in the ML group (P<.001). Overall intubation difficulty scale score was lower in the ML group (1 [0-2]) versus the DL group (3 [2-4]) (P<.001).Conclusion:The McGrath videolaryngoscope improved glottic view and resulted in lower overall intubation difficulty scale score in patients with in-line stabilization.