Videolaryngoscopy versus direct laryngoscopy for double-lumen endotracheal tube intubation in thoracic surgery - a randomised controlled clinical trial.

BACKGROUND: Double-lumen tube (DLT) intubation is necessary for thoracic surgery and other operations with the need for lung separation. However, DLT insertion is complex and might result in airway trauma. A new videolaryngoscopy (GVL) with a thin blade might improve the intubation time and reduce complexity as well as iatrogenic airway complications compared to conventional direct laryngoscopy (DL) for DLT intubation. METHODS: A randomised, controlled trial was conducted in 70 patients undergoing elective thoracic surgery using DLT for lung separation. Primary endpoint was time to successful intubation. The secondary endpoints of this study were number of intubation attempts, the assessment of difficulty, any complications during DLT intubation and the incidence of objective trauma of the oropharynx and supraglottic space and intubation-related subjective symptoms. RESULTS: 65 patients were included (DL group [n  =  31], GVL group [n  =  34]). Median intubation time (25th-75th percentiles) in GVL group was 93 s (63-160) versus 74 (58-94) in DL group [p = 0.044]. GVL resulted in significantly improved visualisation of the larynx (Cormack and Lehane grade of 1 in GVL group was 97% vs. 74% in DL Group [p = 0.008]). Endoscopic examinations revealed significant differences in GVL group compared to DL group showing less red-blooded vocal cord [p = 0.004], vocal cord haematoma [p = 0.022] and vocal cord haemorrhage [p = 0.002]. No significant differences regarding the postoperative subjective symptoms of airway were found. CONCLUSIONS: Videolaryngoscopy using the GlideScope®-Titanium shortly prolongs DLT intubation duration compared to direct laryngoscopy but improves the view. Objective intubation trauma but not subjective complaints are reduced. TRIAL REGISTRATION: German Clinical Trial Register DRKS00020978, retrospectively registered on 09. March 2020.