A Comparison of Three Videolaryngoscopes for Double-Lumen Tubes Intubation in Humans. A Randomized Controlled Study

Several regional surveys among thoracic anesthesiologists showed that the double-lumen endobronchial tubes (DLT) is still the first choice for lung separation.[1-3] The introduction of videolaryngoscopes (VL) enables the use of the DLTs instead of a bronchial blockers for lung separation in patients with difficult airway.[4-5]

There are numerous VLs, including, stylets, channeled and traditional VLs. The GlideScope®-assisted DLT insertion (Verathon Inc., Bothell, WA, USA), has been associated with variable intubation durations according to the experience of the intubating operators, despite superior vocal cord views.[6-7] The channeled VL, like as the Airtraq® (Prodol Limited, Viscaya, Spain) and the standard non-channeled blade of the King Vision™ (KVL™) (King Systems, Indianapolis, IN, USA), may offer additional benefits for DLT intubation in patients with limited mouth opening or restricted neck movement, [8-10] in whom the use of traditional VL like as the Glidescope® could be difficult. This is because of the larger outer diameter, the distal curvature and the increased rigidity of the DLT.[11]

Of note, the longer intubation durations with the use of different VL-assisted DLT insertion could be shortened with building up the operator's experience.

Comparing the effects of the three studied VLs on the time to DLT intubation in humans has not yet been studied.

We hypothesize that time to successful DLT intubation using the channeled VL, namely, the Airtraq® and KVL™, will be shorter than with the Macintosh (MAC) laryngoscope and GlideScope® VL when used by non-expert anesthesiologists. We will compare the effects of the MAC, GlideScope®, Airtraq® and KVL™ on the time to DLT intubation, laryngoscopic view, ease of intubation, number of intubation attempts, and number of optimization maneuvers in patients undergoing thoracic procedures using DLTs for one-lung ventilation (OLV).