McGrath MAC video laryngoscope versus direct laryngoscopy for the placement of double-lumen tubes: A randomised control trial.

BACKGROUND AND AIMS: Role of video laryngoscopes (VLs) in the management of difficult airway with single-lumen tubes (SLTs) is established. VLs provide improved glottis view but are associated with longer time to intubate (TTI). We aimed to compare the TTI for double-lumen tube (DLT) insertion using the McGrath® MAC VL versus direct Macintosh laryngoscope (DL).

METHODS

Eleven senior anaesthesiologists experienced in SLT insertion, but not DLT insertion with VL participated. Seventy-four adults belonging to American Society of Anesthesiologists physical status I-II posted for elective surgery needing lung isolation were randomised to both intubator and laryngoscope (VL/DL). Primary endpoint was TTI; secondary endpoints included glottic view assessed by the Cormack and Lehane (CL) grade, need for external laryngeal manipulation, ease of intubation [scored using Numeric Rating Scale (1 - easiest, 10 - most difficult)] and associated complications. TTI was compared using Student's t-test.

RESULTS

No difference was found in TTI with DL and VL [(56.6 ± 14) s vs (64.4 ± 24) s, P = 0.104] as well as ease of use of laryngoscope [median score of 2 (1-3) in both]. Use of VL resulted in more patients with CL I glottic view - 86.0% versus 58.0% (P = 0.007). Fewer patients required external laryngeal manipulations (19% vs 47%, P = 0.013), and complications were fewer in the VL group (5% vs 24%, P = 0.023).

CONCLUSION

TTI for DLT insertion was similar with VL and DL. However, VL was associated with better glottis visualisation, reduced need of external laryngeal manipulation and fewer complications.