Video laryngoscopy versus direct laryngoscopy for double-lumen endotracheal tube intubation: A retrospective analysis

Objective: The authors hypothesized that video laryngoscopy (VL) facilitated double-lumen tube (DLT) insertion compared with direct laryngoscopy (DL). Design: A retrospective analysis. Setting: An academic hospital. Participants: Patients older than 18 years of age undergoing thoracic surgery requiring DLT placement between 2005 and 2011. Interventions: Patients without airway predictors of difficult intubation who were intubated under DL with Macintosh (DL-MAC, n = 40) or Miller (DL-MIL, n = 44) blades and VL with McGrath MAC (Aircraft Medical, Edinburgh, UK) and C-MAC (Karl Storz, Tuttlingen, Germany) laryngoscopes (n = 46) were included in the study. Patients who were intubated with both VL devices were grouped into a VL group. Measurements: Patients in all 3 groups had comparable preoperative demographics. Mallampati scores and ease of manual ventilation after the induction of anesthesia were also similar in all groups. The Cormack Lehane (C-L) grade views were significantly higher in patients in the DL-MAC than in the DL-MIL and VL groups (p < 0.006). The number of intubation attempts was similar in all 3 groups; however, the percentage of intubation reported to be difficult was higher in the DL-MAC than in the other 2 groups (p = 0.014). No damage to the airway was found in any of the groups. Conclusion: DLT placement using VL appeared to overcome some of the limitations of DL-MAC but was similar to DL-MIL. The authors speculated that the ease of placement was related to the improved visualization of the vocal cords because there was a significantly greater number of C-L views 3 and 4 in the DL-MAC group as compared with the VL and DL-MIL groups. Hence, the authors advocate using VL, particularly when the laryngoscopist is inexperienced using DL-MIL for DLT placement.