Abstract
Background: The aerosol box was designed to prevent cough droplets from spreading, but it can impede tracheal intubation. We tested the hypothesis that the C-MAC® video laryngoscope (C-MAC) with an external display is more useful than the i-view™ video laryngoscope (i-view) with an integrated display, or a Macintosh direct laryngoscope (Macintosh) for tracheal intubation with an aerosol box.Methods: This prospective, randomized, crossover simulation study was conducted at an operating room of the two hospitals (a university hospital and a tertiary teaching hospital). We recruited 37 medical personnel (36 anesthesiologists and 1 dental anesthesiologist) who were working in the fields of anesthesia and intensive care with > 2 years of dedicated anesthesia experience from five hospitals. We divided the participants into six groups to use the laryngoscope in a determined order. After the training using each laryngoscope without a box, the participants performed tracheal intubation thrice with each laryngoscope with at least two-hour intervals. The primary outcome was the intubation time. The secondary outcomes were the success rate, Cormack-Lehane grade, and subjective difficulty scale score (numeric rating scale 0–10, 0: no difficulty, 10: highest difficulty). We used the Friedman test and the Wilcoxon signed-rank test with Bonferroni adjustment. Data are shown as median [interquartile range].Results: Thirty-seven personnel (11 women and 26 men) with 12 [5–19] (median [interquartile range]) years of anesthesia and intensive care experience were enrolled. There was no significant difference in the intubation time: 30 [26–32] s for Macintosh, 29 [26–32] s for i-view, and 29 [25–31] s for C-MAC (P=0.247). The success rate was 95%–100% without significant difference (P=0.135). The i-view and C-MAC video laryngoscopes exhibited superior Cormack-Lehane grades and lower subjective difficulty scale scores than the Macintosh laryngoscope; however, there were no differences between the i-view and C-MAC video laryngoscopes.Conclusions: Rapid and highly successful tracheal intubation was possible with Macintosh laryngoscope, i-view, and C-MAC video laryngoscopes on a manikin with an aerosol box. Improved Cormack-Lehane grade and ease of procedure may support the use of video laryngoscopes.Trial registration: UMIN Clinical Trials Registry, identifier UMIN000040269.
Comparison of the TruView PCD video laryngoscope and macintosh laryngoscope for pediatric tracheal intubation by novice paramedics: a randomized crossover simulation trial