GlideScope vs. C-MAC for Awake Upright Laryngoscopy.

BACKGROUND: Combining video laryngoscopy with awake upright intubation may provide an alternative modality of endotracheal intubation (ETI) that avoids pitfalls associated with traditional ETI.

OBJECTIVE: We compared laryngoscopic views and time intervals between the GlideScope (GVL) and C-MAC video laryngoscopes using a face-to-face technique in awake, upright volunteers.

METHODS: We performed a prospective, randomized, crossover study performing awake upright laryngoscopy on healthy volunteers. Under local anesthesia, participants had awake upright laryngoscopy performed by a resident and attending physician, both operating GVL and C-MAC in random order. We recorded times to first view of the glottis and best view of the glottis, percentage of glottic opening (POGO) score, Cormack-Lehane grade, and number of attempts needed to visualize the glottis.

RESULTS: We enrolled 26 subjects, 10 male and 16 female (mean age of 31.9 years). GVL had shorter time to first view of the glottis than the CMAC (median 7 s; interquartile range [IQR]: 6.5-18 s vs. 9 s; IQR: 8-13; p = 0.005). However, time to best view of the glottis was similar between devices (GVL 10.25 s; IQR: 8.5-15 s; CMAC 13 s; IQR: 10-16 s; p = 0.238). GVL had higher POGO median scores (61.25; IQR: 45.5-87.5) compared to C-MAC (5; IQR: 2.5-20.5) (p < 0.001) and improved Cormack-Lehane views (median 1.5 views; IQR: 1-2 views) compared to C-MAC (median 2 views; IQR: 2-3 views; p = 0.001). Number of attempts were similar across devices (median 1; IQR, 1-1.5) for both GVL and C-MAC (p = 0.764).

CONCLUSIONS: GlideScope provides superior views to C-MAC in awake upright laryngoscopy in healthy volunteers.