title: GlideScope vs. C-MAC for Awake Upright Laryngoscopy.
abstract: 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.
authors.affiliation: Department of Emergency Medicine, Allegheny Health Network, Erie, Pennsylvania.
authors.forename: Andrea Skye
authors.initials: AS
authors.lastname: Drenguis
authors.affiliation: Department of Emergency Medicine, Allegheny Health Network, Erie, Pennsylvania; Department of Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Jestin N
authors.initials: JN
authors.lastname: Carlson
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D020704:Laryngoscopes; D007828:Laryngoscopy / Q000295:instrumentation* / Q000379:methods; D008297:Male; D055100:Optical Fibers; D011187:Posture; D011446:Prospective Studies; D014741:Video Recording; D020535:Video-Assisted Surgery / Q000295:instrumentation / Q000379:methods*
keywords: C-MAC; GlideScope; airway management; awake intubation; video laryngoscopy