Comparison of intubation success of video laryngoscopy versus direct laryngoscopy in the difficult airway using high-fidelity simulation.
BACKGROUND
A number of devices, including video laryngoscopy, are used to aid in managing difficult airways. The goal of this study was to compare timing and success of video laryngoscopy to standard laryngoscopic intubation using a simulation mannequin in normal and difficult airway scenarios.


METHODS
Residents and attending physicians of a PGY 2-4 emergency medicine residency program participated. A single, high-fidelity simulation mannequin was used. Each participant received an in-service on the video laryngoscope (GlideScope). Three airway settings were used: standard, decreased neck mobility, and tongue edema. Participants intubated with a Macintosh blade and video laryngoscope in each scenario, and graded the best view achieved using the Cormack-Lehane classification. Outcome measures included time to view the vocal cords, time to intubation, grading of view, and intubation success or failure. Institutional Review Board approval was obtained.


RESULTS
Fifty-two participants were enrolled. Participants successfully intubated the mannequin faster using the Macintosh blade in both the normal and neck immobility settings (9.4 seconds faster, 95% CI 3.2-15.7, P = 0.004, 16.1 seconds faster, 95% CI 3.6-28.7, P = 0.01). In the tongue edema setting, however, video laryngoscopy provided a better grade view of the cords, a higher success rate of viewing the cords at time of intubation (50% vs. 12%), and a higher rate of successful intubations (83% vs. 23%). The GlideScope also significantly reduced the time needed to view the cords (89 seconds reduction, 95% CI 54.4-123.7, P < 0.0001) and intubate (131.3 seconds reduction, 95% CI 99.1-163.6, P< 0.0001) for the tongue edema setting.


CONCLUSIONS
In the most difficult airway case, tongue edema, the video laryngoscope provided an enhanced view of the cords using less time, increased intubation success, and decreased the time to intubation.
Narang
Aneesh T
AT
Department of Emergency Medicine Boston Medical Center, Boston, Massachusetts 02118, USA. annarang@bmc.org
Oldeg
Paula F
PF
Medzon
Ron
R
Mahmood
Ahmed R
AR
Spector
Jordan A
JA
Robinett
Derek A
DA
D000402:Airway Obstruction; D006801:Humans; D007396:Internship and Residency; D007442:Intubation, Intratracheal / Q000592:standards*; D007828:Laryngoscopy / Q000379:methods*; D008348:Manikins; D011214:Practice, Psychological; D011446:Prospective Studies; D013663:Teaching / Q000379:methods*; D014741:Video Recording