Efficiency of the King Vision Video Laryngoscope

Endotracheal intubation attempt is defined as entrance of the endotracheal tube into the patient's mouth. Any major change in the alignment of the laryngoscope is defined as another intubation attempt. Successful endotracheal intubation is defined as the endotracheal cuff passing through the patient's vocal cords. Intubation success rate is defined as: 1 / [the number of attempts].

Successful endotracheal intubation is defined as the endotracheal cuff passing the patient's vocal cords. Time to intubation with each laryngoscope is recorded.

Glottic view time (as defined when the laryngoscopist declared the best Cormack-Lehane score) with each laryngoscope is recorded.

Cormack-Lehane score is obtained by directly assessing the distance between the base of the tongue and the roof of the mouth to predict how difficult an intubation will be.

It consists of 4 grades:

• full view of glottis (difficult intubation unlikely)
• partial view of glottis (~5% risk of difficult intubation)
• partial view of epiglottis, none of glottis seen (~90% risk of difficult intubation)
• neither glottis nor epiglottis seen (difficult intubation very likely)

Best Cormack-Lehane score (as declared by the laryngoscopist) obtained with both laryngoscopes is recorded.

Cormack-Lehane score is graded according to the following criteria (1 is best, and 4 is worst):

• full view of glottis (difficult intubation unlikely)
• partial view of glottis (~5% risk of difficult intubation)
• partial view of epiglottis, none of glottis seen (~90% risk of difficult intubation)
• neither glottis nor epiglottis seen (difficult intubation very likely)

Any complication related to the laryngoscopy and intubation, such as cut, bleeding, damage to the teeth, laryngospasm, bronchospasm, desaturation below 90%, is recorded.