Efficiency of the King Vision Video Laryngoscope

Comparison of King Vision Video Laryngoscope and Macintosh Laryngoscope in Terms of First Pass Intubation Success Rate, Intubation Time, Glottic View Time, and Complications Related to Laryngoscopy

The investigators studied the efficiency of Macintosh laryngoscope and the King Vision video laryngoscope in adult patients scheduled for general anesthesia. Best Cormack-Lehane score obtained, glottic view time, intubation time, time to ventilation, correlation between the Mallampati classification and the Cormack-Lehane grades, and complications related to laryngoscopy and intubation has been investigated.

Securing the airway is essential in general anesthesia. Anesthetic problems related to airway management constitute 17% of closed claims, difficult intubation being the most common one with an occurrence rate of 5%. Problems like delayed intubation, misplaced tracheal tube, or airway trauma are frequently seen in outpatient settings and end up with either death or hypoxic brain damage. Therefore, preoperative visit should include detailed assessment of the airways according to clues of difficult intubation.Several studies compared the King Vision video laryngoscope with other laryngoscopes in manikins simulating difficult airway scenarios, and reported better glottic views. The investigators aimed to study the correlation between the Mallampati classification and the glottic views (Cormack-Lehane grade) obtained with Macintosh laryngoscopy, and the King Vision video laryngoscopy in adult patients scheduled for general anesthesia. Secondary outcomes will be successful intubation rate, time to obtain the best view, time to successful intubation, and complications related to laryngoscopy will be compared.

Patients scheduled for general anesthesia during the period from January 2014 to June 2014. Each patient has been intubated with a Macintosh laryngoscope.

Patients scheduled for general anesthesia during the period from January 2014 to June 2014. Each patient has been intubated with a King Vision video laryngoscope.

Using a Macintosh laryngoscope, time to glottic view, best Cormack-Lehane grade, time to intubation, time to first ventilation has been recorded.

Using a King Vision video laryngoscope, time to glottic view, best Cormack-Lehane grade, time to intubation, time to first ventilation has been recorded.

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 diffcult 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.

Inclusion Criteria: scheduled for general anesthesia age higher than 18 years age lower than 60 years Exclusion Criteria: emergency surgery mouth opening less than 2 cm American Society of Anesthesiologists (ASA) score higher than 2 oropharyngeal anomaly glottic or supraglottic mass history of surgery due to oropharyngeal anomaly, glottic or supraglottic mass

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