• Marshal B Kaplan, Carin A Hagberg, Denham S Ward, Ansgar Brambrink, Ashwani K Chhibber, Thomas Heidegger, Leonardo Lozada, Andranik Ovassapian, David Parsons, James Ramsay, Wolfram Wilhelm, Bernhard Zwissler, Haus J Gerig, Christian Hofstetter, Suzanne Karan, Nevin Kreisler, Robert M Pousman, Andreas Thierbach, Marc Wrobel, and George Berci.
• Department of Anesthesiology, UCLA and Cedars-Sinai Medical Center, Los Angeles, CA 90095, USA, and Department of Anesthesiology, Cantonal Hospital, St Gallen, Switzerland.
• J Clin Anesth. 2006 Aug 1;18(5):357-62.

ObjectiveTo compare the direct and indirect (video monitor) views of the glottic opening using a new Macintosh blade that is modified to provide a video image of airway structures during laryngoscopy.DesignProspective multicenter trial.Setting11 university-affiliated hospitals.Patients867 adults undergoing elective surgery requiring general anesthesia and tracheal intubation.InterventionsPatients received general anesthesia and were paralyzed. Direct laryngoscopy was supervised by one of the investigators at each institution. The best possible view was obtained with a Macintosh video laryngoscope during direct vision using standard techniques such as external laryngeal manipulation and backward, upward, and rightward pressure, if necessary. The laryngoscopist then looked at the video monitor and performed any necessary maneuvers to obtain the best view on the video monitor. Thus, 2 assessments were made during the same laryngoscopy (direct naked-eye view vs video monitor view). Tracheal intubation was then performed using the monitor view. Glottic views were rated according to the Cormack-Lehane scoring system, as modified by Yentis and Lee. A questionnaire was completed for each patient.Measurements And Main ResultsData from 865 patients were suitable for analysis. Visualization was considered easy (Cormack-Lehane score<3) in 737 patients and difficult (Cormack-Lehane score=3 or 4) in 21 for both direct and video-assisted views. In 7 patients, the view was considered easy during direct visualization yet difficult on the video monitor view. On the other hand, the view was considered difficult in 100 patients during direct visualization yet easy on the video monitor view (P<0.001).ConclusionsVideo-assisted laryngoscopy provides an improved view of the larynx, as compared with direct visualization. This technique may be useful for cases of difficult intubation and reintubation as well as for teaching laryngoscopy and intubation.

17 keywords...

hide…