[Initial experiences with rigid angled optical systems as intubation aids in difficult intubation]

Referring to a classification by Cormack, difficult laryngoscopy of Grade 3 (only the epiglottis or a part of it can be seen) was simulated in 16 patients by lowering the blade of the laryngoscope, so that the epiglottis was pushed down and thus covered up the vocal cords. The object of the study was to test whether a newly developed rigid endoscope is a useful tool during intubation in cases of laryngoscopical view Grade 3. After simulation of Grade 3 as mentioned above, using a clip, an angle optic was fixed to the vertical part of the blade, so that the movement of the optic in the sagittal level was still possible. If an improvement of the laryngoscopical view was possible, the tracheal tube was inserted via the nasal route until the top of the tube could be seen in the oropharynx. The tracheal tube was inserted into the trachea, under endoscopic control. With this new method, naso-tracheal intubation under endoscopic control in all 16 patients was successful, without affecting the pharynx and the vocal cords.