LARYNGEAL SURGERY BY 3-DIMENSIONAL (3D) E NDOSCOPY VIA JET-LARYNGOSCOPE USING SUPERIMPOSED HIGH-FREQUENCY JET VENTILATION (SHFJV)

Surgery by 3-dimensional (3D) endoscopy is being used routinely in abd ominal surgery and, in special cases, in thoracic surgery; however, it has not been reported to be used in laryngeal surgery. Methods: We in serted a 3-D endoscope into a jet laryngoscope and studied the pressur e properties at the tip of the jet laryngoscope as well as the intrapu lmonary pressures while applying SHFJV The studies were conducted init ially using a lung simulator, and then 3-D 6 patients undergoing endos copic laryngeal surgery. Results: Due to the rather large 3-D endoscop e the diameter of the jet laryngoscope was reduced between 25.2% and 7 0.9% depending on the size of the jet laryngoscope. The measurements o n the lung simulator revealed that the reduction of the diameter of th e jet laryngoscope leads to an increase in the following parameters: e xpiratory resistance, tidal volume, and peak inspiratory pressure. The mean FiO2 was 0.74 +/- 0.1; the mean airway pressure was 19 +/- 5.3 m mHg prior to the insertion of the endoscope and 12.3 +/- 6.9 mmHg afte r the insertion. The mean PEEP values increased from 2 +/- 0.6 to 3.6 +/- 2.3 mmHg. Reduction of the working pressure resulted in regaining the initial inspiratory pressures and tidal volumes. Conclusions: In t he clinical application of 3-D endoscopy via a jet laryngoscope it was possible to achieve sufficient ventilation, inspection of the surgica l field and performance of the surgical procedure. A CO2 laser was use d without changing the ventilation regime. Although technical alterati ons would be desirable for the special application of the 3-D endoscop e to laryngeal surgery, it is presently possible to safely use the 3-D endoscope via the jet laryngoscope for phono surgery, presenting the surgeons with new possibilities in voice improving surgery of the lary nx.