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

Surgery by three-dimensional (3D) endoscopy is being used routinely in abdominal surgery and, in special cases, in thoracic surgery; however , it has not been reported as being used in microlaryngeal surgery. Me thods. We inserted a 3-D endoscope into a jet laryngoscope and studied the pressure properties at the tip of the laryngoscope as well as int rapulmonary pressures while applying superimposed high-frequency jet v entilation. The studies were conducted initially using a lung simulato r, and then in seven patients undergoing microlaryngeal surgery. Resul ts. Due to the rather large 3-D endoscope, the diameter of the jet lar yngoscope was reduced by between 25.2% and 70.9%, depending on its siz e. The measurements on the lung simulator revealed that reduction of l aryngoscope diameter leads to an increase in the following parameters: expiratory resistance, tidal volume, and peak inspiratory pressure. T he mean FiO(2) was 0.74+/-0.1; the mean paO(2) was 169.2+/-80.4 mmHg; and the mean paCO(2) was 30.9+/-2.4 mmHg. The mean airway pressure was 19+/-5.3 mmHg prior to insertion of the endoscope and 12.3+/-6.9 mmHg The mean positive end-expiratory pressure values increased from 2+/-0 .6 to 3.6+/-2.3 mmHg. Reduction of the working pressure resulted in re storation of the initial inspiratory pressures and tidal volumes. Conc lusions. In the clinical application of 3-D endoscopy via a jet laryng oscope, it was possible to achieve sufficient ventilation, inspection of the surgical field, and performance of the surgical procedure. A CO 2 laser was used without changing the ventilation regime. Although tec hnical alterations would be desirable for its application to microlary ngeal surgery, it is presently possible to safely use the 3-D endoscop e via the jet laryngoscope for microlaryngeal surgery, presenting the surgeon with new possibilities in voice-improving microsurgery of the larynx.