[Normal frequency jet ventilation using a nitrous oxide-oxygen mixture (NFJV/SoSG) for microlaryngoscopy and endolaryngeal microsurgery: performance of the Dresden apparatus system, results of experimental purposes and clinical tests and comparison with other jet technics].

Presentation of intentions and devices for normofrequency jet-ventilation using N2O/O2-mixture (NFJV/SoSG). Exclusion of Venturi principle permits application of N2O/O2 to anaesthetic ventilation. The conduction of narcosis is analogous to the usual combination anaesthesia. Further advantages of method: Efficient ventilation and oxygenation (F1O2 = 0.25...0.33); minimal need of space for ventilating system; optimal and variable working conditions for the endoscopist; small economic expense. In case of undisturbed gas backflow are hazardous peak pressures excluded. In comparison with ventilation using Carden tube or HFPPV/pneumatic valve principle the NFJV/SoSG appears at the very least equivalent; in important points (need of space at small tracheal diameters; tracheal stenosis) NFJV/SoSG is superior these methods.