B. **Jet Venturi ventilation:**


**Figure 5.** *Tritube: (Tritube, Ventinova medical, Eindhoven, the Netherlands).*

Tracheal jet ventilation is better than supra-glottic jet ventilation [7], because tracheal jet ventilation helps the operating surgeon with less movement of the vocal cords. This is very important while performing phono-microsurgery. Also, it allows for better end-tidal CO2 monitoring. On the other hand, Jet ventilation (supra-glottic, as opposed to subglottic) is safest when used proximally. However, movement of the vocal cords due to jet air will effect on the perfection of the surgical technique.

3.Tracheal Jet ventilation using plastic catheter inside the trachea: for example: Hunsaker Mon-Jet infra-glottic ventilation catheter (**Figure 7**) or tri-lumen catheter with Twin-stream jet ventilator.
