摘要 |
This invention relates to a cannula for tracheal intubation, inserted through the hole made in the trachea of the patient. The cannula is fitted at the top with a mechanically operated valve which remains open during normal breathing but which can close and consequently interrupt the flow of air to the outside when the patient, in order to direct the air towards the vocal cords, breathes out with greater force, sufficient to overcome the resistance of the spring within the valve. |