| 摘要 |
A tracheotomy valve unit for use with a tracheotomy tube inserted into a patient's trachea comprises a first end for connection to the tracheotomy tube, a second end comprising a valve unit inlet, a first valve that permits airflow to the tube when the patient inhales and blocks airflow from the tube when the patient exhales thereby permitting speech, and a second valve that permits airflow from the tube back out the valve unit when the intrathoracic pressure during expiration is greater than about 12 cm of water. The second valve functions as a pressure release valve that increases tolerance and wearing comfort. In one embodiment, the second valve comprises a slit valve or an umbrella valve. |
