Small one-way valves can be attached to a tracheostomy tube. On inspiration, they allow air to flow in via the tube, but the valve closes in expiration, which forces air past the tube to the upper airways and enables speech.

Question: In what circumstances should a speaking valve not be used?

Answer

Speaking valves can be used to help improve the flow of gas out via the upper airways. Whilst they promote speech, they also can have additional beneficial effects on laryngeal function. The resistance to expiration can help patients to 'bear down', helping with movement and opening the bowels.

The additional resistance does add work to breathing and so carefully monitor patients when they first start using a valve. It is best to start for short periods of time.

Using a fenestrated tube will improve the laryngeal gas flow and can help in some situations. Be careful with ventilated patients and fenestrated tubes as a slight displacement can risk subcutaneous emphysema.

Be especially vigilant when a patient has a cuffed tracheostomy that is being deflated intermittently for use with a speaking valve. Everybody caring for the patient must appreciate that the cuff must never be inflated when a speaking valve is attached. Handovers and staff breaks are peak danger periods.

Fig 1 is a video showing staff carefully performing a speaking valve trial.