One-way "Speaking" valves are one-way valves that can be attached either directly onto a tracheostomy tube or inserted as part of the breathing circuit between the patient’s tracheostomy and the ventilator. They are sometimes called "One-way speech and swallow valves" or by the trade name of the commonest manufacturer, "Passy Muir" (valves). See www.passy-muir.com

These valves are ‘open’ during inspiration (when the patient breathes in, or a ventilator-supported breath is delivered) but ‘closed’ during expiration (when the patient breathes out, or the ventilator cycles into expiration). There MUST be a way for gas to escape in expiration as there will ne no gas flow via the tracheostomy tube. This means adequate room for gas to flow past the tube in the trachea and out via the upper airways. An uncuffed or cuff-deflated tracheostomy tube is therefore required.

Speaking valves should NEVER be used with the cuff inflated as this can lead to asphyxiation, respiratory arrest and death. One-way valves should also never be used with tubes with foam cuffs. Foam cuffs are designed to expand within the airway and change shape over the breathing cycle. That means that they are difficult to deflate fully. Any obstruction to the flow of expired gas around the tracheostomy tube can cause significant problems for the patient.

The airway must also be patent (clear). If there are any doubts about the patency of the airway, it must be checked - usually by a competent ENT/ORL/Head & Neck surgeon, Speech & Language Therapist (Pathologist) or a suitably trained healthcare practitioner. This will usually lead to an airway endoscopy (or FEES) where the upper airway is visualised with a small camera, usually inserted via the nose. (You can find out more about FEES here). 

These one-way valves add to the work of breathing and so they usually need to be trialled for short periods of time, building up to longer periods. Each patient is different. If the patient is still needing help from a ventilator, you need to be especially careful as the tracheostomy tube may have a cuff that is usually inflated for periods of ventilator support on respiratory rest, but deflated for periods of one-way valve use. You can find out more about using one-way valves with ventilators here

Used correctly, one-way valves can provide significant early benefits to patients as they begin the journey of laryngeal rehabilitation after tracheostomy, and continue to provide benefits during recovery and even long-term use.

If you follow the basic principles of safe use, speaking valves can be a valuable tool to help patients communicate more effectively, vocalise, clear secretions, cough, improve breathing muscle strength and improve the function of the larynx and swallowing.

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