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.
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.
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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