Purpose: Expiratory flow towards the upper airway after swallowing serves to expel liquid or food particles misdirected towards the trachea during swallowing. However, expiration may not occur consistently after swallowing in tracheostomised patients with an open tracheostomy tube. We investigated the effect of a speaking valve (SV) on breathing-swallowing interactions and on the volume expelled through the upper airway after swallowing.
Methods: Eight tracheostomised neuromuscular patients who were able to breathe spontaneously were studied with and without an SV. Breathing-swallowing interactions were investigated by chin electromyography, cervical piezoelectric sensor, and nasal and tracheal flow recording. Three water-bolus sizes (5, 10, and 15 mL) were tested in random order.
Results: Swallowing characteristics and breathing-swallowing synchronisation were not influenced by SV use. However, expiratory flow towards the upper airway after swallowing was negligible without the SV and was restored by adding the SV.
Conclusion: In tracheostomised patients, protective expiration towards the upper airway after swallowing is restored by the use of an SV.