Can Verbal Cues Enhance Respiratory-Swallow Coordination for Individuals Following Head and Neck Cancer?

Atypical respiratory-swallow coordination is associated with increased aspiration risk and swallow inefficiency. While verbal cueing has been shown to influence respiratory-swallow coordination in people with Parkinson's disease, its effect in individuals following head and neck cancer remains unclear. This study aimed to explore the effect of verbal cuing on respiratory-swallow coordination in this population. A prospective, with-in subjects' design was employed. Respiratory Inductance Plethysmography, nasal airflow and submental electromyograms were used to capture respiratory-swallow patterning, lung volume at swallow initiation (LVSI) and respiratory pause duration. Participants were verbally cued to swallow at four different points within tidal breathing: high inhalation, low inhalation, high exhalation, low exhalation. Non-cued swallow trials served as a control condition. Eighteen participants contributed a total of 360 analysable swallow trials. A significant increase was observed in optimal phasing (exhale-swallow-exhale) in the high inhalation and high exhalation cued conditions, compared to the non-cued condition OR [95% CI] = 4.74 [1.86, 12.09]; OR [95% CI] = 2.55 [1.11, 5.86] respectively. Verbal cueing significantly increased LVSI at low inhalation relative to non-cued swallows by 19%. In contrast, verbal cues at high and low exhalation significantly decreased LVSI, with mean decreases of 28% and 32%, respectively. This study shows that verbal cueing influences respiratory-coordination in individuals with head and neck cancer and suggests cuing at high inhalation is more likely to elicit optimal respiratory-swallow coordination (exhale-swallow-exhale pattern initiated at mid tidal lung volumes), highlighting the potential for introducing targeted cueing strategies to enhance respiratory-swallow coordination.