Purpose: This study examined the relationship between swallowing and lung volume initiation in healthy adults during single swallows of boluses differing in volume and consistency. Differences in lung volume according to respiratory phase surrounding the swallow were also assessed.
Method: Nine men and 11 women between the ages of 19 and 28 years served as study participants. Lung volume and respiratory phase data was recorded as each participant completed 5 trials each of 10mL and 20mL water boluses by cup, and thin and thick paste boluses by spoon, presented in randomized order.
Results: Significant differences in lung volume at swallow initiation were found based on bolus consistency, but not on bolus volume. No differences were found for lung volume initiation based on the respiratory phase surrounding the swallow, or for the respiratory pattern based on bolus volume or consistency.
Conclusion: Findings of this study extend the existing knowledge base regarding the interaction of the swallow and respiratory systems by identifying targeted lung volumes at swallow initiation. In addition to other swallow-related biomechanical events and respiratory phase relationships surrounding a swallow, the lung volume at swallow initiation may be an important consideration when investigating swallow physiology and physiopathy.