Ventilatory pattern during sequential swallowing in healthy adults

Sequential swallowing, characterized by multiple swallows in rapid succession provides an efficient way to drink large quantities of liquid quickly. Our aim was to study the ventilatory pattern during sequential water swallowing (SWS) at healthy state. 31 healthy adults were studied at rest and during SWS (12/minute and 24/minute). We measured the nasal pressure using a nasal cannula and the swallows were identified by a laryngeal sound recording. The oxygen saturation (SpO2) was monitored. During SWS we analyzed the continuity of ventilation and we determined the respiratory phase before and after each swallow. We measured also the inspiratory time (TI), the expiratory time (TE), the duration of ventilatory cycle (TT=TI+TE) and the SpO2 at rest and during SWS. During SWS (12/minute), we identified swallowing apneas which occur often during expiration (type EE: 68,43% ± 25,14% of swallows). The TI decreased (1085,34 ± 172,29 msec vs 1372,54 ± 258,702 msec) and the TE increased (2524 ,73 ± 617,08 msec vs 1958,96 ± 459,87 msec) compared to rest (p