Influence of the cuff pressure on the swallowing reflex in tracheostomized intensive care unit patients.

Background: Because recovery of an efficient swallowing reflex is a determining factor for the recovery of airway protective reflexes, we have studied the influence of the tracheostomy tube cuff pressure (CP) on the swallowing reflex in tracheotomized patients.

Methods: Twelve conscious adult intensive care unit (ICU) patients who had been weaned from mechanical ventilation were studied. Simultaneous EMG of the submental muscles with measurement of peak activity (EMGp) and amplitude of laryngeal acceleration (ALA) were performed during reflex swallows elicited by pharyngeal injection of distilled water boluses during end expiration. After cuff deflation, characteristics of the swallowing reflex (latency time: LaT, EMGp, and ALA) were measured at CPs of 5, 10, 15, 20, 25, 30, 40, 50, and 60 cm H(2)O.

Results: LaT and CP were linearly related (P<0.01). CP was inversely correlated (P<0.01) to both ALA and EMGp.

Conclusions: We demonstrated that LaT, EMGp, and ALA of the swallowing reflex were influenced by tracheostomy tube CP. The swallowing reflex was progressively more difficult to elicit with increasing CP and when activated, the resulting motor swallowing activity and efficiency at elevating the larynx were depressed.