Subjective and objective evaluation of swallowing in lateral decubitus positions examined in healthy volunteers.

Background: Dysphagia can result from shock, trauma, aging, head and neck neoplasms, and some cerebrovascular diseases or neuromotor degenerative disorders. Swallowing rehabilitation therapy combined with postural control of the neck, head, and body can be effective for patients with dysphagia. Though the lateral decubitus posture has been a favorable option for swallowing rehabilitation therapy, available clinical data pertaining to it are scarce.

Methods: Twenty-seven healthy volunteers were enrolled in this study. The subjects underwent a repetitive saliva swallowing test, food swallowing test, and water swallowing test. The trials were performed in four different positions: upright sitting position, lateral decubitus position with the head raised to 60°, lateral decubitus position with the head raised to 30°, and complete lateral decubitus position. After each trial, the subjects were asked to declare the swallowing difficulty utilizing a visual analogue scale. Swallowing time and swallowing sound level were recorded simultaneously, as objective evaluation in each trial. We analyzed the visual analogue scale scores, swallowing time, and swallowing sound levels for all the four positions.

Results: The results of the visual analogue scale of the water swallowing test in the sitting position were significantly lower than those of the complete lateral decubitus position (p < 0.01). However, statistical significance was not detected in swallowing time or the swallowing sound level among the four different positions. Although subjective discomfort in swallowing was identified, difficulty of swallowing was not objectively evident in the trials, irrespective of the position.

Conclusions: A complete lateral decubitus position can be an effective and safe position in swallowing.