Delayed initiation of the pharyngeal swallow: normal variability in adult swallows.

PURPOSE: The purpose of this investigation was to determine bolus head timing and location relations with the onset of hyoid movement at the initiation of the pharyngeal swallow and at the onset of swallow-related apnea. METHOD: Bolus head timing and location and the timing of swallow-related apnea were recorded from frame-by-frame analyses of 5-ml single liquid swallows using dual-modality videofluoroscopy and nasal airflow recordings in 82 consecutive, healthy volunteers. The presence, depth, and response to airway entry were also recorded and related to the bolus head location and the onset of hyoid movement. RESULTS: The majority of participants-80% on at least 1 trial-produced the onset of hyoid movement at pharyngeal swallow initiation after the bolus head passed the posterior angle of the mandible. There was a trend in older participants for later onset of hyoid movement and onset of apnea relative to bolus head arrival at the posterior angle of the mandible. CONCLUSION: Although entry of the bolus head into the pharynx prior to hyoid movement may result in a threat to the laryngeal airway, these data demonstrate that a "delay" by itself cannot be assumed to indicate a disordered swallow without coexisting impairments of swallowing physiology.

Coordination of swallowing and respiration in normal sequential cup swallows.

OBJECTIVES: To establish normative data on laryngeal vestibular closure patterns and respiratory phase patterns during sequential cup swallows in healthy adults. STUDY DESIGN: Cross-sectional study. METHODS: Combined videofluoroscopic and respiratory phase recordings were analyzed in 70 healthy adults during 50 mL sequential liquid cup swallows. The following dependent variables were measured offline from the digitized recordings: 1) number of swallows, 2) number of ingestion cycles (IC) (period of sustained apnea including 1 or more swallows), 3) opening of the laryngeal vestibule after each swallow, and 4) respiratory phase surrounding each IC. Patients were grouped according to the position of the larynx after each swallow. RESULTS: The mean number of swallows was 4.35, and the mean number of ICs was 3.28. Laryngeal vestibular opening after swallows was categorized into three groups: Always Open = 67.1%, Mixed (Open and Closed) = 31.4%, Always Closed = 1.4%. Statistical differences were not found in laryngeal opening pattern by age or sex, but the Always Open group had fewer swallows (4.02 vs. 5.23, P = .008) and a greater number of ICs (3.62 vs. 2.41, P = .001) than the Mixed Group. Respiratory phase after IC was expiration in 79% and inspiration in 21%. CONCLUSIONS: Normal patterns of laryngeal vestibular closure and respiratory phase coordination during sequential swallowing have been described for the first time. The high occurrence of inspiration and laryngeal vestibular opening that surrounds sequential liquid cup swallows when compared with previous findings in single, discrete swallows may place patients with swallowing disorders at greater risk during this task.

Breathing and swallowing dynamics across the adult lifespan.

BACKGROUND: Aberrations in the physiologic components of normal oropharyngeal swallowing have been linked to aspiration events and to predisposition to aspiration pneumonia, a common, deadly disease in elderly persons. Studies have demonstrated a temporal, physiologic link between breathing and the principal physiologic swallowing components involved in airway protection during swallowing. We developed a normative model of integrated breathing and swallowing patterns using concomitant videofluoroscopic images and nasal respiratory airflow recordings. OBJECTIVES: To establish normative temporal and respiratory-phase pattern relationships between breathing and swallowing in adult human beings across the aging continuum; to relate any alterations in these patterns to swallowing abnormality, an aspiration event during swallowing, and predisposition to aspiration pneumonia; and to develop clinically practical evaluation methods for identifying breathing and swallowing discoordination. SETTING: Fluoroscopy suite in an acute care hospital. PARTICIPANTS: Eighty-two healthy adult volunteers gave informed consent. All eligible healthy volunteers were welcome and were screened for age, race, and sex for equal distribution of each. INTERVENTION: Respiratory-phase patterns and the onset and duration of 11 predetermined swallowing events and associated respiratory activities were studied. All participants' single-liquid barium swallow examinations were studied with simultaneous videofluoroscopy and respiratory recordings. MAIN OUTCOME MEASURES: Onset of each of the 11 predetermined breathing and swallowing events was digitally recorded and analyzed. The phases of breathing before and after swallowing were identified. The presence, depth, and response to airway penetration were recorded and related to respiratory pattern. RESULTS: Four respiratory-phase patterns were identified that changed with advanced age. The correlation analyses of the temporal breathing and swallowing events revealed a normal pattern of 4 clearly distinguishable functional units. Differences in apnea duration and apnea offset occurred with advanced age. CONCLUSION: This research provides evidence for clearly distinguishable patterns and functional groupings of breathing and swallowing events, a necessary first step toward determining whether abnormal breathing and swallowing patterns in patients with dysphagia are associated with health outcome.

Temporal coordination of pharyngeal and laryngeal dynamics with breathing during swallowing: single liquid swallows.

The critical integration of timing and patterning between respiratory and swallowing events was studied with simultaneous videofluoroscopic and respiratory recording during single liquid swallows. Respiratory phase patterns and the onsets and durations of 12 predetermined swallowing events and associated respiratory activities were studied. Results showed four highly repeatable, temporally oriented sequences (clusters) of swallowing and related respiratory events. Two respiratory phase patterns were identified without statistically significant differences in frequency of occurrence between age, gender, or race. These findings will aid in the identification of normal and abnormal patterns of breathing and swallowing in patients with dysphagia.