1. Cough and Aspiration of Food and Liquids Due to Oral-Pharyngeal Dysphagia 
Carol A. Smith Hammond, PhD, Larry B. Goldstein, MD 
CHEST 
Volume 129, Issue 1, Pages 154S-168S (January 2006)
DOI: /chest.129.1_suppl.154S
Copyright © 2006 The American College of Chest Physicians Terms and Conditions

2. Figure 1
Schematic of anatomic structures and physiologic function of the normal swallow. During the oral preparatory phase, food and saliva are masticated to form a bolus. The soft palate lifts to close off the nasopharynx as the tongue slides the bolus along the hard palate. The bolus is then propelled under positive pressure into the pharynx. The duration of the pharyngeal phase is 1 to 2 s and involves a rapid sequence of events that protect the airway. The hyoid bone and larynx move upward and forward, the vocal folds move to the midline, and the epiglottis folds over the arytenoid cartilages. The tongue pushes backward and downward into the pharynx to provide positive pressure to propel the bolus. The pharyngeal walls then move inward with a progressive wave of contraction providing continuing pressure to move the bolus through the upper esophageal sphincter into the esophagus. The bolus traverses through the pyriform sinuses, which are hypopharyngeal spaces formed by the lateral pharyngeal wall and the larynx. During the esophageal phase, the upper esophageal sphincter is opened and the bolus passes into the proximal esophagus. The upper esophageal sphincter closes after passage of the bolus to prevent swallowed material from reentering the larynx. The bolus moves by a pressure wave through the esophagus.
CHEST  , 154S-168SDOI: ( /chest.129.1_suppl.154S)
Copyright © 2006 The American College of Chest Physicians Terms and Conditions

3. Figure 2
Examples of airflow records from healthy subjects (top left, 1) and stroke subjects (top right, 2, bottom left, 3, and bottom right, 4) during VC. Zero airflow is depicted as a horizontal dotted line. All phases of VC are illustrated as follows: inspiration phase, A to B; compression phase, B to C; expulsion phase rise time, C to D. Control subjects were significantly different from stroke patients as a group for all cough measures (p < 0.001). Note the increased expulsion phase rise time in aspirators (bottom left, 3, and bottom right, 4) compared to stroke patients who did not aspirate (top right, 2).
CHEST  , 154S-168SDOI: ( /chest.129.1_suppl.154S)
Copyright © 2006 The American College of Chest Physicians Terms and Conditions