Swallowing

Swallowing (Deglutition)
1. Act of clearing solids and liquids into the Gastrointestinal Tract via the pharynx and Esophagus

Swallowing is complicated by food and drink sharing a common entry with air for breathing
1. When disordered, aspiration food and liquid into airway may occur
Swallowing requires complex coordination of voluntary and involuntary Muscle Contractions
1. Oropharyngeal Stages
  1. Food bolus creation
    1. Food is chewed and mixed with Saliva until necessary consistency
  2. Food moves into posterior pharynx
    1. Food is propelled forward by Tongue
  3. Airway protection
    1. Larynx rises and glottis closes during Swallowing
    2. Epiglottis falls over the Larynx, directing food posteriorly into the Esophagus
    3. Gag Reflex may induce Vomiting when stimulating the uvula and other posterior pharynx
    4. Cough expels aspirated matter that has bypassed other protective measures
2. Esophageal Stages
  1. Esophageal entry
    1. Food bolus passes into the Esophagus via the upper esophageal sphincter
  2. Esophageal transit
    1. Food bolus is propelled forward by esophageal peristalsis
  3. Stomach entry
    1. Food bolus passes through the lower esophageal sphincter into the Stomach