What causes dysphagia?
Swallowing involves three stages.
These three stages are controlled by nerves that connect the digestive tract to your child's brain.
Oral Preparation Stage-- Food is chewed and moistened by saliva. The tongue pushes food and liquids to the back of the mouth towards the throat. (This phase is voluntary: we have control over chewing and beginning to swallow.)
Pharyngeal Stage-- Food enters the pharynx (throat). A flap called the epiglottis closes off the passage to the windpipe so food cannot get into the lungs. The muscles in the throat relax. Food and liquid are quickly passed down the pharynx (throat) into the esophagus. The epiglottis opens again so we can breathe. (This phase starts under voluntary control, but then becomes an involuntary phase that we cannot consciously control.)
- Esophageal Stage-- Liquids fall through the esophagus into the stomach by gravity. Muscles in the esophagus push food toward the stomach in wave-like movements known as peristalsis. A muscular band between the end of the esophagus and the upper portion of the esophagus (known as the lower esophageal sphincter) relaxes in response to swallowing, allowing food and liquids to enter the stomach. (The events in this phase are involuntary.)
Swallowing disorders occur when one or more of these stages fail to take place properly.
Children's health problems that can affect swallowing include:
- cleft lip or cleft palate
- dental problems (teeth that do not meet properly, such as with an overbite)
- large tongue
- diseases that affect the nerves and muscles, such as a stroke, tumor, nerve injury, brain injury, or muscular dystrophy, and can cause paralysis or poor function of the tongue or the muscles in the throat and esophagus
- large tonsils
- tumors or masses in the throat
- problems with the prenatal development of the bones of the skull and the structures in the mouth and throat (known as craniofacial anomalies)
- prenatal malformations of the digestive tract, such as esophageal atresia or tracheoesophageal fistula
- oral sensitivity that can occur in very ill children who have been on a ventilator for a prolonged period of time
- irritation of the vocal cords after being on a ventilator for long periods of time (as may occur with premature babies or very ill children)
- paralysis of the vocal cords
- having a tracheostomy (artificial opening in the throat for breathing)
- irritation or scarring of the esophagus or vocal cords by acid in gastroesophageal reflux disease (GERD)
- compression of the esophagus by other body parts, such as the heart, thyroid gland, blood vessels, or lymph nodes
- foreign bodies in the esophagus, such as a swallowed coin
- developmental delays
Why is dysphagia a concern?
Dysphagia can result in aspiration which occurs when food or liquids go into the windpipe and lungs. Aspiration of food and liquids may cause pneumonia and/or other serious lung conditions.