Aspiration

Feeding is complicated. One has to chew the food into a bolus, push it to the back of the throat and then coordinate a swallow that simultaneously sends the food down into the esophagus while covering up and protecting the airway. This process involves more than 30 nerves and approximately 50 pairs of muscles! Any delay, disruption or dyscoordination of this process can lead to food or liquid going down into the lungs. This is called aspiration.

Swallowing

There are three stages in the swallowing process. The first phase is the oral phase where chewing or moving the food bolus around the mouth occurs. The second phase is the pharyngeal phase where breathing stops, the voice box lifts up and the epiglottis closes on top of the voice box. Also during this phase the esophagus opens up and receives the food bolus. The third phase is the esophageal phase where food passes down the esophagus into the stomach.

Aspiration

Failure to direct food from the mouth down into the stomach can lead to an aspiration event. Aspiration occurs when food or liquid passes through the vocal cords and enters the airways or the lungs. An aspiration event may appear as if a child is choking or can manifest with coughing during or just following a feed. Chronic, small amounts of aspiration may not be obvious and can often be “silent”. Silent aspiration can lead to airway inflammation and a chronic cough that is unrelated to feeding.

Coughing during or after feeding or drinking does not necessarily mean your child is aspirating. The cough reflex (aka: laryngeal chemoreflex) is a reflex that occurs when liquid or food touches the larynx or vocal cords. The stimulus sends the body a signal to cough, in order to prevent food or liquid from entering the lower airway (aka: aspiration). Coughing with feeding is not normal and may be a sign that the normal process of swallow is dysfunctional. If your child is experiencing a cough during or after feeding, it may be worth a discussion with your pediatrician or a pediatric pulmonologist.