What causes reflux?
Most of the time, when we swallow, food goes down the throat through the esophagus and into the stomach. The esophageal sphincter is a muscle at the bottom of the esophagus that relaxes so food can enter the stomach. This muscle closes to keep stomach contents from going back into the esophagus. Reflux may occur if this muscle relaxes at the wrong time or relaxes too much. The stomach makes acid to help digest the food we eat. When someone has reflux, the acid comes up along with the food. The esophagus or the airway may become irritated.
How does gastroesophageal reflux cause breathing problems?
When the stomach contents go back up the esophagus, the contents
may enter the nose, trachea (windpipe) or lungs. Aspiration occurs
when stomach contents, liquids or food enters the lungs.