Why is my stomach filling with air?

Question

I have Obstructive Sleep Apnea, and I have to sleep with a Bi-PAP machine. It doesn't happen all the time, but on occasion I wake up belching alot with a stomach full of air.

Answer 1

You are swallowing the air as well as breathing it. I'm guessing you have a full face mask? Try sleeping with you mouth shut - although it is hard if you are used to breathing through your mouth.

Answer 2

Air is going into your gastrointestinal tract (esophagus and stomach) instead of via your trachea to your lungs.