I started on CPAP a few years ago at a setting of 19. Since switching primary doctors, I have been working on improving my health, and have lost 35 pounds so far! Then the bloating started. It was quite painful, and would hurt so bad, it was waking me up at night. I told my doctor about it, and also that I had lost weight. An APAP machine was ordered for 3 weeks, and it was determined that my pressure needed to be lowered to 13, and the pressure of 19 was now filling my stomach full of air. I am doing great now!