I had my Sleep Study February 2008. It was done the old fashion way, in a sleep study building. It was scheduled for 2 nights. Both nights they would wire you up with sensors on your legs, stomach, chest, face, ears, neck, fingers, arms. Then they would give you a sleeping pill. It felt like you were wired for sound.

The first night they would take readings throughout the night. The second night they would put the wires back on and add wearing a Full Face Mask hooked up to a machine. My study was only 1 night. After I fell asleep they woke me up within 2 hours and put the mask on me. My apnea was so bad, I would stop breathing 40 to 45+ times in that hour. The next day I had my BiPAP Machine. I can't use a CPAP.
CPAP: One continues pressure during inhalation and exhalation.
BiPAP: Two distinct pressure levels. Higher for inhalation and Lower for exhalation that adjusts automatically breath by breath.
Before wearing the BiPAP the upper portion of my heart was enlarged. After about 1 or 2 years of the BiPAP my heart returned to normal.
Sleep Studies are very easy to do now-a-days. They give you a monitor and a few wires and sensors to hook up and you sleep in your own bed.
The first year or two I tried many masks. It was frustrating at first, but when I found the right mask it felt good. I've worn the Resmed Full Face Quattro for about 16 years now. My BiPAP Machine is the Resmed Aircurve 10 Auto. BiPAP Pressures are
17 cm H2O /
12 cm H2O.
I sleep like a baby using the BiPAP.

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