Living at altitude & a manometer

[aquanaut20]

I think the bigger issue would be the supplemental O2,  Checking with an SPO2 device would be beneficial..

....  Philip

Or, maybe I have read too many posts tonight !!!

[PaytonA]

I think the reason is because of the way CPAP machines measure flow rate. They pass air first through one pressure sensor and then a second pressure sensor. The drop in pressure between the two sensors can tell you how fast the air is moving, but that determination is a function of the air density. The air in Denver is less dense than the air in Houston, so this has to be compensated for if the machine is to be able to accurately determine flow rates. Knowing the flow rate is necessary because the machine needs to know how fast to spin the impeller to maintain the pressure. This the real engineering feat of the CPAP machine: it maintains the same pressure regardless of how fast the patient is inhaling (or exhaling).

You do not need flow rate to determine the speed the impeller needs to run. All of the machines have pressure gages. You spin the impeller up until it achieves the back pressure that is desired and there you have it. May not be real scientific but works well and is very accurate as long as the pressure gage is accurate.

Best Regards

PaytonA