11-17-2019, 08:18 AM
(This post was last modified: 11-17-2019, 08:19 AM by slowriter.)
xPAP setting changes at high altitudes (above 8000 feet)?
There's a lot of threads here on altitude, but I didn't find one with a straight answer to this to simple question:
I often travel in the Andes, and am frequently sleeping at above 10,000 feet; sometimes as high as 13,000.
Is there any need for setting changes (say min EPAP) at these altitudes?
If there is, is there a standard formula (as in, 1 cm increase of pressure/x feet above y)?
RE: xPAP setting changes at high altitudes (above 8000 feet)?
Your machine adapts up to 8000 feet and above that there is really no guidance. I have used mine at much higher altitudes as well, but nothing approaching elevations in Peru. I don't need to change settings at altitude, but some people have higher CA at altitude due to higher respiration rate. If that happens, a combination of reducing PS and minimum pressure is the obvious adjustment. I think being skilled at self-titration is a valuable skill if you significantly change altitude.
RE: xPAP setting changes at high altitudes (above 8000 feet)?
It sounds like you're saying there's probably no reason to change settings upfront, and one would only do that if CAs emerge?
I usually take acetazolamide when I ascend, to help with acclimatization. I presume that also may help mitigate CAs.
In any case, thanks; I think I understand how to approach it.
RE: xPAP setting changes at high altitudes (above 8000 feet)?
Yes. As you know the machine relies on differential pressure to maintain a patent airway. Absolute pressure drops with altitude, but differential pressure should remain constant. While these medical devices are only tested in a range of altitude where most people live, we seem to see a lot more individuals from higher altitudes (Colorado ski areas) experience more CA events, especially when titrated at lower altitude. This is similar to treatment emergent CA we commonly see on the forum. The prevailing theory is that the respiration rate, and sometimes tidal volume rises with significant altitude change. This has the effect of reducing CO2 balance, decreasing RR drive and increasing incidence of benign CA. The response is the same as anyplace else, to lower pressure and pressure support to counter the events. In your case with the Vauto, you might also increase trigger sensitivity.