Settings question

This has probably been discussed before, but I'll take a chance and ask again. I have the ResMed S9 Elite. I was using nasal pillows, but the machine setting was for a nasal mask, and I didn't notice it was on the wrong setting for a couple of days. My readings seemed normal. So, the question: what does the type of mask setting really do? I usually use the Swift LT, but when my nares get sore, I switch to the Mirage Vista. Does the incorrect setting affect the therapy? Thanks.

Mask setting only affects the reported leak numbers.
With each choice in setting the machine subtracts a predetermined vent rate before reporting leak rate.
Nasal pillows will normally have a little less vent rate so the machine might be off a wee bit in the leak number reported but it won't be much and it sure won't affect your therapy.

Vent rate for nasal pillows and a nasal only mask...aren't all that different. Full face masks typically will have a higher vent rate so if someone had the choice set for full face (and was using nasal mask or nasal pillows)..the leak might be reported as lower than it was...that would be the worst case scenario. Even then the numbers wouldn't be grossly off.

Switching back and forth between a nasal pillow mask and a nasal (cover the nose only) mask won't affect the leak numbers much and will not affect therapy at all.

Check your mask literature for the vent rates for each mask that you use at your pressure and you will see that the difference is not a huge amount.

Thanks, Pugsy. I understand now! I knew someone would be able to explain it to me!!