Diagnostic cues: What is more important??

Perhaps a stupid question but here goes anyway.

What is the more important number to note....

Time (min) speant at pressure (over nights sleep)

or

90% pressure with Auto CPAP?

I've had a good look over a few weeks of data and it appears that the largest amount of time spent at a certain pressure is the pressure that has the lowest number of AHI (AI and HI). This is in most situations? Now is this just math or is it a theraputic marker that we can use to adjust therapy?

Additionally....if one was to choose straight CPAP would you choose the pressure that you spend most time at and as explained from my data the pressure that the least amount of AHI ot the highest pressure you know to block all events.

I know that higher pressures (around the 13cmH2O mark) bring on central apnoeas for me

What are people's thoughts

zoolander wrote:Perhaps a stupid question but here goes anyway.

What is the more important number to note....

Time (min) speant at pressure (over nights sleep)

or

90% pressure with Auto CPAP?

90% pressure with Auto CPAP

I've had a good look over a few weeks of data and it appears that the largest amount of time spent at a certain pressure is the pressure that has the lowest number of AHI (AI and HI). This is in most situations? Now is this just math or is it a theraputic marker that we can use to adjust therapy

Its a combination of math and how the auto's algorithm works. All autos are aimed to let you spend as much time as possible at lower pressure, and to raise the pressure (preferably) pre-emptively based on anlysis of you breathing to avoid apneas. By accepting a "most time spent without apneas" as your target pressure you're sure to chose a pressure which is by definition too low to avoid all events.

Additionally....if one was to choose straight CPAP would you choose the pressure that you spend most time at and as explained from my data the pressure that the least amount of AHI ot the highest pressure you know to block all events.

I would chose the 90% recommendation, because that means that you are assured of being without apneas for 90% of the time. Resmed, by the way, thinks the number should be 95% of the time.

I know that higher pressures (around the 13cmH2O mark) bring on central apnoeas for me

This happens to me too, so what I do is have the bottom of the range slightly less than the recommended (it gets recommended every now and then, but not often) and the top of the range slightly more. My range is all of 1.5 to 2 cms/h2o wide...

O.