Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account

New Posts   Today's Posts

How to set correct cpap setting using apap data
Average AHI : 2.3
Average Pressure : 8.8 cmH2O
Average 90th Percentile Pressure : 9.5 cmH2O
Average Leak : 55.4 lpm
Average Time with Large Leak : 3.1 min

This is my latest data covering 65 days. Using this I am wondering what I should set my constant pressure Cpap if I need to use it.

I had a sleep study 16 years ago. 13cmH20 was prescribed but I couldn't take it. It was then changed to 11 and checked with a thingy on my finger at home to make sure I was getting enough oxygen . And it was ok.

It turns out my old cpap was really putting out 11.7 or 11.8 at that setting. I also always until my new equipment used to let my mask leak a little because it was way too stuffy to breathe in and out otherwise.

I wonder if I should stick with say 11 or 11.5 or alter it after seeing my apap data.

I can say 12 or below is usually where I'm at but on a couple occasions I did bump up to 14 and 15ish. I am not counting a night or two when things went beserk and jumped to 20.

So, what do you think would be a good setting for the constant pressure cpap now?

Do i need to test on my apap in cpap mode and check that data and/or can you get enough of an idea with the info I've given here?
Post Reply Post Reply

Donate to Apnea Board  
Hi. I am just at the stage of starting therapy and trialling some different CPAP devices. So I am new and keen, and doing a lot of research. I had a sleep study done and my pressure was determined by the technicians and doctor. I didn't think that you could "just change the pressure" you thought was correct. I also discovered that by trialling different machines and mask I am getting much more comfortable.
If you can try renting for a short time. I am not giving suggestions on what brands to use as I have found what suits me does not necessarily suit you.
I can see that the cost of getting the mask right, will be expensive.
Would like your thoughts.Sleep-well
Post Reply Post Reply
Lanco, fixed CPAP is normally set at the 90th percentile of pressure (amount equaled or exceeded 10% of the time). You might try a fixed pressure of 9.5-10.0 and see how it goes. If AHI remains controlled and you feel pretty good, that setting would be "by the book". If you have problems at what your machine has recorded long-term as the 90% pressure, small incremental increases to your comfort point would be in order.
Post Reply Post Reply

I see you live in Australia and that prices there are very high. I am aware of a number of people from Australia that have purchased their equipment from dealers on the US suppliers list on this site at huge savings. I would check that out.
Post Reply Post Reply
(09-15-2016, 08:40 AM)Sleeprider Wrote: (amount equaled or exceeded 10% of the time)

not sure if i know what that means.

I thought I'd heard as you said to go by the 90% to come up with a fixed pressure setting but it actually doesn't make any sense to me as I commonly slip up to 12, 13 etc so is the idea just to get it as good as you can and let it go at that?

I also know that the higher you go it can about blow you away and that the fixed pressure for exhaling can become uncomfortable.

From what I have gathered it sounds like I could get either better or worse results at fixed pressure depending on the person. Is that right?

Post Reply Post Reply

Donate to Apnea Board  
The 90th percentile pressure is the pressure that is equaled or exceeded 90% of the time; it is also the pressure that the CPAP stays at or below 90% of the time. Percentile is a common statistical term and it has more to do with frequency (time at pressure), than as a comparison to the maximum (0.9*Pmax).

When titrating for CPAP using an auto machine, the general recommendation is to use the 90th percentile pressure for constant CPAP pressure. What this means is that a pressure less than the maximum pressure is usually therapeutically sufficient and more comfortable for the user. I would expect the 90th percentile pressure to deliver comparable therapy to what the APAP delivered. Some people find fluctuating pressure to be disruptive, and those people tend to benefit from CPAP pressure. Others are sensitive to higher pressure and prefer to spend more time at a lower pressure and let the machine increase pressure only when needed. By setting a machine at the 90 percentile pressure, you will spend much more time at a higher pressure than using APAP; 90% more time. However you will not see the highest pressure the APAP would deliver 10% of the time. The trade-off is, the pressure is constant through the night and should become unnoticeable.
Post Reply Post Reply
Thank you Sleeprider. Very good answer that I can understand.
Post Reply Post Reply
Also, I might add that unless the pressure changes are bothering you there is no compelling reason to switch to CPAP. And if the pressure changes are bothering you, you might want to try a smaller range first to see it that is tolerable before switching to CPAP.

EDIT: Well, that wasn't completely true, according to my sleep doctor there are some medical conditions that could indicate that CPAP would be preferable to APAP.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Post Reply Post Reply
Thanks Frank

Actually my main objective right now is to see how I should set my other cpap should I need to use it. But at the same time see if I like it better or have better results.

I admit I have some nights that I seem to wake up half the night but don't know if that has got to do with the changing pressures or if it's something none related but either way I need to try to narrow it down I'm thinking.
Post Reply Post Reply

Donate to Apnea Board  
Also I though the changing pressure of the apap was suppossed to be good and give optimal therapy. If I change the pressures on the apap as suggested, Frank, or if I use the constant pressure cpap I'm thinking I may not get optimal therapy, but then again maybe it would help. Guess we don't know until I experiment with it some more.
Post Reply Post Reply

Possibly Related Threads...
Thread Author Replies Views Last Post
  If I use Aflex setting on resmed s9 sleepy Bruce 3 64 10 hours ago
Last Post: Walla Walla
  apap resolving central events? sheepless 2 69 Yesterday, 03:42 PM
Last Post: sheepless
  Traded OSAs for CAs during home APAP trial - What next ? Stom 36 913 07-15-2018, 06:09 PM
Last Post: Spy Car
  [Diagnosis] New to APAP DreamStation recommended settings dgranero 10 307 07-13-2018, 09:52 PM
Last Post: tedvpap
  18 mths of apap: need help optimizing settings to feel better sheepless 88 3,278 07-11-2018, 03:46 PM
Last Post: sheepless
  Thinking of buying a new APAP machine - transfer modem? Wrz77 3 202 07-10-2018, 09:19 PM
Last Post: Sleeprider
  Need advice on setting BMC LunaG11 Grumpytoo 19 932 07-07-2018, 03:08 AM
Last Post: Chast4

Forum Jump:

New Posts   Today's Posts

About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.