Thinking of increasing pressure, what are the issues.

My pressure is set to 8.0

For about the first 30 to 90 minutes of the evening my spO2 is low and then is good for the rest of the night.

I am thinking of just increasing the pressure to 10.0.

I don't have any discomfort with my nasal pillows. I actually like the sensation of them filling my lungs with air.

I thought I could do it for a few days and see what happens.

Then review the data. The risk is central apneas if I understand correctly. Currently I don't have any. My AHI index is fairly low, usually less than 1.0.

Any issues with this?

sleepy1235 wrote:My pressure is set to 8.0

For about the first 30 to 90 minutes of the evening my spO2 is low and then is good for the rest of the night.

What are you calling “low”? Are you talking about desaturation events? Please post a chart!

sleepy1235 wrote:I am thinking of just increasing the pressure to 10.0.

If you have no obstructive apneas why would you want to do that?

sleepy1235 wrote:I don't have any discomfort with my nasal pillows. I actually like the sensation of them filling my lungs with air.

I thought I could do it for a few days and see what happens.

Then review the data. The risk is central apneas if I understand correctly. Currently I don't have any. My AHI index is fairly low, usually less than 1.0.

Any issues with this?

If your SpO2 is relatively stable and running above 92% I see no reason for the change.

My way of doing things is to notice actual events in my airflow data, try lifestyle changes first, then if those fail consider a pressure change.

Besides the risk of centrals from the respiratory gain being raised by the CPAP pressure there will also be more noise and a higher chance of leaks. I would rather not go up in pressure if at all possible but if there are obstructive events and my daytime feel is bad I will consider it, after trying lifestyle changes.

I disagree with Todzo, and suggest the likelihood of provoking meaningful centrals by trying your pressure at 10 vs 8 is no big deal - quite a lot of us, if not a small majority, are at 10, and the bugaboo about centrals and high pressure is just that. If you were to raise the number a lot higher (<15) then there might be a small cause for concern, though many people - often on bipap - are also at those numbers without having induced centrals. Certainly a short trial period should not be a problem at all, especially if you try things first at 9 for a week or so, then go up to 10 if you feel the need.

It drags along at 90 to 91%.

With an air filter in the room I don't hear the machine. Even without an air filter I have never even noticed the machine noise. I fall asleep fairly quickly.

I do notice some SpO2 drops occasionally, but the S9 elite doesn't mark them as obstructive apneas.

I think an increase of 2 could be interesting to try.

Looking at this from another perspective if your goal is to change the O2 levels in your blood stream changing CPAP pressure is unlikely to affect that. Why? CPAP acts like a bit of increase in inspiration muscle tone. As if the air intake muscles were “a bit stronger” with the same brain signals applied. But the system must compensate for that always anyway. The signaling to the muscles and the efficiently of the muscles, not to mention body position and other factors of lung efficiency, are why the system uses feedback from sensors in the body to determine the changes in the drive which will compensate for the efficiency changes (and metabolic need changes) that occur constantly.

So if the gain of the system is as it should be (a bit less than one) the levels will come back to whatever “set points” the body has for the sensor blood gas levels. Changing CPAP pressure will make no difference.

If you, however, drive the system gain with the CPAP pressure above one breathing will become unstable and that is always bad!!!

I see no up side to your plan.

For about the first 30 to 90 minutes of the evening

What is the ramp setting?

How are you feeling during the day? Energy level? Daytime sleepiness?

sleepy1235 wrote:It drags along at 90 to 91%.

With an air filter in the room I don't hear the machine. Even without an air filter I have never even noticed the machine noise. I fall asleep fairly quickly.

I do notice some SpO2 drops occasionally, but the S9 elite doesn't mark them as obstructive apneas.

I think an increase of 2 could be interesting to try.

How old is your pulse oximeter and when was the last time you changed batteries and cleaned the sensor bay.

What does it read the rest of the night.

Do you have any known lung issues?

I think it is unlikely it will help or hurt, especially since you seem to have nightly data available and know how to use it?

I think before any of us can make an educated suggestion we really need to see the graphs. Not only the oximeter graphs but the CPAP graphs as well.

CG may be onto something. If your ramp is set low and long that could add to the problem. Especially with as low a pressure as you have.

My two cents:

1) We need the charts. Both CPAP and oximeter if possible. We also need to know if you are awake for most of this time or for very little of the 30-90 minutes you are talking about. And we need to know about whether you are using a ramp or not.

2) If you are actually AWAKE during most of the 30-90 minute period when the O2 levels are low, that's a problem that needs to be reported to your PCP. If you are ASLEEP during that time, I'd say that reporting the problem to the sleep doc is in order (if you have one) or the PCP (if you don't have a sleep doc) rather than self-treating. But I will admit that when all the event numbers look good, I'm more cautious about messing around with my settings than many people around here are.

3) You need to have an idea of what you want to accomplish with the pressure increase. You say that you're trying to get the O2 readings up during the first 30-90 minutes. But its not clear to me how increasing the PAP pressure will accomplish that goal if you are not having events of some sort during that time. (I don't often agree with Todzo, but in this case I think he raises a few good questions.) Are you actually have some kind of symptoms that you want addressed other than increasing the numbers being reported by the oximeter?

4) I would NOT increase the pressure by a full 2 cm in one jump. That is (to my poor suffering aerophagia plagued stomach) a huge jump. While you are currently experiencing no problems at 8cm, you may very well have problems at 10cm. (For example, I have no problems with aerophagia when my pressures are at 7/5, but I have SEVERE problems when my pressures are at 9/7, a mere 2cm increase in both IPAP and EPAP.) And, as I've pointed out to Julie more than once, just because some people, including her, are very uncomfortable breathing at low pressures does not mean everybody is. If you are determined to increase the pressure, I would suggest increasing it very slowly in 0.5 increments. And leave it at the new level several days to a week before making another increase. The reason is two-fold: First, a minimal pressure increase is less likely to trigger problems with aerophagia, leaks, or centrals. Second, I do believe that using excess pressure in the long run is uncalled for and may have some unforeseen consequences. And a slow increase in pressure would allow you to identify whether 8.5 or 9cm would do what you want it to do.

robysue wrote:

...just because some people, including her, are very uncomfortable breathing at low pressures does not mean everybody is. If you are determined to increase the pressure, I would suggest increasing it very slowly in 0.5 increments. And leave it at the new level several days to a week before making another increase. The reason is two-fold: First, a minimal pressure increase is less likely to trigger problems with aerophagia, leaks, or centrals. Second, I do believe that using excess pressure in the long run is uncalled for and may have some unforeseen consequences. And a slow increase in pressure would allow you to identify whether 8.5 or 9cm would do what you want it to do.

I agree. My pressure is fine for me... and low. If I decide for whatever reason to increase, I'd only increase in 0.5 increments.

A while back I did experiment by increasing from 6 to 8 and it felt like a hurricane and very uncomfortable. It just makes good sense to increase in small increments.

For me, less than 10 cm H2O would make me feel like suffocating and over 14 cm H2O kept blowing leaks in the mask, waking me up really grumpy. The sleep doc also saw that my AHI's and other bad stuff actually increased with higher pressure and backed the top down to 14.

The posting of graphs on this board isn't anonymous. I see that it is a URL you put in. You can't paste in a graph. So it isn't an option for me.

Special thanks to ObeoVet for the input. Very useful information to know.

sleepy1235 wrote:The posting of graphs on this board isn't anonymous.

It is if you know what you are doing.

Post the graph as a photo in your FB account using Privacy Setting "Me".

That URL will be untraceable.

(There are other ways to do it with privacy.)

Just about every response on this thread asks some sort of question. To me, these questions indicate what you should be looking for when adjusting your pressure. If you are looking at your numbers, your overall health and how you feel (during the day), there is nothing wrong with tweaking your pressure. I do it in a half a cm/h2o increments over a long period of time. I started out at a prescribed pressure of 13. After tweaking the pressure for about a year, I found my "sweet spot" at 14. Go ahead and bump up your pressure a 1/2. Document your numbers and include how you feel in the morning upon waking and how you feel during the day. Be sensitive to your health, and don't make dramatic changes. You'll soon find your "sweet spot".

Sheriff

I would post charts, but you have to use a URL and that compromises confidentiality I think.