What is hte minimal CPAP pressure that is safe to use?

[DannyCPAP]

I can lower the pressure to a minimum of 4, but is it safe (enough air flow) to use overnight?

[lazer]

I can lower the pressure to a minimum of 4, but is it safe (enough air flow) to use overnight?

, <removed> hehe

[BlackSpinner]

I can lower the pressure to a minimum of 4, but is it safe (enough air flow) to use overnight?

The minimum is the one that stops your apneas.

[greatunclebill]

you can probably breathe with 4, but if comfort is the real goal, don't even use the mask. you'll probably get the same amount of therapy with or without the mask at that pressure.

[chunkyfrog]

If I don't have at least 7, I feel like I'm being suffocated.
12 would stop nearly all of my apneas; but we are all different.
Why would you want to go so low? --other than to get an estimate for untreated AHI?

[jen4700]

I can lower the pressure to a minimum of 4, but is it safe (enough air flow) to use overnight?

The minimum is the one that stops your apneas.

This is true. If 4 isn't going to stop the apneas then it's not safe. Why do you ask? Maybe if we had a little more info...

[Pugsy]

4 cm pressure during the night would be safe to use from the stand point of enough air moving period.
Now whether you felt comfortable at 4 cm might be another story. If you are used to higher pressures and suddenly drop down to 4 cm then it likely will be uncomfortable because you aren't used to it and it will seem like not enough air moving. You may feel like you are suffocating but you won't be. I am used to 10 cm and a drop to 8 cm makes it seem like I am having trouble moving air. A drop to 4 cm would likely feel like I was trying to breathe through a straw with a cheese cloth filter on it. In reality I wouldn't really be in any danger but I imagine it would sure feel like I was.

I remember the titration study and 4 or 5 cm felt like a hurricane and now it feels like no air movement at all.

If someone is contemplating trying minimum pressure just to see what would happen....remember it does have therapy value and if the AHI and everything is quite low...it doesn't mean that there is no need for the machine based solely on the absence of apnea events at 4 cm pressure. It might mean that and it might mean that a person only needs say maybe 3 cm pressure to treat events. If someone does want to experiment to see...go down slowly so you can adjust. Keep an eye on the AHI and if it starts climbing a lot even prior to reaching 4 cm...you have your answer already.

[lazer]

4 cm pressure during the night would be safe to use from the stand point of enough air moving period.
Now whether you felt comfortable at 4 cm might be another story. If you are used to higher pressures and suddenly drop down to 4 cm then it likely will be uncomfortable because you aren't used to it and it will seem like not enough air moving. You may feel like you are suffocating but you won't be. I am used to 10 cm and a drop to 8 cm makes it seem like I am having trouble moving air. A drop to 4 cm would likely feel like I was trying to breathe through a straw with a cheese cloth filter on it. In reality I wouldn't really be in any danger but I imagine it would sure feel like I was.

I remember the titration study and 4 or 5 cm felt like a hurricane and now it feels like no air movement at all.

If someone is contemplating trying minimum pressure just to see what would happen....remember it does have therapy value and if the AHI and everything is quite low...it doesn't mean that there is no need for the machine based solely on the absence of apnea events at 4 cm pressure. It might mean that and it might mean that a person only needs say maybe 3 cm pressure to treat events. If someone does want to experiment to see...go down slowly so you can adjust. Keep an eye on the AHI and if it starts climbing a lot even prior to reaching 4 cm...you have your answer already.

I basically answered the same as the bolded points above in my original reply. Then when everyone came in with the "no-no's", I got chicken shit and did an "avi" to my response.... Lol...

Thanks for clearing that up and giving a much more detailed answer to the OP than I had. But that was exactly what I was trying to say in my abbreviated response.

[chunkyfrog]

YUM!
---Oh, bother!

[archangle]

4 is the specified minimum pressure for the Mirage FX nasal mask and most other masks.

You might get a little more rebreathed air, but it shouldn't be seriously harmful to you.

If 4 is too low to stop your apnea, you won't be getting effective treatment and will suffer the effects of apnea. It really shouldn't be worse than no CPAP, though.

For some reason, lots of us feel like we're being smothering at 4 cmH2O even more than we do with NO CPAP, but that would seem to be psychological.

[Pugsy]

I basically answered the same as the bolded points above in my original reply. Then when everyone came in with the "no-no's", I got chicken shit and did an "avi" to my response.... Lol...

Those other responses came from the getting adequately treated side of what 4 cm use might do. Obviously it might not do a good job.
When someone asks a question like this I figure that they already know about pressures needed to be effective (especially this OP who has been around for a long time) so I just answer the plain original question. Is it safe to use? Sure it is safe to use. Does it feel good or adequately prevent apneas? Probably not but there are people whose OSA only happens to maybe need that 4 cm of pressure. So it really isn't for me to say what would be effective in this situation. I don't remember what pressure this OP was using anyway. For all I know it could have been only 6 cm anyway.

I assume that when someone (especially cpap veteran) asks about trying the minimum that they are for some reason wondering if their sleep apnea is still there. Like maybe someone has lost a lot of weight and wondering if they are lucky enough to have the diagnosis go away. Those people I would suggest doing the reduction slowly anyway. Easier to adjust to and they might find out their answer before they get to 4 cm. If still no real events showing up at 4 cm...then time for a real sleep lab study to find out for sure before selling the machine on craigslist.