[Pressure] Data Interpretation

[Sleeprider]

Remember that your "high" pressure is relatively low, especially since the exhale pressure drops by 3-cm. In post #15 http://www.apneaboard.com/forums/Thread-...#pid433579 I thought your minimum pressure would end up being about 9.0 cm. That is actually 9.0/6.0 (inhale/exhale), and looking at the mask pressure chart up close will show you how little time you actually spend at the peak set pressure. You are doing the right thing, and progressing through the pressure to find what works best for you.

[Gideon]

I am not saying you are not having issues with pressure. Many confuse pressure with flow. So the first question is, is it pressure, or flow, blowing on you in some manner?

To give you an understanding of the pressures involved in therapy I'd like you to try this.

Get a tall glass of water and a straw to match, A large dring at your favorite fast food will do.
Now simply blow bubbles.


Any trouble? Didn't think so. Assuming the straw was 8 inches deep, you just blew out with the maximum pressure a CPAP can deliver, 20 cm of water. A BiLevel typically goes up to 25 cm water or 10 inches depth. Again this is intended just as a practical demonstration of how much pressure can be generated by a CPAP. Not enough to blow up a balloon.

[cathyf]

Kafka, I am obsessed with this phenomenon, and have a thread for it here: http://www.apneaboard.com/forums/Thread-...-your-data
If you look at your flow rate curve at a 1-minute zoom, you can count the breaths and see your real respiration rate. Here's an example:



The median rate is down there in the neighborhood of 14/15/16, and while the machine is totally confused and recording garbage for the respiration rate, it's obvious that my respiration rate is a little less than 16 breaths/minute in this picture.

I'd be really interested in seeing what a zoom of your flow rate curves looks like. Here's an example of mine, where you can see a half dozen normal breaths in between the crazy stuff:





I must say, though, your overall night respiration rate curves are totally amazing! I thought mine were ridiculous, but you've got me beat hands down!

(Note something that I wish I had noticed months before -- if you go to the second tab on the left sidebar, the "Events" tab, on the bottom is a slider and you can set the zoom level to an exact number of minutes. I don't know how many hours I wasted trying to drag-and-click an exact time so that I could compare wave shapes!)

[Geer1]

With your machine there are two pressures. EPAP which is the pressure during exhalation and IPAP which is pressure during inhalation. EPAP is what provides a constant pressure which holds your airway open preventing obstruction. The increased pressure to IPAP during inhale and decrease back to EPAP during exhale make breathing against the pressure easier. On your machine set pressure = IPAP and EPAP = IPAP - EPR.

Since EPR makes it easier to breath you want to use 3 EPR. Your min pressure of 7 cm with 3 EPR gives a min EPAP of 4 cm which is the lowest pressure the machine can provide. It is very possible that you need a higher min pressure and the change between 7 and 10 cm of pressure is not very much but you can try something in between first if desired. If you are worried about the pressure then leave max pressure limited to 13 or 14 for now.

You never responded about the leaks, do you know what causes them and why they are almost always present? They seem better but still small amounts regularly present.

[Kafka82]

With your machine there are two pressures. EPAP which is the pressure during exhalation and IPAP which is pressure during inhalation. EPAP is what provides a constant pressure which holds your airway open preventing obstruction. The increased pressure to IPAP during inhale and decrease back to EPAP during exhale make breathing against the pressure easier. On your machine set pressure = IPAP and EPAP = IPAP - EPR.

Since EPR makes it easier to breath you want to use 3 EPR. Your min pressure of 7 cm with 3 EPR gives a min EPAP of 4 cm which is the lowest pressure the machine can provide. It is very possible that you need a higher min pressure and the change between 7 and 10 cm of pressure is not very much but you can try something in between first if desired. If you are worried about the pressure then leave max pressure limited to 13 or 14 for now.

You never responded about the leaks, do you know what causes them and why they are almost always present? They seem better but still small amounts regularly present.

I inspected the machine and tubing and seem fine - I can only assume the leaks are due to face interface with masks - I guess if sleep on the side the mask can push against the pillow and move a bit. Also the beard factor a bit but I keep the mask quite tight so not too sure here.

[clownbell]

May I ask how old the mask cushion is? Medicare provides for replacing a full face mask cushion every month. I realize you may not be on Medicare. And I realize that many members here go longer with their cushion. I only mention Medicare parameters as something to look at. Every once in a while I read of a member who has used their cushion for a LONG time and wonders what the problem is. Masks can lose their ability to seal well if the cushion is too old. Something to consider.