APAP Setting Query

[johanlon]

Greetings:

My wife has been using a CPAP since '87.  The first ones were loud and manual, but they did the job. Initially her pressure was set at 7 cm H2O.  When that machine died in early 90's we received a Puritan Bennett manual unit--compact and tidy for travel. Some 5 years ago we switched PC physician to a small group of 2 docs that are part of a nationwide elite medical group. Excellent care.  His first action was to have her take an overnight polysomniogram and have a sleep specialist (a physician) analyze its data.  That doc changed pressure to 13 cm. However, he seemed most interested in keeping his "7-minute appointments" on schedule. Her then-current DeVilbiss CPAP with expiatory pressure relief seemed to help at this pressure setting. Specialist doc gave no advice on EPR setting, which is customer variable from 0-3 cm below fixed pressure. Neither did the DME "sleep technician" who said to set it where we liked. We messed with various masks and found that a full face mask (QuatroFX) worked well at this high pressure--the EPR (-3 cm) was an asset as it reduced leaking. I am concluding that sleep specialist physicians know very little about hardware.

Side bar: Don't blame the DME sleep tech for machine you are offered--blame their company policy!


Since mid Dec she has been using her new ResMed Airsense-10 For Her. She feels much better with this machine.

Fast forward to this week: As posted in the software part of this forum, we never were able to read the detailed data from her unit until Jan 1.  (We can now see the summary data from first use 16 Dec.) Have viewed with ResMed and SleepyHead software, both work fine.  

After looking at the data I see that for most evenings AHI was not very good.  Most recent nights AHI was in the range 3.4--7.2  A few nights were very high. with numbers of 17, 10, and 10.2 on three nights.  looking further at the data we see that Clear Airway apneas (CA) were more common that OA. Very few H. Most nights CSR breathing was 0% but on two nights it was 10 and 13%.   Her machine was set to start at 4 cm, and operate in the range 4-20 cm.  Recent data shows it spending most of its time in the range 7-17 cm. (We have no idea how these data compare to those of her last sleep study many years ago.

My understanding is that auto-adjust machines increase pressure in response to reduced airflow--e.g. an OA, or other cause of reduced airflow. This tells me that CA's - even many in a row - are not being treated.

One other interesting correlation in this limited set of data relates to the health of the user on those few days when AHI was very high.  One day correlated with being ill.  The recent two days with AHI=10 followed a dual vaccination for flu and pneumonia booster, for which her arm became very swollen and caused her to feel quite poorly.  Do we know if physiological stress in a patient with sleep apnea causes (daily) changes in AHI?  Do we know if any meds affect CA?

Examining data can be like peeling an onion--each answer leads to more questions!   And yes, I think I will receive more help here than from the DME or any doc no matter how good they are.

Comments and suggestions welcome.

JO

[DeepBreathing]

Hi Jo. Welcome to Apnea Board.

It would help us immensely to see the actual numbers for these nights, in the form of #SleepyHead daily charts. The fact that your missus is having an excess of central apneas could indicate a change in her health status, requiring a different treatment approach. Alternatively it could be that the relatively high pressure combined with a high EPR are inducing these central apneas. Standard CPAP and APAP (autoset) machines do not treat central apneas. They diagnose them (at least the better ones like your Resmed) but do not treat them.

You mentioned the machine is set to 4 - 20 cm H2O pressure - this is termed "wide open" pressure and does not allow the machine to optimise the treatment. A narrower range will almost always result is a superior outcome.

But first we need to get those centrals looked at, and for that we need the SleepyHead charts.

[ajack]

I would also turn down the epr to 1 or even off if you can, it often settles some of the CA.
If the pressure range is 7-17. Try 7 or a bit under the median number. This would be a first minimum pressure I'd use, till you get some charts up

[Walla Walla]

Also to answer your question about medications. Yes there are many medications that can cause centrals. I'm not an expert but if you could list the types of medications someone here could probably give you insight to any that could be a problem.

[johanlon]

Thanks greatly:

In response to providing SH data: I see an "export" icon. Does one simply export the data to desktop and attach to a reply?

will try raising base pressure to closer to average and dropping EPR to 1 and observe.

Am still interested in knowing if short-term physiological issues can affect sleep patterns

Thanks,
JO

[OpalRose]

johanion,
There are tutorials in my signature line to show how to take a #SleepyHead screenshot, upload it to
Imgur and post here.

Pay close attention on the organization of the graphs. Take a screenshot of the daily page. We need to see the following graphs: events, pressure, flow rate, leak rate and snores. Leave off the calendar.

Until you have 4 posts, leave a space in the link from imgur. Example: h ttp .....

[johanlon]

Here are links to Imgur-images of four SH screen shots. 2Jan--5Jan
These are for my wife, who has used a CPAP for 30 years, but finally has un-corrupted SD data to view.
Bottom part of SH chart does not show; missing info is 
* Full face mask Quatro-Pro for her, 
* humidity level 2, 
* EPR on, level -3 cm H2O



[img.png]http://i.imgur.com/E9lN2Mch.png[/img]
[img.png]http://i.imgur.com/EgkfNyLh.png[/img]

Thanks, look forward to hearing your comments.

JO

[OpalRose]

The first thing to try is turn EPR to 1 or off.  This may help with the Clear Airways.
In answer to your statement about Clear Airways...an Apap machine will not treat them, just flag them.

I would also narrow the pressure range, especially the max pressure.  Bring it down to 13 max.

[ajack]

I'm not going to be much help. I would keep the min 8 for now and still reduce the epr to 1 or 0. See how it is in a week. There is a bit of clustering, some may be positional and respond to a soft foam cervical collar. I wouldn't at this stage, to me it's wait and see for a bit.

Although your wife has used cpap for a long time, she hasn't been on these pressures, They may well just be pressure induced central and settle down within 12 weeks. Also the good and bad nights indicate to me that it may just be the body getting use to the new cpap pressures and I'd let thing settle down for a while.

You ignore anything while going to sleep/waking up or awake. the cluster at 6am in the second chart may have been while awake.

[johanlon]

Again, thanks to both commenters:

She has been at 13 cm for many years; it's just the machine that's new. And yes, getting adjusted to a new machine was one of my thoughts when I look back at the only data (summary) available between 16 Dec and 2 Jan, that is, the AHI bounced around quite a bit for first few nights. eg. 7.4, 8.9, 17, 8.6, 5.6, 5,7, 3.4, 4.6, and so on.

I will reset min P and EPR and watch for a week. 

The EPR seemed like a great thing for people with high pressures as it reduced pressure on exhale, which in turn helped keep mask seated. That said, I can see how it interacts with breathing rhythm .

Again, thanks,
JO