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+--- Thread: CSR simple explaination? (/Thread-CSR-simple-explaination)
CSR simple explaination? - drgrimes - 12-25-2021
My AHI scores are fairly low, less than five, often less than one. BUT every once in a while i get a jolt of CSR. I have read lots of discussions about it i'm not sure if this is something bad or not. When i zoom in on the CSR in Oscar, it looks like a very rapid, maybe shallow breathing. Can someone tell me what my body is doing during this event(s)? I have read about CSR on this forum and what to look for in my charts but can someone describe in plain terms what is happening to my breathing during CSR?
RE: CSR simple explaination? - SarcasticDave94 - 12-25-2021
Include a 3 and 10 minute shot of your CSR session and I'm sure someone can go over the details. In most cases, for those that do not have heart conditions, CSR is what I think is also referred to as variable breathing. The PAP is incorrectly labeling it this way, and OSCAR just reports it as such.
RE: CSR simple explaination? - Sleeprider - 12-25-2021
Resmed flags many variations of periodic breathing as CSR. It's not CSR! True Cheyne-Stokes Respirations are generally found in congestive heart failure and it is a gradual increase in respiratory volume which is the hyperventilation part of the cycle, followed by gradual reduction of respiratory volume ending in a central apnea. The pattern repeats. The hyperventilation phase flushes carbon dioxide from the blood and causes chemical changes that result in diminished respiratory drive triggering the central apnea which causes a an increase of carbon dioxide leading to the next hyperventilation phase. In some people, there is just a delay in the feedback loop between breathing and the chemical receptors that drive the respiratory volume and rate, so that the need to breathe is out of phase with the actual need. It is very common to see oscillations in breathing volume following respiratory events, but the oscillation are usually less than what causes Resmed to flag CSR and are of short duration. We also see members that are near their central apnea "apneic threshold" as a result of increased ventilation from CPAP or BPAP, and the same mechanism is at work there with a delayed feedback loop.
Periodic breathing can appear similar to CSR in that there is a repeated waxing and waning of respiratory volume, but usually not ending in central apnea. We have seen periodic breathing that begins with an apnea, hypopnea or flow limitation which increases CO2, followed by recovery hyperventilation, and a repeating oscillation of respiratory volume.
Another more complex explanation is found in this NCBI article https://pubmed.ncbi.nlm.nih.gov/29411336/
Quote:The pathophysiology of CSB has been explained by the loop gain theory, where a controller (the respiratory center) and a plant (the lungs) are operating in a reciprocal relationship (negative feedback) to regulate a key parameter (partial pressure of carbon dioxide (pCO2)). The temporal interaction between these elements is dependent on the circulatory delay. Increased chemosensitivity/chemoresponsiveness of the respiratory center and/or augmented ascending non- CO2 stimuli from the C-fibers in the lungs (interstitial pulmonary edema), overly efficient ventilation when breathing at low volumes and prolonged circulation time are involved.
RE: CSR simple explaination? - drgrimes - 12-26-2021
SarcasticDave, I hope i did the screen shots correctly. I am attaching a 3 minute, 10 minute and a normal. I have mostly low ahi's with no CSR, but as i said i will have a few scattered nights with CSR and higher AHI. I have had tests done by cardiologist who says my heart is perfect. I am in good health, am 74 y.o. and exercise for one hour everyday. Am also normal BMI. I have almost no obstructive apnea, most being CA.
[attachment=38375][attachment=38376][attachment=38377]
RE: CSR simple explaination? - SarcasticDave94 - 12-26-2021
If you have no heart conditions, as was likely you didn't, these CSR will be false flags and represent periodic breathing.
It does appear your Central Apnea/CA will be your far bigger issue. CA are known to be consistently inconsistent just like your up on the 23rd and down on the 24th. Do you have your diagnosic sleep study detailed report? You can post it and we can work on this CA issue. If the CA are pre-dominant, you can get better therapy on ASV if the CPAP therapy you have now isn't doing well for you.
RE: CSR simple explaination? - Sleeprider - 12-26-2021
I agree with Dave and the type of periodic breathing you have is the type we see with individuals near their apneic threshold as I described above. This might be reduced by using a lower EPR setting. You are currently using EPR at 3 and you may have less of these periodic or CSR flags and fewer CA events, by using a setting of 1 or off.
RE: CSR simple explaination? - drgrimes - 12-27-2021
Dropped EPR from 3 to 2. I also changed min/max pressure up a bit to 6/10. I know thats pretty low but i learned a long time ago, with higher pressures i suffer with terrible leaks. The min/max pressures that show on my profile are very old and out of date. I got better results with lower pressures.
I realize these good results are only one night. Results could bounce around still, but i am impressed with better resiults with small changes. I know better than to get over confident with so little data.
I added my SPO2 results. I am using the WELLUE unit but it does not let me bring results into OSCAR.
[attachment=38403]
[attachment=38404]
RE: CSR simple explaination? - Gideon - 12-27-2021
You are having unexplained pressure excursions. Please add flow limit chart and remove the AHI chart. Everything we need to see charted on AHI we see in the events chart.
I suspect your pressure excursions are the result of flow limitations which can be fixed by increase in EPR, what you just removed, so I'm not making a recommendation to change settings, just to be aware.
Keep these settings and see how you feel .
RE: CSR simple explaination? - SarcasticDave94 - 12-27-2021
I know there's some method to get your Wellue imported to OSCAR but I myself don't remember the steps involved. Stay tuned, someone else will let you know. The oximeter stats look good on this particular post. The pulse seems a bit elevated to me.
Now onto OSCAR stats. I suggest unpinning AHI and show this order: Events, Flow Rate, Pressure, Leaks, Flow Limits. AHI can be monitored on the left panel instead of the detailed trace on the right. More important info is needed like leaks and FL.
I think you're doing yourself a disservice by avoiding to deal with a leaking mask, and by possibly compromising therapy by lowering pressures. Leaks are still going fairly high at 20.x, so you need to address it. Your avoidance plan isn't working as well as you'd like. You need to consider addressing several areas of mask leaking issues, proper strap adjustment that is never too tight, uncomfortable, or painful. Never. Too tight ain't right. It could be a worn out cushion or headgear, then replace it. It may be wrong sized. It may be the wrong shape, in which case you need to replace it. It could be the wrong type, pillows, nasal, full face, hybrid. I've had a lot of success with Fisher and Paykel masks. They're comfortable, low leaks with minimal strap tension.
RE: CSR simple explaination? - Sleeprider - 12-27-2021
Results with the lowered EPR seem to have stabilized your breathing so that you don't have periodic oscillation of volume, or what Resmed flags as CSR. I suspect your ideal minimum pressure is between 6.0 and 8.0 and you can sort that out in time. I don't recommend chasing flow limits in your case, or we will be looking at the CSR and central events again. This looks great, and I think you should hold pat on these settings, or consider a minimum of 7.0.