Interpreting OSCAR, Clusters of Central Apnea

[letsrun100]

Here is my data from last night. I changed minimum pressure to 6 and EPR to off as suggested. The CSRs and CAs seem to be a pattern as well as the absence of OAs. I felt like I slept well, and don’t remember waking up during the almost 7 hour period.


I’m going to call my sleep doctor today and ask him to review my data. I don’t have a scheduled appointment for another two weeks.

   
   

[Gideon]

Ok, now it's time to talk ASV. Likely he will wait until you have used CPAP for 2 to 3 months the time it typically takes for treatment emergent Central Apnea to fade.

Ask him if the plan includes an ASV and how you will get there. You have so far failed at CPAP and will fail at BiLevel.

ASV is the only machine that will actually treat Central apnea.

An ASV titration study is a very good outcome.

[SarcasticDave94]

If ASV is the goal, you need to aggressively but respectfully push hard on getting it ASAP. Waiting a few months for treatment emergent to disappear doesn't sound like that will change the need for ASV. My personal shortcut was legitimate consistent complaints that the BPAP was not working. I was not getting better with greatly compromised comfort. I stated it was not acceptable. I failed BPAP in less than 1 month by order of complaints.

[Sleeprider]

We see many members with these central apnea problems end up with a prescription for a bilevel (BiPAP) ST (spontaneous/timed). This is NOT a device that can or will help you, so jusst be aware of it, and try to get ASV (adaptive servo ventilator) therapy. Your doctor shoul start making arrangements for an ASV titration now as it may take some time to be scheduled.

This link is to the Resmed Sleep Lab Titration Protocol Guide. https://www.resmed.com/us/dam/documents/...er_eng.pdf This has good information on the kinds of machines that are available for therapy. I'd like you to try to understand the differences between CPAP, Bilevel (VPAP), VPAP ST and ASV. The concepts are pretty simple and will helpy you discuss your issues with your doctor more effectively. Please focus on ASV therapy and how it applies to complex apnea, central apnea and CSR breathing.

By reading the protocol, you will see how pressure should be raised for certain events, or what kind of therapy is needed for specific problems. If you look at the flow chart for CPAP, you will see that when central apnea are present, the recommendation is to move to ASV. By understanding these simple flow charts you can tell your doctor that you have looked at Resmed's sleep study protocols and can see ASV looks like the right decision. What you want your doctor to do is to arrange for a sleep lab titration test that includes ASV as a possible endpoint.

[letsrun100]

This is certainly turning out to be more complicated than I anticipated. But I want to get to the bottom of this and get my health on the right track. I thought I was pretty healthy. I’m a young 72, I walk 60+ miles per week training for a 48 hour and a 72 hour race coming up this summer. I’ve been a runner and ultra runner for over 40 years. I have not had a stroke, I (hope) do not have a brain tumor, viral brain infection or chronic respiratory disease. My cholesterol is a controlled with low dose statins and my calcium score is 62.

I have a few questions, if you please.
1)      I had a home sleep study. I’m wondering how a simple pulse ox sensor (that’s all I had) on my index finger can accurately diagnose OSA? Or is it more complicated than that?

2)      I was told that I had moderate Sleep Apnea = 25 incidents per hour. Assuming this was accurate and I did have OSA, is it possible that my two weeks of CPAP therapy has eliminated my nightly OSA occurrences?

3)       Is it possible that I am now experiencing CAs because of CPAP therapy?

4)      How does forcing air via ASV, CPAP or any other mechanical method treat Central Apnea? I thought the brain’s signal to breath comes from a build up of CO2. I should take a physiology course.

I only started getting SD card data from my machine about three days ago. I found out the card must be “in the machine” while collecting data, not after the fact. All I got were the AHI numbers until three days ago.

I requested this morning (via MyChart) that my doctor review my sleep data from the past two weeks. I assume he has been getting the data transmitted to him daily from my machine.  I also sent him OSCAR reports showing the CAs and CSRs, and lack of OAs from the last three days. This may show him that I have at least some knowledge about my data other than what MyAir sends out. I told him my AHI numbers for the last two weeks are unsettling for me and I want to make some changes rather than wait another two weeks before my follow-up appointment. My AHI numbers =  10-11-8-34-26-17-19-14-14-11-12-14-7 and last night 8.

I requested his opinion just this morning, so I don’t really expect a response today. But if I don’t hear anything by mid-day tomorrow, I’ll follow-up with a phone call.

I am reviewing the Resmed Sleep Lab Titration Protocol Guide and feel I can, or will be able to discuss the different levels of treatment. Thank you for sending it. A titration study seems appropriate at this point.

Thank you all for your valuable input.

[SarcasticDave94]

1. If it were a lab sleep study as a contrast, there would be chest belts to measure breathing movement or lack of it. There would also be brain wave monitoring as well. A SPO2 meter by itself probably would not be nearly as accurate.
   
2. A CPAP related device can give therapy to eliminate events, but only as long as you use the CPAP. It does not ever cure you from apnea disappearing forever. And, yes, a CPAP can cause an immediate reduction of apnea events. If it does not, there is a problem.
   
3. You are describing treatment emergent CA events. Many apnea patients suffer these while beginning CPAP. This is due to a greater ventilation efficiency than was existent prior. A CPAP can wash out CO2, giving a false sense that breathing is not needed currently, hence a CA event. Is that what you're getting? I don't recall the details of your discussions here.
   
4. The CPAP class of device increases pressure on the throat to create an air splint, which causes it to remain open. If it's held open, it will not collapse and cause restrictions.
   

[Sleeprider]

I'm going to give you a slightly different take than Dave. First, you are a healty, fit man with no apparent comorbidity for obstructive sleep apnea, yet your pulse-oxieter study identified events in the form of oxygen desaturations and possibly pulse increases at a rate of 25 per hour. Those events could have been obstructive apnea, hypopnea or central apnea. I'm going to suggest your baseline condition consists of all of those, with probably mostly "central hypopnea" where your respiratory drive just slows for no known reason (idiopathic). With CPAP therapy, we expect that obstructive events are often resolved at low pressure, especially with normal-weight individuals, but that hypopnea often convert to central apnea, and CA is not treated with CPAP. This is not our first rodeo with thin, fit, athletic individuals having central sleep apnea. Your CSA is not indicative of an underlying pathological, neurological or physiological problem, it just happens at a low frequency in the population and is very poorly understood.

The only way to really know your baseline condition is to perform a sleep study with polysomnography that will reveal the extent and types of apnea. That may be the next step in the process rather than ASV titration, because for Medicare to approve ASV, you must first have an appropriate diagnosis. At this point you have qualifying disordered sleep breathing that was ASSUMED to be obstructive sleep apnea. ASV works by providing sufficient baseline pressure to keep the airway patent and to prevent obstructive apnea, then adds pressure support (increased inspiration pressure) to make breathing comfortable and easy. On a breath by breath basis the Resmed ASV will increase or decrease the pressure support to maintain your minute vent (amount of air respired in L/min) and can replace your breathing effort if there is no spontaneous respiratory effort. So if you are breathing normally, you get low pressure CPAP and a little pressure support. If you are breathing too shallow you get more pressure support to increase your respired volume, and if you stop breathing, you get more pressure support to ensure you take a breath. It's brilliant and comfortable and results in near zero events for most people with your problem.

[letsrun100]

Again last night zero OAs and MANY, MANY CAs and AHI = 25.29.

           

I spoke to the Respiratory Therapist from my doctor’s office. We went over my data and she suggests not making any changes until I have my follow-up in two weeks. I should just be patient and we will see how things go. As far as a Titration study, the hospital sleep lab is not doing any sleep studies at all right now because of the COVID virus.

I am having a terrible time with both of the full face masks I have, F20 and F30i. I seem to sweat under the masks and there is just too much bulk on my face. I just cannot get comfortable with either of them. So, I ordered a Dreamwear Nasal CPAP Mask and should have it by Friday. 

Now, will my AirSense 10 need to be reprogrammed to accommodate the new mask? My Therapist suggested that no changes need to be made. Any other opinions?

Thanks in advance.

[SarcasticDave94]

There's a setting for the type of mask, Full Face, Nasal, Pillows. Just change that according to the type. If the RT asks, you did change that setting due to a new mask. It should not make any difference to them.

[Gideon]

Complain,
You DO have CSR, not just periodic breathing .
Call and ask how you can reduce your Cheyne Stokes Respiration.
Your AHI from centrals is nearly 1 every other minute! How is your sleeping when something's going wrong with your breathing every other minute.?

Ask about the distribution of centrals on your sleep study. Do you perhaps have a recording oximeter? It wouldn't be a bad idea to record overnight.