Finally had a proper sleep study - Please help interpret results

[nearenough]

Hi everyone,

I finally had an in-lab sleep study done and I could use help understanding the results.  

When I discovered that I had apnea, my initial diagnosis came with a prescription for an auto-titrating CPAP with far too broad a range of pressure settings (4-16 cm).  You all helped me dial it in to 13 cm with EPR=2, and now my AHI now hovers around 1.5 or less.  My AHI is good, however I still wake up every day feeling exhausted.

My primary care physician ordered an in-lab Bi-Level study thinking Bi-Level with greater pressure support could help with the chronic fatigue.  My redacted lab results are attached and I could use help understanding the results, and how to act on them.  My primary care felt it was too far outside his expertise to offer an interpretation, and I don't have a sleep specialist.

I have a prescription for a bi-level machine that I haven't pulled the trigger on yet because I have to pay out of pocket.  Before I make the purchase, I'd like to know if you all think Bi-Level would help with my daily fatigue, with my CAs and pattern breathing, etc.  I'm less inclined to spend the money if bi-level therapy won't change things substantially.  

My previous (consolidated) therapy post has examples of a typical night at or around 13cm + EPR.  I'm happy to include more screenshots, but I figured it would be best to keep it simple and start with the lab results.

A few noteworthy points

• I'm a runner and have a low resting heart rate, and I'm on a beta blocker due to apnea-induced PVCs.  My Sleeping heart rate is normal for an athlete.
  
• I had no idea I needed to be concerned with leg movement (PLM?).  I have no idea what to do in response to the data.
  
• I'm in Denver, 93-95% SpO2 saturation is typical at night.
  
• I tend to have primarily CAs and lots of periodic breathing since beginning therapy in June; very few apneas and hypopneas by comparison.
  
• What do I make of the lab result of an AHI of 18 at 14/8?  
  
  

Again, I'm new to lab results.  My first test (June) was at home and only measured breathing and SpO2.  The lab was far more comprehensive, but I don't know what action to take on the data.  My health spending account should have enough to purchase a Bi-Level device next month, but again I'd prefer to drop the money if it would improve fatigue, CAs, etc...

Thank you for your insights and recommendations on the test results.

[Gideon]

That is a prescription for a device that is not intended to treat Central Apnea and states your diagnosis is OSA.

Please post a daily chart from your AS11 ( do you have another thread I need to search for?) And a copy of the sleep study.

[nearenough]

There is more than just the prescription if you scroll past page 1 of the PDF.  There is a full writeup from the tech who evaluated the data.

Previous therapy thread:
http://www.apneaboard.com/forums/Thread-...apy-Thread

[Sleeprider]

Looking at the study, all events were CA, and it seems the main criteria for selection of the titration pressure of 13/7 (PS 6.0) was the presence of REM sleep and absence of events. I like to look for linearity in results through titration, and there is a huge red-flag here where your highest AHI was just 1-cm pressure higher 14/8 than your titrated pressure. CA events related to pressure support tend to be random and I think that was the case here. It may be a coincidence that your best results occur at 13/7 rather than any relationship to efficacy. Given the type of apnea you experience, I think that in the long-run you will do much better with PS 4-5 than PS 6. This titration study shows obstructive sleep apnea and RERA and stable SpO2 is resolve d at the minimum pressures of 9/4 and 9/5. I think this study shows an optimum pressure occurs at 11/6 to 13/8, and I do not think you will tolerate more than PS 5 long-term.

[YouTakeMyBreathAway]

One thing I wanted to call out is that once you get your BiPap, look into trying to change the Trigger Sensitivity to "Very High" - this resolved virtually all the CA events I had.

Given all the events are central, I'd also be curious to hear from experienced members here why this isn't indicating trying ASV?

[Sleeprider]

ASV is not going to be approved for CA at this level. More than likely all of the CA events can be titrated out by using PS or trigger sensitivity, as was your experience. Bilevel seems to be more indicated here for better sleep related to flow limits and RERA.

[Gideon]

I've just reviewed the main therapy thread, a real pita on a phone I'll add.

I really like where you are at now.

Make sure you get a ResMed VAuto for a BiLevel.  Your Rx is written for a BiLevel without backup.  It reads as a BiLevel "S".  A VAuto will also do "S" mode but please make sure you get the ResMed VAuto.

VAuto is important because it has a Trigger setting that may be very helpful in suppressing central events but...

Step#1: get a baseline with the BiLevel first

Step#2: if indicated, initially set Trigger up one level to High then evaluate.  Incrementing not just setting to high.

Step#3: if indicated, szet Trigger = Very High then evaluate

Evaluations are both subjective and numbers.

To all readers, the OP indicated in his therapy thread that his diagnostic sleep study resulted in a OSA diagnosis with OA and CA split 50/50.  This means IMHO that his diagnosis should have been 

Primary: "OSA"

Secondary: "CSA"

This doesn't mean that his centrals are not CO2 related, but that they existed pre-Cpap.  That and seeing indications of both idiopathic and hints of CO2 influenced breathing prompted me to request the longer trials with and without EPR.  

I and others saw little influence from EPR increasing Centrals.

[nearenough]

I was incorrect about the 50/50 OCS vs CSA back in that old thread.  My original numbers were:

OSA - 103
CA - 28

So at the time of diagnosis it was more like 4 to 1, almost 3 to 1, but not 50/50

Hypopneas - 119
Hypopneas 4% - 5

[Gideon]

So what were the indexes, per hour values. That is much more informative than counts since we don't know what your sleep period was so we could do the math.

[nearenough]

Total Apnea Index - 23.5
Hypopnea Index - 21.4
Hypopnea Index 4% - 0.9
CA Index - 5 (11%)
REI 4% - 23.4
AHI 4% - 24.4
AHI 3% - 44.9