Please Help Me With My Settings.

[shallbreathe]

Recently got the home study done and an Airsense 11. I have severe apnea:

Obstructive Sleep Apnea (G47.33) - Severe based on pAHI=46.8 and O2 nadir of 79%
Central Sleep Apnea (G47.31) - Mild based on pAHIc=9.9

As I struggle to get used to this machine (waiting for a new mask) I'm concerned with my altitude situation (6000 feet).

Has anybody's central apnea been resolved with a CPAP (or another machine) while still living at altitude? I have learned altitude affects central apnea...and not sure how a CPAP would actually resolve this if true.

I am constantly waking up just as I fall asleep. Without end. With or without the mask on. I get sleep, feel myself stop breathing, and then wake up from a huge intake of air that follows.

In any case I wonder if I should start looking to move so at least the CPAP would work for me at sea level, and if I'm just wasting time fiddling with CPAP settings here without much resolution and progressively deteriorating as I keep missing sleep.

Thanks for your time.

[SarcasticDave94]

Welcome to Apnea Board,

There may be some edits that might help you. Would you consider getting the free app OSCAR to post a chart?

Was your sleep study at similar elevation as where you live?

Depending on how badly the Central Apnea behave, there's been some success with a VAuto bilevel by way of higher trigger, demonstrated to help some CA. Then there's the ResMed AirCurve 10 ASV, which is designed to treat CA. I've used one for 2 years a while ago, and it's just about as easy to adjust for yourself as CPAP.

[AndyB]

I live at 600' but regularly stay at 9500' in the San Juan Mountains in southwestern Colorado. I use a ResMed AirCurve 10 VAuto and have the trigger set to "very high". I was diagnosed with severe sleep apnea and often had CAs; now, after setting the trigger to very high, I rarely have any CAs even at 9500'.

[Sleeptechmaster]

You don't need to move you need to have an in-lab study while wearing CPAP to further your diagnosis to central or mixed apnea.

What you are experiencing while falling asleep would be sleep onset central events. CPAP can't treat centrals and will worsen them or even sometimes cause them to happen when you wouldn't normally have them.

Central and mixed apnea is more difficult to diagnose from a home study.
Complex apnea is when centrals start happening once starting CPAP.

Bilevel will also make this worse.
If your obstructive events can't be controlled at a pressure of 15 then you would need bilevel (ST) mode. Otherwise it would be an ASV machine. That's a pretty high obstructive AHI for asv though not all of your hypopneas might be obstructive.

If your cpap machine detects a hypopnea that is actually central in nature it will increase the pressure which will actually force these mixed hypopneas into pure central apneas.
Bilevel (ST) mode is like standard bilevel which can allow the pressure higher than CPAP but it has a programmable respiratory rate (called backup rate) which will detect when your breathing rate falls below that threshold and then at that point it begins initiating breaths on its own. If you are above that respiratory rate it functions the same as standard bilevel.
ASV can only control obstructive events at or below a pressure of 15.
With that obstructive AHI you likely are needing around 18 to 20 to control everything.
It would be important to see if those centrals are just during onset and arousals or if they are continuing through the night but anything over 50% would indicate use for those different machines.

[SarcasticDave94]

shallbreathe,

My mistake earlier, I didn't pick up on the home sleep test aspect, just the test being taken. You may benefit from an in lab test. Best if it's near the same elevation as where you live.

If you need to go from CPAP to bilevel, I'll disagree with Sleeptechmaster on ST. If you need to go bilevel, the VAuto should be sufficient. ST machines are reserved for users that have a lung disease and need timed breath. And having had it myself while in lab, it'll be quite disruptive. Further, it is not the answer to Central or mixed Apnea.

If you do need Central Apnea treatment, then ResMed AirCurve 10 ASV will be the answer.

[Sleeptechmaster]

You are right (ST) is geared more towards specific lung diseases but it can be used and has rare use cases to be superior for certain complex, mixed or central patients.

ASV superior example: person who experiences varying breathing rates during different sleep stages that require constant central support. (12 bpm in stage 2 and 15 bpm stage 3) it's also geared towards cheyne stokes and more purely central patients. Occasionally I will see a patient that ASV is unable to be able to keep their respiratory rate up where it should be. It would continue falling very low. In those cases they benefited from the constant regular backup rate of (ST) and we're great once a proper respiratory rate and pressure was found. ASV also has trouble with patients who have a very high respiratory rate like 20 to 30. If they are severely obstructive ASV can only provide up to 15 EPAP which for those certain people would still have very disordered sleep. REM has very low central apnea risk but severe osa so they could get quickly interrupted rem periods.

Bipap (ST) works good for those that have a constant and regular breathing rate through the night. It can provide the rarely needed ipap maximum of 25 for those with very severe osa. It has many additional settings that can be changed. (rise, ti settings, trigger and cycle) If those are fine tuned correctly they can increase comfort a fair amount. Also the set backup rate should be set 2 to 4 below your breathing rate so it should not be noticeable if set correctly. But right now I use (ST) to first pressures to fine tune the starting ASV pressures.

[SarcasticDave94]

The problem is ST is an older, outdated machine that users do better with other machines like ASV for Centrals and ResMed ST-A for lung disease.

Have you tried the ST? It's quite uncomfortable, and being static EPAP and IPAP, you are required to edit pressures frequently. This is old school CA treatment advice in using ST.

[Sleeptechmaster]

That's true that ASV I'd definitely newer and geared toward csa much better. But I still have found times when ST works much better. I haven't used it myself but I have gotten comfort complaints from people when the backup rate is too close to their wake breathing rate. 
Also ASV cannot be used with cardiac patients who have an ejection fraction less than 45%.

[SarcasticDave94]

For what it's worth, your reference to 45% LVEF is still influenced by the flawed SERVE-HF test in regards to getting ASV.

So it sounds like you practice as an RT or similar, correct? You're in possession of some of the same inaccurate but probably well meaning thinking.

[Deborah K.]

My husband and I live at 5700 feet altitude and do very well on our pap machines.  We have gone on numerous vacations that were much higher in the Colorado and Wyoming Rockies and had absolutely no problem.  You can be treated well at much higher altitudes than where you live. I don't think CAs are any different than other types of apnea concerning altitude.

You are going through the normal adjustments that most people have when new to pap use.  It takes some folks a good while to adjust to having a foreign object strapped to their head and face and to having air blown up their noses.  You need to download and use Oscar, a free program that charts every night's sleep.  This provides loads of information on your personal sleep, and then folks here can advise you on settings to change and other things that improve your therapy and comfort.

Don't be discouraged.  You are on a journey to better health.  You can do it!