Looking for advice – very high AHI

[sparky2]

I was on CPAP several years ago and was very proactive for over a year. My sleep study showed an AHI of around 70. They gave me a REMStar Series M set to 9 – 13 and sent me home. I noticed that about the best I could do was an AHI of around 7, with the average being around 11. The machine broke and I lost 50 pounds and stopped using it (I know, I know).

Long story short; I broke my leg, got out of shape, and put the 50 back on. I took my machine back to the sleep clinic and they gave me a new PR Series One Auto (model 560). They said that I could try going without another sleep study and they would review where I was after 30 days. The machine was set to 9 – 13. The first night I only slept with it on for about 3.5 hours and woke up in the morning with it off my face (Mirage Swift II). My AHI was 39.9. I chalked this up as a one-time deal, but the next night I slept for about 5 hours with an AHI of 57.9. I have had one night around 12 and one around 18 but the rest of my first 8 nights were with AHIs about 40.

Typical charts follow (I hope):



I called the sleep clinic and they said to come in and they would look at the data. The LPN was concerned and thought I may even need BiPAP. They scheduled a sleep study a few days hence which I completed last night. I will not see anyone for a week and am concerned with continuing sleep with these high AHI numbers until then. I was thinking of adjusting the pressure in the meantime. What do you think?

Thanks in advance;
Sparky2

[Julie]

Have you tried a full face mask? You could be losing all the 'good' air out of your mouth when you're asleep - unless you know for a fact that doesn't happen.

[zoocrewphoto]

It looks like your pressure was topping out most of the night, except when your leak was bad. Your upper pressure limit probably needs to go up.

[archangle]

It looks like your pressure was topping out most of the night, except when your leak was bad. Your upper pressure limit probably needs to go up.

Really BAD idea. He has a lot of central apnea.

Increasing pressure could make the central apnea worse.

Sparky, DON'T increase the upper range on the pressure yourself until you figure out your central apneas.

Zoom in onto the area where you are having lots of central apneas. Zoom in close enough where we can see 2 or 3 minutes of your airflow waveform.

[Pugsy]

Are all your nights showing the same high number of clear airway events? Are you actually sleeping or by any chance are you spending a lot of time awake on the machine?

I am with archangle.....I wouldn't be increasing pressure at all until I knew more about what was going on.

Any chance you are taking any meds that might suppress respiration? Like opiates of some sort?

[zoocrewphoto]

It looks like your pressure was topping out most of the night, except when your leak was bad. Your upper pressure limit probably needs to go up.

Really BAD idea. He has a lot of central apnea.

Sorry about that. I'm not used to looking at sleepyhead reports, so I didn't even think to look for that.

[Todzo]

Print and bring with you to discuss with your doctor:

Gilmartin G, McGeehan B, Vigneault K, Daly RW, Manento M, Weiss JW, Thomas RJ.
Treatment of positive airway pressure treatment-associated respiratory instability with enhanced expiratory rebreathing space (EERS).
Source: J Clin Sleep Med. 2010 Dec 15;6(6):529-38. Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.
Link: http://www.ncbi.nlm.nih.gov/pubmed/21206741

In the mean time do what you can do reduce the stress level in your life.

[sparky2]

Have you tried a full face mask? You could be losing all the 'good' air out of your mouth when you're asleep - unless you know for a fact that doesn't happen.

I have a beard that I would like to keep. When I last was on CPAP regularly a couple of years ago, I had read here that this could be the case. I bought something (perhaps denture adhesive?) and tried that for a couple of weeks with little to no improvement. At that time my AHI was hovering around 11 either with or without the adhesive.

It looks like your pressure was topping out most of the night, except when your leak was bad. Your upper pressure limit probably needs to go up.

This is what I initially thought as well.

Zoom in onto the area where you are having lots of central apneas. Zoom in close enough where we can see 2 or 3 minutes of your airflow waveform.

Below is a snapshot of about 5 minutes in an area where I am having a lot of CA events; about one per minute. This is at a time where the pressure is decreasing a bit. There is a time between 6:30 and 7:15 where there are very few CAs (and OAs for that matter) and that is during a time with the pressure going towards the minimum of something less than 10. The chart cuts off at 10 for some reason. The minimum pressure is set to 9.

Are all your nights showing the same high number of clear airway events? Are you actually sleeping or by any chance are you spending a lot of time awake on the machine?

I am with archangle.....I wouldn't be increasing pressure at all until I knew more about what was going on.

Any chance you are taking any meds that might suppress respiration? Like opiates of some sort?

Most have the same high number. There is one night that shows less CA and that happens to be the night with my lowest average pressure. I have had a bad cough for the last couple of weeks and have been taking an over the counter syrup that contains acetaminophen, dextromethorphan HBr, and doxylamine succinate (Kroger NiteTime Multi-Symptom). I guessed that there may be a correlation between the cough syrup and my performance and, looking at the data, I think my best night was that night (AHI=11.6, Hyp=3.5, OA = 5.7, CA = 2.4). You may be on to something.

I understand that raising from 9 - 13 may be a really bad idea. How about I try changing to 8 - 11 for a night? I realize that this may be a big change and that there is risk associated with it, but going forward expecting another night of AHI = 40 or more does not seem wise either. In any case, I am off the cough syrup!

Please let me know what you think, and thanks for all the help!

[Pugsy]

If the centrals are related to pressure then of course more pressure is probably not the way to go.
Those clear airway events may or may not be related to pressure though....but always best to play it safe until you know what is going on.

If you have had an upper respiratory infection (cough) for the past couple of weeks then maybe what you are seeing is related to the cough. I recently have had a bit of a flu bug myself and my centrals were a lot higher than normal. Mainly I think because I simply didn't sleep well.

The best advice is to wait and see what the recent sleep study is going to point to.
That said...I know I would have a hard time sitting back and waiting... and I would be chomping at the bit to try something.

You know if the centrals are related to pressure then APAP changes are probably not the best way to go. At least that is the general rule until we know if the centrals are real and a real concern.

If it were me I would do a severely limited APAP range (so that I would still have FL data) with something around 8 to 9 cm pressure range. Tiny range really. If we switch to cpap mode we lose FL data. So instead use a tight, tight APAP range.

Also....closely evaluate the quality of your sleep....do you spend much time awake or semi awake?

For sure you need to follow up with the up coming doctor visit to discuss the recent sleep study. If those centrals are the real deal then you have a lot to talk about with your doctor and we probably shouldn't be doing a whole lot of dial a winging here.

[jweeks]

The LPN was concerned and thought I may even need BiPAP.

Sparky2,

Your LPN may very well be right. As others pointed out, you are having a ton of centrals. They are sometimes induced by the pressure. That might put you into a CPAP catch-22 -- the pressure level that is high enough to treat your OSA is higher than the threshold where you start having centrals due to high pressure. BiPAP can dance around that catch-22 by using a higher pressure just on inhale, and a lower pressure on exhale. The higher inhale pressure forces open your airway so you can breathe, while the lower pressure is just enough to keep your airway from collapsing, which puts the exhale pressure below the threshold where you have centrals. The titration for this is pretty tricky, so it is good that they scheduled you for a full sleep study.

There are cases where BiPAP cannot work around the issue. There are more complex machines out there that can help if the BiPAP doesn't work for you.

-john-

[sparky2]

Thanks Pugsy and jweeks. I do not think I spend much time awake, except for the half hour before getting up where “semi awake” sounds about right. It seems that I go in and out of sleep a bit then, but other than that I do not think so. I have gotten into the habit over the years of waiting until I am very sleepy before trying to go to sleep. So I do not think I spend much time awake during the initial period either.

The central/BiPAP issue does sound tricky. I hope that they have gotten all of that figured out from this last over-night study. I do not want to do that again anytime soon. But, rather that than poor health and being tired a lot of the day.

I will have to think about the trade offs between continuing with the present settings or trying something else.

Could my Flex settings have an effect? It is currently set to A-Flex = 1.

[old64mb]

If while under treatment previously your AHI averaged 11, it means your treatment was ineffective then and should have required another sleep study. Since you discontinued treatment anyway, it became moot, but it's no real surprise that previously ineffective settings remain ineffective now.

You've had a cold which can make things worse, it's possible the machine reported clear airway events that are bogus and/or a result of attempting to adapt to xPAP again after a long time away from that modality, but it's all largely irrelevant.

Since you've had the sleep study that should have been done years back, no reason to tweak settings for now. Too many moving parts and better data and recommendations are coming shortly so I'd hold off on that and focus on just try to get used to wearing a mask overnight again until you get results back.

Cheers.

[DavidCarolina]

Two amateur obserations

1. You were successful with cpap before, so you need to find the right machine and mask and see if you can duplicate your previous success. Stick with it, and lose that weight again.

2. Notice your snoring events seem to correlate with a spike of AHI. I have the same problem. You need to address that. Perhaps your rolling onto your back and snoring. Perhaps a dental device would improve it. Perhaps yourr level of sleep is inducing snoring and you need to increase the upper limit of titration to fight off those events. But deal with the centrals first. Solve one thing at a time. I suspect youre sleeping on your back without knowing it.

[Pugsy]

Could my Flex settings have an effect? It is currently set to A-Flex = 1.

As in be a likely suspect for causative factor in all those centrals??? It's doubtful but not totally impossible.

If you had an upper respiratory illness going on during this time frame we have to really suspect any data that you see.

[sparky2]

Faced with the choice of sleeping with my current CPAP settings and likely getting an AHI of 40 or sleeping without the CPAP again and getting probably 70 or trying a change, I opted for the latter. I stayed away from the OTC cough syrup and changed my CPAP settings to 8 cmH2O min and 9 cmH2O maximum as Pugsy said he might do in my position (I realizing that he was not recommending that I do this).

The result was the best night so far. I had an AHI of 10.04. This was made up of Hypopnea = 5.43, OA = 2.21 and CA = 2.41. The charts look as follows:


My plan is to try the same thing tonight unless I hear some other suggestions.

If while under treatment previously your AHI averaged 11, it means your treatment was ineffective then and should have required another sleep study. Since you discontinued treatment anyway, it became moot, but it's no real surprise that previously ineffective settings remain ineffective now.

You've had a cold which can make things worse, it's possible the machine reported clear airway events that are bogus and/or a result of attempting to adapt to xPAP again after a long time away from that modality, but it's all largely irrelevant.

Agreed, treatment is now only as effective as before and I am sure the cold cannot be helping. I have coughing fits during the day and am not sure what happens at night, but probably something.

Notice your snoring events seem to correlate with a spike of AHI. I have the same problem....

Yep. Losing weight is already happening, but very slowly. I will look at the snoring issue in the next few days.

Pugsy, thank you very much for the ideas. I suspected that an A-Flex adjustment would not do anything, but it was worth a shot. I am leaving it unchanged for now. As old64mb pointed out, too many moving parts. I will try to stick with one change at a time. Please let me know if the latest data shows you anything.