Breathing pattern identification, Flow limitations and posture

[SingleH]

Hi all,

First post here and had a few questions I wanted to ask regarding my father who has sleep apnea.

Background info:

Male early 70's , slim, 5ft 10, 180lbs
Previous heart failure due to valve failure, surgery successfully corrected and now heart function classified as normal. All parameters of blood pressure, oxygen, heart rate rhythm now normal.
Scoliosis with forward head posture/kyphosis. 
Last sleep analysis advised moderate positional sleep apnea, 20 AHI. Sleeping on back worse than sleeping on side.
Wears a foam cervical neck collar.

When using CPAP, he gets good results when sleeping on his back with pressure around 13-14 but CPAP machine increases pressure to maximum range setting when he is on his side, which is contrary to what his sleep study stated in terms of his position. I can only assume that when he sleeps on his side something is happening to his mask which is causing a problem. He gets a lot of flow limitations which I believe are happening on his side, as he says when he first goes to sleep, he sleeps on his back but when he wakes up in the night he tends to go back to sleep on his side.

Mask leaks normal, but pressure above 17.5 seems to start causing problems with leaks. 

Prior to his surgery in the final weeks he developed Cheyne-stokes respiration which went away after his surgery and there was a drop in AHI also, however he continues to have a strange shallow stuttered inhalation. Nobody has been able to give any advice in regards to this. Since OSCAR now works with the F&P Sleepstyle I have gotten the info off his machine and wanted to post an example of the breathing pattern as it doesn't look like the ones in the OSCAR Wiki.

1. Can anyone identify this breathing pattern.

2. Could the collar cause flow limitations or make the positional apnea worse?

2. Should EPR be enabled to help with the Flow limitations, as I saw recommendations for that in the other posts here.

Any advice appreciated. Thanks!

[attachment=53409]        

[Sleeprider]

When posting charts, please minimize the monthly calendar to allow more important data to show below the date. Maximize EPR and let's take a look at the difference. You have multiple peaks in inspiration and your machine can't track whether you are inhaling or exhaling and has an very high respiration rate as breaths are being counted multiple times. By all appearances here, you have severe Type II flow limitation which is a partial or full obstruction during inspiration that cuts flow, then the airway reopens giving double and triple peaks. It's some of the worst I have seen and is usually loose tissue in the esophagus. This article describes classification of flow limitation and yours is described in Figure 5, Table 1 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4688581/ Let's see the difference with EPR, but I think you actually may benefit from a true bilevel.

[Gideon]

+1, agreed.

[SingleH]

Hi Sleeprider,
Thanks for your response and explanation.  


I have posted a couple of screenshots with the calendar minimised, hopefully that provides more info. These are previous days, so not including any EPR changes as yet. There are some strange looking patterns in the breathing pattern screenshot.

Its interesting you noted the machine cant track inhalation or exhalation as looking when he inhales, one inhalation is actually like a series of very brief small inhalations and exhalations until his chest is full and then an exhalation. Prior to his surgery I recall they said his chest capacity was a little small which I believe is due to his scoliosis hunching over his back and shoulders combined with weak inspiratory muscles. He has a strong forward neck posture also so his neck is bent in the middle if he tries to look up and he has problems swallowing sometimes, so I think your comment about some obstruction in the throat is probably true also.

EPR is now set to maximum and will see how that goes.


           

[Sleeprider]

In the close-up graph of flow rate we see multiple inspiratory peaks. The flow rate rises normally then falls to near zero, but not into exhale. To see this even better, you can improve the flow rate graph by adding a zero-line. Right-click near the y-axis (vertical numbers near the graph title) and select Dotted-Lines, then set a check mark at zero. This will place a red line in the graph at zero flow. This is the point where inspiration and expiration (I:E) crossover the zero flow. This is explained in the Beginner's Guide to Sleepyhead here: https://www.apneaboard.com/wiki/index.ph...ailed_look

The CPAP machine is double-counting many of these breaths, even though there is no exhale flow (below the red line). This is a good inhale with an obstruction as flow reaches peak, followed by reopening of the airway and resumption of inspiration. This may require an ENT to diagnose the cause of inspiratory obstruction. We have seen this pattern in some individuals, and I have found a bilevel machine with the capability of increasing pressure during inspiration and having a minimum time of inspiration setting is more helpful than EPR. This enables using more pressure support during inspiration, and maintaining that pressure through the normal time of inspiration. This person is actually breathing at 11 breaths per minute which means we probably need a minimum time of inspiration around 1 second to move past the first obstruction.

[SingleH]

Thanks again Sleeprider and comment about BIPAP noted.

Ive added the Zero line as you suggested and taken a couple more screenshots. I noticed it seems when the pressure is low those "inspriations" seem to go below the zero line more often than when the pressure is high or at least thats how I interpreted it.

I was also looking to see if there is anywhere with a more normal looking pattern and saw there are a few times when it seems to return to a slightly more more normal looking patterns withing the multiple inspirations. I marked that in a red circle.




           

[Sleeprider]

I was thinking about this and played around with simulating it. During nasal inhale, let the back of the tongue rise to the roof of the throat and it cuts airflow to zero mid-inspiration and letting the tongue release restores flow in the same breath. It's a talent for sure! I'm fairly certain that is the mechanism at work here. Normally we use the tongue to seal air pressure from entering the mouth from the airway. This is done by placing the tongue against the roof of the mouth behind the front teeth, so this form of inspiratory obstruction is basically just a misuse of that same position and possibly lack of control. I would suggest trying this with and without CPAP pressure and trying to create the mid-inspiratory restriction, then training how to avoid it. I don't know if this will work, but trying to understand the obstructive mechanism could go a long way towards solving it.

[SingleH]

I think there is certainly something going on whether its the tongue or something else. His neck posture is probably also a big factor. I will see if the technique you mentioend can be worked on.

I increased the EPR in two steps to max settings and I can see his apneas and flow limitations have increased over the past week, so for whatever reason, that function does not seem to help. I didnt get a chance to take screenshots but I will do soon.

I was also looking at BIPAP machines, I saw the RESMED Aircurve 10 BILEVEL model is discontinued and am I ccant make sense of the Philips Recall as it seems there are all manner of models recalled but I see on some websites Dreamstation units for sale.

Have there been post recall Dreamstation models released that are BIPAP machines.


I would like to find a BIPAP unit that is OSCAR compatible. Would you have any suggestions?

Thanks.

[Sleeprider]

The Aircurve 10 bilevels are still the current Resmed machine. No Aircurve 11 has been released, and I'm not sure I would want one. I was issued a new Aircurve 10 Vauto with updated firmware just about July 1.

[SingleH]

The UK supplier I spoke to says its discontinued, but on the Resmed UK site they are still shown, so I think the supplier may be confused as I asked about Respironics as well.

On the UK site there are are three AirCurve 10 Versions, I presume it would be either the S or V model as the CS PaceWave makes no reference to bilevel?

AirCurve 10 S - Fixed bilevel therapy device

AirCurve 10 V -  Auto-adjusting bilevel therapy device

AirCurve 10 CS PaceWave -Adaptive servo-ventilator device