What Apnea Malady Each Machine Type Can Handle

[JustaHoseHead]

Greetings,

   As an introduction, I have been a CPAP user since 1994 (diagnosed AHI 120 at Scripps Medical Institute).  I have used a number of different manufacturers' machines and tried most masks.  I felt I had a relatively low AHI 0-2.5,  but after a cold/virus bug, decided to look at my flow limitations as I thought they affect my sleep efficiency.  (It seemed that my Resmed S9 APAP produced better results than my  Resmed A10 APAP.)  In viewing the breath waveform on the A10, I see that it shows a partial collapse on inspiration which may have always been there, and I am wondering if I can correct this.

  Question 1)  Is it true that given any type of mask (full face, nasal, nasal pillows) , with sufficient pressure with APAP,  a very low flow limitation (less than 0.05) can be obtained.  Another way of asking this may be "Can adequate pressure eliminate collapse of the inspiration portion of the breathing waveform in nearly all cases".  (My suspicion is that if the breathing interruption is neurogenic in origin, pressure might not be able to accomplish a correction.)

  Question 2)  Can the different types of machine VPAP, VAuto, Aircurve be typified in layman's terms as to what malady set they each address best.   A corollary question might be "At what point of adjusting pressures on an APAP machine can a person realize that they should be on another type of machine".

  (I have used the Soft Response mode of my A10 when I felt that the Standard Response might be too aggressive and causing some CA/HA.  it appears that for me it really functions chiefly as a 'CPAP mode that allows you to add EPR'.  I have the Corflex and Releaf ALT cervical collars.)

  Thank you for your help.

Justahosehead

[Gideon]

Welcome to the forum.

Q1. The mask has little to do with function and the correct mask is, seriously, the one that works for you.  Very good readings, including flow limits, can be obtained with any mask as long as it fits you and your breathing.
Pressure/pressure support/EPR (not Flex) adequately optimized on the correct machine for your condition (ASV for significant Central/Mixed apneas), I'm assuming your "breathing interruption is neurogenic in origin" is central.  CPAP/APAP/BiLevel all work based on maintaining pressure to "splint open" the airway, ASV works by maintaining your breathing volume via the algorithmic application of pressure support and pressure.
Obstructive Apnea is treated with EPAP or Exhale Pressure.
Flow Limits, hypopneas, RERAs, UARS are treated with Pressure Support, the higher inhale pressure/the difference between exhale and inhale pressures.  ResMed CPAPs are limited to a max of 3cmw, BiLevels can go much higher.

Q2. As to which machine for which malady, read this Wiki Article
http://www.apneaboard.com/wiki/index.php...estriction

When to pick another machine.  For obstructive events when a CPAP is just not working a BiLevel is then used for "non-compliant OSA".  For this we usually suggest the VAuto.


In some "lucky" individuals the use of a xPAP device may initiate central apneas via lowering you CO2 concentration in your blood to below the apneic threshold..

All of the above comments are generic.  To be specific please post OSCAR nightly charts for evaluation.  

[JustaHoseHead]

Thank you for your reply.  Exactly the info I needed!

[JustaHoseHead]

Need some help here. My APAP seems to prevent OA, but something else may be going on.


I have adjusted my Resmed Airsense10 (Autoset) to try to reduce the number of events, using the EPR. I see some collapse on inspiration (the PAP not splinting open the airway even under these high pressures, almost on all breaths, showing raggedness on the top of the inspiration hump). In addition I see a lot of respiratory work being required in these episodes where resp rate increases and tidal volume shows large decreases (each with about 40 minutes duration occurring an hour after the last one, 3-4 per night) The first plot shows the standard layout. The second shows the large tidal volume decreases (plot is made with median at the top)., with large minute volume ventilation with decreases in total volume and flow limits which do not seem to be very large. The third plot shows an OA apparently without a flow limit.


(My Airsense10 is brand-new, and seems to be often incapable of reliably storing a full night's record on the CD, and I have made arrangements with the DME to replace it with another new unit, but am waiting to see if I may need a different type machine.)

I would be grateful for your interpretations.

[JustaHoseHead]

Here is the screen shot showing the breath waveform that exists for 99% of the duration of a night's record.   (There are perhaps 5-8 periods of 3 to 10 breaths which show a smooth waveform).

[Gideon]

You are mouth breathing.
See the second from the bottom chart.
http://www.apneaboard.com/wiki/index.php...eathing.29

The "Standard" charts (View/Reset Graphics/Standard) include the leak chart and that one should be presented.

Read the Mask Primer on Mouth Breathing. http://www.apneaboard.com/wiki/index.php..._Breathing

[Sleeprider]

The flattening of the inspiratory wave form is classic flow limitation caused by obstruction or resistance in your airway that limits the peak inspiratory flow.  It may be nasal, or in the throat or other source.  I don't know why the FL statistic is so low given the shape of this wave-form. You are already using the full range of EPR available, so adding more pressure support would require a bilevel machine.  The challenge becomes identifying the source of this flow limitation and dealing with it if it is positional, or using a higher pressure support to mitigate it and make a greater peak inspiratory airflow possible.

[JustaHoseHead]

Thank you for your guidance (s) !

(The leak graph shows no leaks {zero throughout the whole night)}  except when I take the mask off, even if I set the y-axis ranges 0 to 0.1.  I cannot find any leaking.)

I tried using my S9 last night since my A10 does not record reliably.  On the S9 I used machine min pressure 13, EPR 3, and got nearly the same results, except that I had 4 ten-second CA events, and the breathing waveform looked a little nicer.  Will post the screenshots later.

[JustaHoseHead]

       
Here is my S9 data from last evening.  It seems that the low-level flow limitation (between the large flow limit bundles) is what is showing up on the degraded-inspiration breathing waveform.  I think if I did not have the bundles of excursions in the tidal volume (ie, if the whole tidal volume trace were nice and quiet), that might be a metric to indicate when I have improved the flow.  I may try different FFMs to see if I can make a change.  Still, I have come a long way since my days of AHI=120.

[Sleeprider]

The way the "bundles" or clusters of flow limitation occur, I suspect chin tucking. It's not so severe I'm going to say run out and get a cervical collar, but just be aware that is the likely mechanism.