I need some advice about Central Apnea

[vsheline]

several months ago I went through a sleep study. The sum total, I was having 59 AHI. I averaged not breathing 32 seconds an episode with the longest period of not breathing, 1.36.

Nine days ago I spent my first night with the ResMed S9 VPAP S using a Quattro mask. ... I now have a average 9 day history of:

7.2 hours of sleep
15.18 AHI which breaks down to Apnea = 0, OA 2.22, Hypoapnea .28 and finally Clear Air or Central Apnea = 12.68. The last two days....I have slept on either one side or the other and my OA has gone to less than one and Clear Air to 9 for a total of 10 AHI plus a fraction.

... I plan to talk with my physician about the Resmed machine that forces a burst of air when one does have these episodes. I also found out Medicare is not going to approve it's use without a fight, audit, and denial and more fight. The cost is 6,000 and if need be I would boy one.

Hi eoverstreet, welcome to the forum!

Regarding Adaptive Servo Ventilator (ASV) machines, the type of PAP machine which is designed to optimally treat any combination of obstructive sleep apnea plus central sleep apnea: In the USA the cost to Medicare for an ASV machine may or may not be $6,000, but if you were to buy one on your own without coverage by Medicare the cost to you would be a little less than US$ 2,000 from Supplier #2. (A link to our Supplier List is at the top of every Forum page. It is provided purely as a service to members, as there is no commission or financial gain for Apnea Board when vendors on the Supplier List are used.)

The two leading ASV units now on the market are the PRS1 (Philips Respironics System One) BiPAP autoSV Advanced (I would recommend the newest model which is the DS960S, or DS960HS if humidifier is included, or DS960TS if humidifier and heated hose is included) and the ResMed VPAP Adapt (I would recommend the newest model 36037, or 36047 if humidifier is included, or 36057 if humidifier and heated hose is included -- definitely not discontinued model 36007 36017 or 36027, since the discontinued model does not automatically adjust EPAP like the new 36037 or 36047 or 36057 model does and like all PRS1 autoSV Advanced models do).

Back to my advice - knowing my limited info.....what would you advise, especially those of you who have a similar apnea issue.

Your bi-level prescription, 18/14, has two pressures, the higher IPAP (Inhalation Positive Airway Pressure) and the lower EPAP (Exhalation Positive Airway Pressure). On some machines the difference between IPAP and EPAP is called the Pressure Support. On other ResMed machines the difference between IPAP and EPAP is called EPR and is limited to values of 0, 1, 2, or 3. Bi-level machines allow this difference to be larger, usually up to at least 10.

The EPAP exhalation pressure needs to be high enough to prevent obstructive apneas, which are most likely to start at the very end of exhalation and at the very beginning of inhalation. (We usually are more likely to need higher pressure whenever we sleep flat on our back.)

It usually helps for the IPAP inhalation pressure to be higher than EPAP, both to help us to breathe in more easily (which makes therapy more comfortable) and to help prevent something called RERAs (Respiratory Effort Related Arousals) which are not apneas or hypopneas yet can prevent us from achieving deep restorative sleep.

Central apneas may be induced (caused) by the presence of PAP therapy, but this usually resolves itself (gradually disappears) over the first few weeks or months of PAP therapy. If, after a month or two of PAP treatment, your CAI (Central Apnea Index or average number per hour of central apneas) is still above 5, I suggest you ask for an ASV titration and ask for your machine to be upgraded to an ASV model.

For your own records, ask for copies of your prescription and the full sleep report (including data plots) from your sleep study. You have every right to receive a copy of these for your personal records.

Some people have central apnea events even during their base line sleep study, the part when no PAP therapy was being used. For example, this was the case for me. And during PAP therapy I continued to have CA events, even after years of therapy. Because my CAI was above 5, I was able to obtain a prescription for an ASV machine, which I paid for myself, since my health insurance company does not cover "mild" cases when the CAI is less than 15.

I think Medicare in the USA would cover ASV in your case as long as the CAI is higher than the OAI (yours is) and as long as the CAI all by itself is higher than 5 (yours is) and as long as an ASV titration has been performed and has shown that ASV treatment is effective in your case.

By the way, as far as I know, a central apnea which lasts for, say, 30 seconds is not worse for the body than an obstructive apnea which lasts an equivalent amount of time. In fact, it makes sense to me that a 30 second obstructive apnea probably would have been worse than a 30 second central apnea, because a central apnea would have ended as soon as we tried to breath, but an obstructive apnea might not have ended until there was a more severe strain on our body (in the form of a strong shot of adrenalin to cause us to breath more forcefully, causing a damaging build up of stress hormones and greater overall stress on the heart).


Alternatives to using an ASV machine:

If you are able to ensure that you will not ever sleep on your back (which is usually when higher pressures are needed), for example by wearing a teeshirt with a tennis ball in a pocket sewn right between the shoulder blades, then it is likely your prescribed pressures could be reduced without causing the number of obstructive apneas to increase significantly. On some people, lowering equally both the IPAP and the EPAP will lower the number of central apneas they have. On other people, lowering the pressure does not help.

Another approach would be to keep EPAP at 14 but decrease IPAP slowly (reducing IPAP by 1 cm H2O every two weeks or so) to see if the CAI will drop significantly. On some people, reducing the difference between IPAP and EPAP will very significantly reduce their CAI, although it tends to make inhale harder and will require getting used to the lower IPAP level.

At the same time, when reducing the difference between IPAP and EPAP it is important to monitor how you feel when awake (your level of tiredness or fatigue), since reducing the difference between IPAP and EPAP can reduce sleep quality by increasing the number of RERA events. RERA events do not show up as part of the AHI. (I think ResMed machines do not report RERAs, but I think some PRS1 machines do.)

Take care,
--- Vaughn