Trying to lower AHI and keep them there

[Maniac007]

Need some help to get AHI under better control or is the CA's not that big a problem. I have been on a ResMed A10 Autoset since June 2015.  Started chemo and radiation in Sept of 2015 and still taking chemo every 21 day cycle.  As long as there is nothing new or nothing grew, this is what I will be taking for a very long time.  Here is the last 5 days of SleepyHead charts, hope I did them correctly.  My DME and Dr are discussing putting me on the ResMed Aircurve 10 ST-A bilevel.   

 

[Sleeprider]

Before getting the ST, turn off EPR or turn it down to 1.0 Do this tonight. If the CA is resolved by this simple move, I assure you the ST will make it worse, then apply the "band-aide" of pressure support to cover up the increased apnea.

The correct therapy for central apnea is ASV (adaptive servo ventilation). I don't know why we have recently seen an up-tick in individuals coming to this forum with a recommendation for ST when ASV is clearly superior. The reason ASV is far better is that it promotes spontaneous breathing in individuals with CPAP induced central or complex apnea. It includes the ability to achieve efficacy with lower pressure, auto-EPAP pressure to resolve the obstructive component, and a variable pressure support that applies only the pressure support needed to resolve central apnea, hypopnea and periodic breathing variations. The ASV targets the user's own respiratory rate and volume to apply pressure support to maintain a normal breathing rate, rather than a "timed breath" as done in ASV. Pressure support in ASV is as low as zero on a breath by breath basis, and is variably increased just enough to resolve events. In ST you get the brute force pressure support on every breath.

The ST machines use a fixed pressure support on every breath to reduce respiratory effort and promote a more complete breath. The problem is, pressure support (a change in pressure between EPAP and IPAP) actually causes central apnea to be worse in many people, particularly the complex apnea patient. This makes them more reliant on the timed backup rate, which increases the pressure support when a spontaneous breath is not taken at the rate set in the machine. ST is far more suited to individuals with restrictive lung dysfunctions (COPD, Asthma etc) than the complex apnea patient who develops CA when challenged with PAP therapy.

You should immediately eliminate the EPR on your current machine and see if this resolves the CA. If it reduces CA and does not introduce OA and H events, then start dropping the maximum CPAP pressure until the best results are achieve for all events. If your doctors continue to advocate the ST-A machine, be sure to ask why they are not using the more proven and superior ASV therapy approach. There are multiple studies pointing to improved efficacy with ASV which is a more modern automated PAP therapy that is rapidly replacing the use of ST.

[Amdx64]

This is like my life all over again 

[Maniac007]

Sleeprider, thanks for the info.  I was using epr at 2 but with copd it felt like i was gasping so I took it to 3.  If I set epr to 1, should I bring the max pressure to aound 16 cmh2o?  This would give me a low pressure of 8 and max at 16.

[Sleeprider]

COPD makes the need for pressure support more logical, it also means you are not a typical complex apnea patient. The ST-A is an updated version of BiPAP ST that uses an intelligent pressure support similar to ASV, but has the ability to target the ventilation volume (iAVAPS). Given the complication of COPD, I have to defer to your doctor's choice of the ST-A. It would be interesting to ask them why this is a better choice than ASV. Also the ST-A is a much more intelligent solution to the older BiPAP ST machines with fixed pressure support and timed backup, rather than the adaptive functionality available in the new ST-A ("A" being adaptive).

With that out of the way, I understand why you are using EPR.

I was using epr at 2 but with copd it felt like i was gasping so I took it to 3. If I set epr to 1, should I bring the max pressure to aound 16 cmh2o? This would give me a low pressure of 8 and max at 16.

Increasing the maximum pressure would probably not change your therapy. The APAP will only increase pressure if it senses flow limitation or other changes associated with obstructive events. With your pressure at 10-20, your maximum pressure is only about 11.5. The only way to achieve higher pressures is to set it as a minimum pressure or fixed pressure.

Your apnea is predominately central, and the experiment suggested in my first post was to evaluate if the CA could be diminished by removing pressure support / EPR. If you still want to see whether you respond to to less EPR, my recommendation is to try a lower fixed pressure, and see if this is tolerable with the COPD, and if it reduces central apnea events. If you set your machine to CPAP mode at 8.0 cm with EPR at 1, I think you will see fewer CA events; however it may make it feel harder to breath. All you can do is try it, and see. If this setting is not comfortable, just switch back to Autoset mode and your old settings will still be there. With the lower pressure, you will feel less "assist" when inhaling, but also less resistance when exhaling. Take a look at what this does for events, and as I said, you can move back to the existing APAP pressures just by changing mode.

Let me be clear, I was not aware of the complication of COPD when I made the previous post, and the use of ST-A makes much more sense and should give you some comfortable relief, and should resolve CA events. It would still be interesting to ask how this would compare to ASV in your case.

[TASmart]

The EPR is expiration reduction of pressure - are you gasping on the inhale or the exhale? Also, did you have an in-lab titration to determine the max pressure before CAs start? I would start by lowering your max pressure to 10 and see what the CA do at a lower caped pressure. It looks like your pressure is maxing out at about 11 and that's when the CA are occurring.

[Maniac007]

The EPR is expiration reduction of pressure - are you gasping on the inhale or the exhale?  With copd its hard to breathe in or out  Also, did you have an in-lab titration to determine the max pressure before CAs start?  Had sleep and titration sleep study done a year ahalf ago.  Wasnt diagnosis with all the problems I have now.  I would start by lowering your max pressure to 10 and see what the CA do at a lower caped pressure.  It looks like your pressure is maxing out at about 11 and that's when the CA are occurring.

TonTonight the EPR is set to 1, and pressures are 8 to 15. Tried 7 to 10 a couple months ago and it wasn't working for me.