Cheyne Stokes Respiration ?

[Mal777]

I have worked with other forum members with high respiration rate that exceeded 50 BPM and was resolved with ASV. Here is an example from member Hojo. http://www.apneaboard.com/forums/Thread-...#pid223896  Your most recent post gives us some new information to consider.  We have looked at your periodic breathing episodes and concluded they were not CSR, but a high frequency oscillation of respiratory volume with no flagged apnea at the low point.  It is true, you have not had significant central events flagged with CPAP use, and I reacted to the recent sleep study with ST where CA was flagged as pressure support was increased.  Yocu have shown charts that include very erratic respiration rates and volumes, and also a "normal" respiration that is frequently flow limite and an unsteady respiration that often gets counted as multiple breaths within a single respiratory cycle.



You correctly identify that ST helps with hypoventilation that seems to occur during REM Sleep, and observe that ST-A iVAPS mode was not tried, and that iVAPS might be easier to tolerate.  I agree ST-A is a more appropriate fit and can vary its pressure support to target respiratory volume and rate, and also back off and allow more spontaneous breathing.  ST-A would be a better choice for ensuring a more stable breath volume and rate.  Since the ST-A includes the ST mode you have been recommended, this machine would fulfill your current recommendations and provide another therapy mode, iVAPS, that may end up being better.  Based on prices posted by Deepbreathing, it seems the incremental cost of ST-A may not be much more, especially the refurbished unit.  I think it is certainly worth a try, and I think in the end, the iVAPS mode will be the therapy of choice. I am not a fan of fixed, high pressure support like in your titration. It's hard to imagine that could be a good long-term solution, and a 64 minute titration trial is not a good indicator of success.

Thanks again Sleeprider
I am slowly gaining an understanding of whats going on, and why I am so tired all day after therapy with my Airsense 10
See my sleep physician in around a week, so will know more about what to ask him. He should be happy with ST-A I think

[Geer1]

The comment was specifically about hypoventilation in rem. This wouldn't show up in median value, you would only maybe notice it in minute value charts as being a decrease in minute volume during normal rem times (periodic every 90 minutes ish and increasing in duration later in the night/morning).

[Sleeprider]

FYI, there is an Aircurve 10 ST-A with 1314 hours being sold on the website Dotmed for $1750 and a S9 VPAP TX with 1656 hours for $750. The Tx is a titration machine with all therapy modes available including CPAP, Autoset, VPAP-S, Vauto, ST, T, PC, iVAPS and ASV. In other words, the ultimate does everything machine. Supplier #2 has a S9 VPAP ST-A for $1249 that includes a one-year warranty, and we know they support their overseas sales.

[Mal777]

RLS = restless leg syndrome
PLM = periodic leg movement

Both are movement disorders that can cause arousals/sleep disruption.

Either you are having some sort of periodic obstructive apneas (some sort of obstruction that happens then your body finally forces a breath, hyperventilates to compensate for lost breaths then the process repeats) or you are having central apneas. This last data says obstructive but most of your earlier data pointed more towards centrals. One thing I have noticed looking at my grandfathers data is that it seems like these machines have some trouble determining central from obstructive in these situations(periodic breathing) especially if there are leaks present (which there was during your main obstructive period).

Your breathing issue in this case is either obstructive in which case higher pressure or larger pressure support (recommendation by sleeprider for bilevel) would be the solution. The machine has already hit your current max of 15 cm and that didn't help so you could try setting max pressure higher to see if it helps, maybe it is something positional and a cervical collar might help too). If central in nature it may be being caused by EPR. I will agree that your last data looked more obstructive in nature but your original data looked more central which is why I was curious if adjusting EPR might make a difference. Raising pressure or pressure support(bilevel) would only make centrals worse and I still think it would be worthwhile to try a reduced EPR just to see if it seems to have any effect. If it doesn't then that would indicate the issue truly is obstructive and a bilevel, increased pressure or cervical collar should be your main focus, if it does help then things change a little.

Hi Geer
This is an earlier post of yours...

"I would be curious if this periodic breathing would go away with reduced EPR which would imply that these are central apneas being induced by the CPAP treatment (I don't know that I believe the obstructive flag for these). They could be being caused by the increased pressure as well as it seems you might be more prone to these events at higher pressures.

You mentioned you feel it is harder to breath with reduced EPR. What you could try is turning ramp back on, setting it to auto, start pressure to 8 cm and EPR to ramp only. This will help you fall asleep and then once you do the EPR will turn off. "

I tried it again last night (EPR on, ramp auto auto and ramp to EPR only) and my centrals were  lower than usual . I maxed out on pressure of 15 a lot more though so will increase pressure max to say 18 tonight. Also my RR was even worse than normal. 

Have attached last nights screenshot for your opinion

thx again

[Mal777]

A quick question please

I realise they are very different machines and the Vauto does not have a backup rate, but are
there any features on the Vauto that I will not be able to replicate on the ST-A (ivaps). ?

[jaswilliams]

The ST does not have easybreath and is a fixed epap/ipap machine so no auto function

[Mal777]

I heard the ST-A (in IVAPS mode ) does have an auto function?

[jaswilliams]

I heard the  ST-A (in IVAPS mode ) does have an auto function?

Epap is fixed PS can change and increase to maintain volume. It is not the same as auto in a VAuto where Epap is raised to treat OSA.

[Sleeprider]

The Vauto is an excellent, comfortable and effective machine for obstructive sleep apnea, and like the ST, it provides pressure support in any amount needed to assist respiration. A key difference is the lack of any backup rate and the fact pressure support is delivered in proportion to spontaneous effort (the mask pressure mirrors the patient flow rate). This means if you don't breath spontaneously, the machine won't trigger a breath, and when inspiration is weak or unsteady, so is the pressure support. One way to think of it is, for hypoventilation or central apnea, the patient needs pressure support that is inversely proportional to effort for flow in order to maintain a target on minute vent, so when effort is weak or non-existent, pressure support becomes greater, or in the case of ST does not change. The Vauto has no volume or rate targets and relies entirely on spontaneous effort to deliver therapy and pressure support. We cannot manipulate tidal volume or breath rate with the Vauto, but we certainly can with ST and ST-A.

ST delivers the same EPAP and IPAP all the time and triggers IPAP on a timed basis.
iVAPS delivers fixed EPAP and adapts IPAP to maintain minute vent or alveolar ventilation, and triggers IPAP using an intelligent breath rate that brings the patient back to the target rate, but allows some variation in breaths per minute.
Vauto delivers variable EPAP and IPAP maintaining the same PS all the time, however it has no backup rate, and PS may not be fully delivered when respiratory effort is weak or obstructed.

[Geer1]

Mal, regarding your post on EPR increasing EPAP will only help if your airways are collapsing. If flow limitations not affected by pressure are driving up your pressure than it wont help.

EPAP is the minimum pressure that is maintained by the machine. This minimum pressure is what holds an airway open. In people with obstructive apneas and other situations that are caused by the airway being allowed to close it is the most important setting.

EPR or PS are pressure differentials that allow for increased flow through restricted airways. When increasing EPAP no longer helps open an airway up further than EPR/PS must be relied on to speed up flow and provide required ventilation through the restricted airway.

Next available feature are timing controls. Some machines are capable of providing PS faster or slower, sooner or later and maintaining it for a set amount of time or turning it off after another set amount of time. With Resmed these features are called rise time, trigger and cycle sensitivity, Timin and Timax respectively.

Next feature available is backup rate. Backup rate initiates PS if you don't take a spontaneous breath within a set amount of time. Backup rate is what fights central apneas and it can sometimes overcome obstructions well.

These are the features all Resmeds machines use.

CPAP provides set EPAP and EPR which is capable of treating consistent obstructive sleep apnea.

APAP adds self adjusting EPAP for people that have varying levels of obstruction in different stages of sleep, in different sleeping positions or from night to night.

Basic bilevel machines like the S model are effectively a CPAP machine with the ability to provide larger PS and timing controls.

Vauto is an APAP with larger PS capability and all timing controls except for rise time.

ST is like the S version with backup rate. As Sleeprider mentioned I believe it has a timing function to provide PS at exact times too but haven't seen it in action yet(also not sure if it is mandatory, I have assumed it is an option).

ASV in ASV mode provides set EPAP and in ASVauto provides auto EPAP. ASV also has backup rate but no timing controls. The big difference with ASV is that it has variable PS that works to maintain 90% of your recent ventilation requirements. This is what makes ASV the machine of choice for complex sleep apnea as the combination of backup rate and variable PS can deal with both obstructive and central sleep apneas and the programming of 90% means the machine still requires the patient to be able to maintain spontaneous effort so doesnt act as a ventilator. If you aren't capable of maintaining spontaneous breathing than the only feature that helps is min PS (by making it easier to breath).

Then there is the ST-A which is an ASV with timing controls and instead of targetting 90% of spontaneous ventilation it has a set minimum ventilation that it aims to maintain. This is what makes the machine capable of dealing with hypoventilation.

ST, ASV and ST-A are all capable to some level of dealing with your breathing issues. The ST might work but I don't really like you having to use a high PS just so the machine can treat rem hypoventilation(assuming that was technicians conclusion, if it wasnt their recommendation doesnt make sense). The biggest problem with high PS all the time is that it is going to cause lower co2 levels which causes the centrals. The backup rate can minimize the flow issue regarding centrals but it doesnt account for other low CO2 effects which sometimes seem like they may be an issue(joeywallaby being one potential example on here and other studies like the one he posted on diamox support the idea). l also don't like that it will be extremely difficult for you to self titrate with an ST since you pretty much would need EEG data and have to try to interpret data to understand if the hypopneas are an issue or not. The titration in that situation would seem counterintuitive to most(not trying to minimize hypopneas).

ASV would be my machine of choice but only if it is capable of dealing with the strange breaths and hypoventilation periods effectively which I am not sure it would do. I would definitely want to trial one and maybe have a titration study done as well (mainly if hypoventilation is deemed to be a main issue). You could set a high min PS which would do same thing as ST to help maintain ventilation but you run a higher chance of running into over ventilation issues if doing so.

ST-A is the only machine that can do it all and the only downside is that it can act as a ventilator and is also trickier to set up and titrate. I like it because it allows for lower PS when your spontaneous breathing is occuring which will minimize the centrals and low co2 periods. It is also the only machine truly capable of dealing with periods of hypoventilation.

Hopefully that helps understand features and options a bit more. As stated ASV would be best but only if it can provide good enough results. For the one stated issue (rem hypoventilation) self titration will be difficult, ST-A is easiest as you just increase target ventilation and see if it helps. I personally would be pushing doctors to try and understand their recommendation (why is the substantially higher hypopnea and RDI count acceptable, how much of an issue did the hypoventilation appear to be, did timing controls appeae to be important and why would ASV or ST-A not be better options).