Picking up where I left off - My CPAP Therapy Thread

[SwirlySauce]

Trigger sensitivity to Very-High. Next step is to reduce PS to 3.4.   Let's take one step at a time.

Thanks Sleeprider, I'll give it a go tonight.  Lack of good sleep, stress at work, and bad OSCAR numbers really got to me this week 

Appreciate your help with this.

[SwirlySauce]

Hi Sleeprider,

I've been away from my machine for a few days but I will provide further charts soon. I have some questions that I've been trying to find answers to on the web the last couple of days. I'm hoping you might have further insight into these.

1. If Central Apneas are caused by more efficient CO2 clearing, does an increased Trigger setting actually address the root cause of the issue? With a higher Trigger setting it seems easier to trigger an inhale which, I'm guessing, makes it easier to "snap" out of a CA when it occurs. However, due to PS you're still clearing out CO2 more effectively regardless with every breath. Wouldn't this still be bad for the body healthwise? I'm not sure if my assumptions on how trigger helps are correct.

2. If a lower PS is needed to reduce CAs, can we use a higher EPAP in combination to help reduce Flow Limitations?

3. Can TiMax also be used to reduce CAs? If your inspiration is limited by lowering TiMax, would this reduce CO2 clearance?

4. Does Cycle have any impact on therapy effectiveness? I saw you mention in another thread that this is used for patients with respiratory issues like COPD to protect expiration. Google searches of this setting also seem to refer to it as a comfort feature in some instances, and I found some users that were able to fix their CAs by using a combination of high Trigger and high cycle. I find a high cycle seems to align better with my breathing pattern but will have to see if reduces my therapy in the long term.


Apologies for all the questions - the further I dive into the world of UARS / BiPAP the more questions come up!

[Sleeprider]

I'll do my best with this. The Vauto is not approved for most of these "off-label" function, and they are mainly discovered through personal experience and coaching over the years.

1. A high trigger setting means IPAP is triggered with less spontaneous inspiratory flow. In fact, I have found "expiratory rebound", which is not even a real thing, can be sufficient to cause enough pressure increase to stimulate a breath. We can speculate that this might slow down the respiration rate enough that CO2 can rebound enough to resume normal respiratory drive, but that seems like speculation. We'll call it a working hypothesis.

2. Higher EPAP or pressure is a conventional CPAP approach to mitigate hypopnea, RERA/flow limits and snoring, so yes. This is standard titration protocol.

3. TiMax will not reduce CA, it can extend the time inspiration will continue until spontaneous cycling, without the machine returning to EPAP based on time. We use TiMax for comfort where normal inspiration time is greater than the default 2-seconds or shorten it when we want to conserve more time for expiration. This is more complicated than it seems. We want to avoid disruption for those that need an occasional long inhale without feeling the machine is causing them to cycle, but we also don't want to extend inspiration time into hyperventilation.

4. Cycle sensitivity is rarely used except for those that tend to hold on to inspiration longer and need to feel the release of IPAP. It is extremely rare we use it, and I can't think of any specific case where I have suggested it. I see some members experiment with this and it usually really screws up their sync.

[SwirlySauce]

Thank you so much for the detailed explanations, that helps a lot!


I've attached OSCAR charts from the last two nights.  This is with Trigger [Very High] and Cycle [High].

Good news is there weren't any reported events for both nights - which is a record for me!  Bad news, I felt pretty exhausted on both mornings but I'll work on keeping my mask on all night.  Still struggling with waking up wide awake throughout the night and I end up taking my mask off.

I'm also seeing much fewer flat-toped inspiratory flow shapes (as compared to my old DreamStation).  But what I am seeing are not nice sinusoidal shapes either.  Lots of sharp peaks, slanted mountains, and general rough looking shapes.  (See 'Shape')

Are those a concern?


Thanks!

[Sleeprider]

The close-up respiratory wave form you posted is textbook perfect and normal.  Expiration is at high volume and gradually decreases to near zero where the graph levels off. What looks like a bump ahead of inspiration is a typical null-flow. Inspiration looks very good with no occlusion or resistance through the peak flow, and declines rapidly into expiration.  On 2/10 from 00:00 to 00:30 we see what looks like some periodic breathing. This is where the centrals would have occurred without the very-high trigger.

Looks great! Keep at it and no changes for now.  Just for future reference, this chart would be a lot better with Mask Pressure instead of pressure. That would show the machine response to your respiration on a breath by breath basis.

[SwirlySauce]

Thanks for taking a look SR!  I've swapped around Mask Pressure in my charts for next time.  Will keep settings the same and report back with an update in a week.

Forgot to add, while going through my flow charts I've noticed these oscillating, wave-like patterns that occur throughout the night.  Not sure if they are of any significance but I've seen them on my old DreamStation as well.

They're very obvious when looking at the flow chart in 5 - 10minute intervals.  Any idea what those are?

I promise that'll be my last question for a while.

[Sleeprider]

Very common periodic breathing, often associated with being near the apneic threshold. In its severe form you might see some hypopnea or CA where the flow dips. In this case, it is what it is...normal fluctuation of respiratory drive.

[SwirlySauce]

Thank you

[SwirlySauce]

Hi Sleeprider,

I came across 'S Mode' while reading about something called EasyBreathe in the user guide for the AirCurve. From what I understand it can only be enabled in the S Mode.

Is it beneficial to switch over to this S Mode so I can EasyBreathe or should I stick with VAuto?

[Crimson Nape]

Easy-Breathe is enabled when it is Vauto mode. Having it on, is very uncomfortable.

- Red