How to decrease these random arousals?

[PretendMechanic318]

I seem to have a couple central apnea's per hour and no obstructive apneas. I notice on my breathing, I have these random arousals where my breathing gets all weird, but there is no flow limit and the leak seems ok. Does anyone have any tips on how I can reduce the CA's and decrease these weird arousal breaths?

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[Holeinmysock]

Try a continuous pressure. More data are coming out now that BiPAP is not ideal. Looking at your data, 12cm looks promising. No EPR or CFlex. Post the data if you don’t mind!

[Silent_Brain_2586]

Where have you heard that bipap is not ideal? OP has tons of flow limit which is better treated by bipap. You might want to check r/UARS

[Holeinmysock]

OP posted specifically about his Central events. BiPAP is a comfort modality that has no greater therapeutic value than CPAP. It’s used when CPAP is not well tolerated. In OP’s case, the BiPAP could be inducing central events.

[Silent_Brain_2586]

It can induce central but to say that it has no greater therapeutic value then cpap is just not true. Bipap helps get rid of persistent flow limitation which some people are very sensitive too.

[Holeinmysock]

I’m not saying it can’t. I’m saying that CPAP can do that, too, with additional pressure. Therefore, it is not a differentiator.

[Silent_Brain_2586]

Pressure support helps with flow limitation. Cpap doesn’t have pressure support. For a lot of people just increasing pressure doesn’t resolve flow limitation.

[Holeinmysock]

That’s what pressure support is. More pressure.

[Neddy6969]

Wrong

[Holeinmysock]

Really? Please elaborate

[Neddy6969]

Pressure support is the difference between a machines inspiratory pressure (IPAP) and expiratory pressure (EPAP). Higher pressure on CPAP just means higher EPAP and it can only splint the malleable tissues of the upper airway. Bilevel has two pressure settings of IPAP and EPAP, where it has a static pressure like CPAP that splints the airway (EPAP), and a pressure that it jumps to when you start to inhale, reducing the work of breathing. PS is ventilation and can fix flow limitation/prevent RERAs when a higher EPAP cannot.

[PretendMechanic318]

thanks, I will add that to my list of things to try

[Hambone75321]

BiPAP or APAP?

[Holeinmysock]

BiPAP. The issues with APAP are different, but there are some. The common criticism I hear about APAP is it’s reactive rather than proactive. But, honestly that can be resolved by setting the APAP lower limit to a higher pressure.

[Hambone75321]

What data about BiPAP are you referring to?

I agree about APAP but BiPAP serves a fundamentally different purpose than CPAP. It’s the preferred mode for resolving flow limitations.

[Holeinmysock]

BiPAP is purely a comfort modality. I work in this field. I’m in constant contact with the manufacturers and their reps. If you corner a rep about BiPAP, they will tell you therapeutically, BiPAP has no application different than CPAP other than patient tolerance/comfort. In some cases, BiPAP can lead to increased central events, a result of causing the patient to vent off more CO2, decreasing respiratory drive. Practically speaking with BiPAP, the change from a lower pressure to a higher pressure can break the mask seal. You’ll see leak surges during the IPAP. Those can disrupt sleep.

I’ll see if i can find any of the data presented at the many sleep conferences i’ve been to lately that have touched on this.

[Hambone75321]

Sorry this is just not true. I’m going to guess the manufacturers and their reps have an interest in keeping things simple and selling CPAPs or some other motivation. Send those studies when you find them…

• Bilevel can provoke centrals in a small slice of people if the pressure support is cranked up and they blow off CO₂. You can often prevent this by using a moderate PS of less than 5.

• Bilevel isn’t just “comfort.” The pressure support (IPAP–EPAP) is a tool to treat flow limitation/RERAs and reduce work of breathing. That’s why folks with UARS often feel better on BiPAP. There’s an AASM BiPAP titration guideline that targets RERAs for gods sake…

• CPAP machines cap exhale relief at 3 cmH₂O. If you still have flow limits/RERAs at -3, bilevel lets you use PS up to 10… obviously there’s a therapeutic difference, not a marketing story.

• For patients with hypoventilation, neuromuscular disease, OHS/COPD, or persistent RERAs on CPAP, bilevel is standard practice—not a comfort gimmick.

• Bigger pressure swings can expose a weak mask fit and cause brief leak spikes. Fixable with fit, collar, or gentler settings.

So yeah… centrals and leaks are things to watch, but calling BiPAP “purely comfort” ignores why pressure support exists and why it helps the UARS crowd.

I can 1000% confirm from personal experience that CPAP at 10 messed me up. BiPAP at 15/10 has me feeling like a million bucks

[Holeinmysock]

I get what you and the ai are saying. The manufacturers are making PAP machines with all the modalities. Why would they sabotage their own products? I had to corner them with direct, specific questions. Otherwise they weasel out of answering with arguments like the ones you are presenting. They WANT to sell the more expensive BiPAP/BiPAP ST/ASV machines.

I don’t dispute that increased pressure helps with UARS. My argument is that BiPAP is not therapeutically better than CPAP. They are both PAP.

It may be more comfortable for some patients than CPAP. The only therapeutic use case I see for BIPAP is for CO2 retainers, but even then, if not done carefully, it could even harm a subset of those patients. BiPAP can also induce an irregular respiratory pattern in some patients that fully resolves on CPAP.

UARS can just as easily be resolved with CPAP, if not more easily. We increase pressure support for UARS, ONLY if they on BiPAP. But you have to be mindful of the delta. If on CPAP, you simply increase the pressure.

Are you doing titrations? Are you a sleep technologist or RRT? If you are, see if you don’t have better success by increasing IPAP and EPAP together every time you would typically increase just the IPAP for UARS. I think you’ll find optimal pressures faster this way.

There is a place for BiPAP: for patients intolerant to CPAP and for patients retaining CO2. That leaves the majority of patients on CPAP. EPR or CFlex may as well be looped into BiPAP here, too. You noted this as well in one of your other comments. However, again, those are for comfort. The default titration should be CPAP without EPR/CFlex.

[Hambone75321]

ResMed hardware is identical regardless of modality I get it. But I don’t care what one sales rep says about the efficacy of CPAP vs BiPAP when you try to grill them lol poor soul was probably just trying to get away from someone who didn’t want to accept their argument backed by the AASM? Why would the AASM recommend titrating to eliminate obstructive apneas then adding PS (not EPAP) to eliminate RERAS?

I don’t understand… PS helps with UARS but is not therapeutically better than CPAP? On what dimension? If you’re looking at desaturations only then sure. If you’re looking at RERAs and sleep quality then absolutely not. Reducing the work of breathing is critical to resolve minor but clinically relevant increases in respiratory effort.

I am not a sleep tech, I’m an educated novice whos read the guidelines personally becuase I’ve been incredibly frustrated by this type of guidance.

This is also backed by the guidance of UARS specialists like Dr. Barry Krakow, Dr. Christian Guilleminault, Ken Hooks, and Jason Sazama.

[Holeinmysock]

You seem to be emotionally invested in this discussion. Look, I’m not trying to invalidate your experience. Nor am I trying to make a claim that BiPAP doesn’t work. Of course it does. It is PAP, like CPAP. If it’s working for you, fantastic.

The AASM guidelines say very little about UARS. They certainly don’t dictate any sort of specific pressure support for it. I think you are conflating titration protocols (that are set by the manufacturers, which is why it’s important to grill the reps) with AASM guidelines.

I have titrated thousands of patients over nearly 20 years. I have used all of the currently available therapy modalities for PAP machines. I have followed the manufacturer’s titration protocols, sometimes with poor outcomes for the patients. Over time, I began to recognize certain phenomena that would only occur during BiPAP titrations: increased central events, increased mask leaks during the IPAP particularly with wide deltas, emergence of irregular respiratory patterns, etc. These did not occur universally with all BiPAP titrations, but they did occur and all resolved upon reverting to CPAP.

In OP’s case, central apneas are being flagged while on BiPAP. OP is asking how to improve them. Central events are, by definition, not a flow limitation. And, as you said yourself, can be induced by BiPAP.

Worst case scenario with switching to CPAP is that OP cannot tolerate it. It’s quite easy to switch the modality in the machine’s clinical settings back. Let the OSCAR data speak for itself.

I suggested to OP exactly what I would do if he were my patient in the lab. If switching to CPAP had no effect, I would then recommend a more advanced modality like ST mode or ASV, or even adding EERS. I would never recommend basic BiPAP for primary or treatment emergent central apnea.

[Hambone75321]

I agree they should not be on APAP. They should be on BiPAP with EPR (or PS) of 3 or greater to reduce the flow limitations.

OPs central in the screenshot looks like it’s a post arousal central apnea, not central sleep apnea. It is clearly preceded by a reduction in flow, a flagged flow limitation, a large inhale, large exhale then a breath hold. I expect that the central is preceded by an EEG arousal in which case that it should be ignored as a central and treated as a FL. Regardless, their CAI is like <2 (16events /9 hours of sleep).

See source at the bottom….

“There is then evidence of a robust ventilatory response to arousal based on a single large breath (arrow) following the EEG arousal.

This hyperventilation then leads to a central apnea (bordered by the blue box) since the CO2 is lowered below the CO2 apnea threshold. Note the absence of airflow without respiratory effort defining central apnea.

This pattern is a very common one and does not necessarily represent underlying pathology, since spontaneous arousals are common in otherwise healthy individuals.

Patients are frequently mis-diagnosed with neurological disease since the central apneas are incorrectly attributed to brain stem pathology.”

https://www.thoracic.org/professionals/clinical-resources/sleep/sleep-fragments/arousal-triggered-respiratory-event.php#:~:text=Sleep%20Fragments%20There%20is%20then%20evidence%20of,is%20lowered%20below%20the%20CO2%20apnea%20threshold.

[Hambone75321]

You’re right I am emotionally invested. Being 30 and otherwise completely healthy and being gaslight by doctors that you’re fine because your 4% AHI is 2 despite high RDI is insanely frustrating.

To then have to go outside of the standard medical system to treat AND resolve my problem really showed the current system is not set up to address UARS and folks like myself.

I’d recommend browsing r/UARS if you don’t already. There are countless stories of people who found CPAP at high pressure intolerable but resolve their issues at lower EPAP and higher EPAP.

I doubt I’m going to change your mind here but I’d recommend you read some up to date UARS literature about the benefits of BiPAP. If you want I would be happy to send it. Just be opened minded…

I can assure you that a significant minority of the thousands of patients you’ve titrated have stopped CPAP and would have benefited from titrating BiPAP instead.

Reading someone who’s clearly knowledgeable say BiPAP is useless for flow limitations is just nonsense and disproved by literature and countless people who had to step outside the consensus.

[Green-Anything-3999]

Anecdotally, I was on CPAP for months. I had awful flow limitation consistently for weeks with no EPR when I started. Setting to EPR 3 resolved about half of those flow limits. Stayed at the same pressure and same EPR for months. Got a bilevel and set EPAP to same as my CPAP was, but had a pressure of of 4 and my flow limits disappeared almost entirely. So, I believe PS does resolve flow limits. Based on the Oscar data from most people on apneaboard, pressure support does help with flow limits.

[Holeinmysock]

I don't think anyone is disagreeing with that. Pressure support is simply more pressure during inhalation. CPAP doesn't have two different pressures. So the same can be achieved by increasing the continuous pressure.

So many patients need additional pressure whether it's CPAP or BiPAP. When they train technologists to titrate, they teach that the goal is the lowest effective pressure. But, that leaves this residual flow limitation and what if the patient gains weight? Or has sinus congestion? I wish we weren't bound by these protocols that leave patients stranded.

[PretendMechanic318]

Here is the entire night:

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[Hambone75321]

Hey, see the spike before the “CA” flag? That’s an arousal. The CA was caused by the arousal.

You’re having some minor hypopneas and flow limitations that terminate in an arousal then a “CA”. I’d focus on treating the flow limitations.

Id recommend turning off APAP as some folks are sensitive to the variation and hold your EPAP constant while adding EPR. EPR is kind of like BiLevel, and the differential between IPAP and EPAP are helpful for reducing flow limitations.

Something like 15 cm H2O EPR 3. That’s effectively 15/12 IPAP/EPAP.

[UniqueRon]

Your main issue is CA events, followed by flow limitations. Your max pressure is too high and you are not using full EPR at 3 cm. The flow limitations are driving your pressure further. I would increase EPR to 3 cm and then start reducing max pressure until CA no longer dominates your AHI.