Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account


New Posts   Today's Posts

First Night on Therapy -- CA worries
#11
You may have another horrible night (or not) getting used to a new mask. Can you post up some sleepyhead graphs?


Using FlashAir W-03 SD card in machine. Access through wifi with FlashPAP or Sleep Master utilities.

I wanted to learn Binary so I enrolled in Binary 101. I seemed to have missed the first four courses. Big Grinnie

Post Reply Post Reply
#12
Thanks for the encouraging words, Alan! LOL!!

I'll post some SH graphs tomorrow.
Post Reply Post Reply
#13
FWIW, I had one or two CAs in my home study (AHI 55.7 untreated). I have probably twice the CAs than other events consistently under xPAP, however. Common sense says no CAs without xPAP and over 50% with xPAP somewhat points to the CAs not being a real issue, especially if the treated AHI is below 5 (mine is well below).

Some of that may be that while you have the mask on, the pressure from the blower is still circulating 02 (certainly at a lower rate than during inhale, or exhale) and that means that your CNS does not sense low 02 simply because it does not get as low as quick between breaths as it would without moving air. Moving air from the blower will increase aveolar respiration to a degree larger than inhaled air that is not moving, because the 02 molecules come in direct contact the aveoli more efficiently when the air is moving. Air that is not moving may be in your lungs, but it it is just sitting there static and not contacting the aveoli, the 02 does not get absorbed efficiently. Many of the sensors that are integral to the feedback loop that tells you its time to take another breath are actually directly in the aorta and other non-lung areas. Bottom line, it can take longer for the feedback loop to tell your system to inhale under those conditions, and longer pauses may be interpreted as CAs, even incorrectly.

But what is important is whether not taking a breath for a few seconds is actually contributing to an 02 sat that is low. If it is, then maybe the CAs are something to look into. But maybe a long pause between breaths is just normal every so often if it does not significantly contribute to a low 02 sat. This is where I would concentrate if I thought my CAs might actually be problematic.

But I have tweaked things to an average AHI of ~1.2 for the last couple of months, so I feel that's an acceptable number. The pressure can actually cause CAs, which is why when under APAP it is important to set a top limit to the range that helps prevent this (generally speaking, you can bring that number down until you start to bump up against that ceiling in most cases). In my case, lowering the top limit might lower CAs even a bit more, but I would indeed be bumping up against it (the APAP would be trying to deliver a higher pressure because it senses that I might need it) and I don't think my pressure limit is so high as to really be contributing to CAs all that much.

CAs are a little scary, because an OSA event is just a physical obstruction that you can fix with pressure, while the xPAP does not really have an effective therapy for CAs (or hypops) and a CA is not an external obstruction that can be dealt with; it is a function of the CNS directly. So it gets your attention. In most cases, however, for common OSA, a raise in CA events is caused by the pressure, and they are actually false positives for the most part.

The thing to really look into is whether your CAs might be something that would warrant a different type of machine, such as an ASV. A good PSG and a sleep doc that will parse that data and tell you yea or nay on that point is probably in order.
Post Reply Post Reply


#14
Tyrone -- wow! Thank you for your comprehensive and informative post. It really is amazing how much knowledge there is on this forum, as well as many generous people willing to share their insights with others new to CPAP therapy.

I've clearly got some homework to do on this subject. My current thought (assuming no dramatic deterioration in my therapy results over the next week or two) is to accumulate further data and then consult my doctor. In the meantime I'm going to continue to learn as much as I can.

Thanks,
Andy
Post Reply Post Reply
#15
And I think this is the place. Try the wiki. There is a lot of cached info here.
Post Reply Post Reply
#16
Mediocre results is better than no results. ;-)

FFor what it's worth, my doc had me set my first follow-up for two months after my consult with him reviewing my sleep study. That's two weeks to get my machine, two weeks for acclimation and 1 month actual therapy. After reading things here, the two weeks acclimation is making more and more sense. I'm still waiting to get my machine, so I've got a little ways to go yet, but I'm looking forward to pouring over the data.

Question for the smart people here the OP in this thread refered to CAs as "Closed Airway". I thought CA'S were Central Apneas. Is this the same thing? I had a bunch of CA'S show up on my titration which were not on my untreated study which worried me initially. After reading different threads here I'm glad to know it's normal.
Post Reply Post Reply


#17
(06-19-2015, 07:36 PM)AndyB Wrote: Thanks for the encouraging words, Alan! LOL!!

Keeping it real. Wink


Using FlashAir W-03 SD card in machine. Access through wifi with FlashPAP or Sleep Master utilities.

I wanted to learn Binary so I enrolled in Binary 101. I seemed to have missed the first four courses. Big Grinnie

Post Reply Post Reply
#18
@SleepyWabbit - the machines score CA if they interpret the breathing pause to be non-obstructive, so probably caused by something else. The two phrases usually used in place of CA are "CLEAR airway" or "central apnea".

A CA generally is detected by forcing a small pulse of air down your upper airway, and scores if there is no resistance.

If you did not breathe but were not obstructed, you probably "chose" not to breathe. Either you are awake-ish, or asleep-ish. Choosing not to breathe when asleep-ish is usually subconscious, either in dreaming (active mind) or a function of the central nervous system autonomous feedback loop (passive mind).

I have heard of some people actually having CA events because the brain sort of anticipates the trouble breathing and so breathes preemptively in a rapid then halting way. That continues until the brain settles the question of why it is not detecting the constant choking it used to, and begins to accept the "new normal."

QAL
Dedicated to QALity sleep.
You'll note I am listed as an Advisory Member. I am honored to be listed as such. See the fine print - Advisory Members as a group provide advice and suggestions to Apnea Board administrators and staff concerning Apnea Board operation and administrative policies. Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment.
Post Reply Post Reply
#19
(06-20-2015, 03:07 AM)SleepyWabbit Wrote: Question for the smart people here the OP in this thread refered to CAs as "Closed Airway". I thought CA'S were Central Apneas. Is this the same thing? I had a bunch of CA'S show up on my titration which were not on my untreated study which worried me initially. After reading different threads here I'm glad to know it's normal.

I don't claim to be in the "smart people" category but I did read a bit on it recently. CA is the usual acronym for central apnea, cessations in air flow occurring without respiratory effort. Your airway could either be open or closed when this happens. How a machine detects a CA is different with each brand. Resmed uses "forced oscillation technique". The definition of that is "a noninvasive method to measure the mechanical properties of the lung and airways during tidal breathing." BTW if I am way off base here, someone please correct me. I'm still learning too.

You can see it on the SH graph as a bunch of small oscillations with a flow rise.

[Image: CA.PNG]

Here is a shot of an OA you can see the same small oscillation but not an increase in flow.

[Image: HAOA.PNG]

With a bonus shot of hypopnea thrown in 30 seconds earlier. In that last graph you can see in that minute I hardly breathed. Makes me gasp for air just looking at it. Annoyed-and-disappointed



Using FlashAir W-03 SD card in machine. Access through wifi with FlashPAP or Sleep Master utilities.

I wanted to learn Binary so I enrolled in Binary 101. I seemed to have missed the first four courses. Big Grinnie

Post Reply Post Reply


#20
Andy, are you using EPR? For some people, that can aggravate CA. As an experiment it might be useful to turn it to 1 or 0 to see if it makes a difference for you. FWIW, CA events are usually much less disruptive to your sleep than OA, although we'd still like to keep it to a minimum.

See what minimizing EPR does for you, and with your OA and H apparently well controlled, I don't see any other changes for now.
Post Reply Post Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  My Experience So Far (and thoughts on changes to therapy) Esq. 18 311 5 minutes ago
Last Post: Esq.
  Returning To Therapy with Startling Results OldMarineOceanside 79 2,055 09-19-2017, 07:30 PM
Last Post: OldMarineOceanside
  First 3 weeks of therapy tjwoody 5 182 09-18-2017, 08:31 AM
Last Post: tjwoody
  When is sleep therapy no longer needed? rafimf 19 491 09-11-2017, 08:53 PM
Last Post: tmoody
  New to Apnea Therapy Esq. 19 2,021 08-18-2017, 05:08 AM
Last Post: Esq.
  [split] Take charge of your therapy - Heated tube Kathy123 8 424 08-13-2017, 08:30 PM
Last Post: Walla Walla
  [Treatment] Upper Airway Stimulation Therapy SideSleeper 2 195 07-27-2017, 11:51 PM
Last Post: SideSleeper

Forum Jump:

New Posts   Today's Posts




About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.

For any more information, please use our contact form.