[Diagnosis] Round 2 Sleep Test

[pearlpearl]

On the April 14th download your corrected AHI is 0.0.  The obstructive events are actually centrals misread by FOT.  All the centrals are post-arousal or sleep onset therefore should not be counted nor treated.  While some breaths might have the appearance of flow limitation they are probably a result of cardioballistic contamination.  ASV will not help and perhaps even hurt because the "centrals" are normal phenomena and need to be left alone.  The recommendation of mandibular advancement is irresponsible.

Your sleep quality is horrible.
Horrible horrible horrible.

Send me my buck.

Rubicon, please help to support your above statement - corrected AHI is 0.0 on April 14.  Kindly support with a snapshot of the graph and explain please.  I know you have something up your sleeve.  Your observation and knowledge will be good to be shared.  

At the meantime, let me recall April 14th night 

[pearlpearl]

I wouldn't expect you to feel significantly better with this machine. Your two sleep studies showed untreated AHI of 13 and 21 and both had at least some central apnea (can't see original study anymore but I see comments saying it was predominantly central/mixed). Your results on PAP have not been much better usually ranging from 10-20 (although mostly central on PAP compared to mostly obstructive without). The attempted treatment is an obvious failure and that is how your doctor should be treating it as well, not turning a blind eye to central apnea in two sleep studies and every night of PAP data...

I am not opposed to you quitting since the reason you are on cpap is a bit odd anyways but if you do end up noticing you are sleeping worse than at least you know what you need to do to try and get adequate treatment (ASV). The option that would make the most sense is to convince doctor to try and treat your central apnea or to find another doctor that will. A titration study would prove to them that this machine doesn't treat your central apnea if that is what it takes to convince them. Other option is to find a way to purchase an ASV yourself, unfortunately they are overpriced now thanks to CPAP shortage.

Edit: Oh and I can't remember your age or if it was mentioned but central apnea is most commonly associated with medications (like opioids), medical conditions or older age. If young and there are no reasonable causes then looking into it with a doctor (MRI etc) might be worthwhile.

Thanks Geer1 for your advice.  I am in my early 50s.  I don't think i will be assigned a ASV after consulted 3 doctors.  At least not for now.  My 2 sleep tests result from a Moderate to ->Mild.  The doctors do not believe i need a ASV and my guess is they do not want to be held responsible in an event i have any underlying medical condition especially during the current Covid19 episode still evolving.  There is no titration study for ASV machine either.  In summary, this machine is banned in Singapore for home use unless one secretly smuggle in without a doctor's prescription.

I do have a mandibular device but it was painful on me after a while use.  I also feel my jaws will end up with structure problem if for long term use.  But conclusion it didn't really work on me.  I did an experiment, wore it with APAP, and shut my mouth with the sticker. The apneas were still there! I also has a tennis bag to sleep on my side, cervical collar, mouth sticker hahaha whatever you name probably i have all those "gadgets" hahaha

I am tired with this apnea treatment. 

[Rubicon]

"Glad to help!  Rainbows and unicorns!

But we have a ton of stuff to review.

[pearlpearl]

"Glad to help!  Rainbows and unicorns!

But we have a ton of stuff to review.

[pearlpearl]

I am learning to read the graphs.  If anyone has the time please help.  Thanks!

Flow Limitation - What does these small little "blocks" represent?

Flow Rate - It means i slept and woke, slept and woke repeatedly.  Am i correct?

[Geer1]

Flow limitations can be seen here. The flow limitation graph gives you an idea of the amount of flow limitation present (higher value means more restriction which shows up as a flatter breath on flow rate chart).

http://www.apneaboard.com/wiki/index.php...limitation

Flow rate is the rate of air flow in/out. Positive flow rate is an inhalation. Negative flow rate is an exhalation. Flow rate doesn't tell you when you are awake or asleep other than when you can interpret examples of an arousal. In that example you posted there appears to be an arousal just after 00:54:00, can tell this because of the few weird shaped breaths high amplitude breaths (arousal breathing). Your breathing then starts to normalize (become more consistent) until the central apnea at 00:55:30 which is most likely a sleep transition central apnea. You go through a period of sleep transition central apnea, paused breaths (00:57:00, see how it looks similar to central apnea but not as long, apnea has to be 10 seconds long) and some recovery breaths between apnea (00:59:45) then this period of apnea/recovery breaths transitions into periodic breathing after 1:00:45 (same sort of pattern of increasing then decreasing flow rate but less severe because your breathing is stabilizing). This example shows how it took you ~ 5 minutes for breathing to stabilize after an arousal.

[pearlpearl]

Thanks Geer1 for your time but please be patience with me.  I think i am going to annoy you till you give up hope on me! hahaha  

I still don't get what does the flow limitation tell a "story" to my breathing.  How exactly a normal person flow limitation looks like? 

Let me focus on the flow rate graph.  Were those breathing that i circle in Red were normal breathing without arousal or pause or whatever abnormality?
   

[Geer1]

You seem to be having trouble understanding flow rate. Flow rate is the speed of air being inhaled or exhaled. Take a normal breath in, lets say that the flow rate was + 15. Now take a hard fast breath in like you are trying to catch your breath, that is probably something like + 30. Take a normal breath out, that is probably around -15. Take a hard breath out (like trying to blow out a candle) and it is probably -30. Hold your breath and flow rate is 0. The flow rate changes from positive (inhale) to negative (exhale) on every breath. Normal breathing has a gradual transition from exhale to inhale, a rounded peak inhalation, a faster transition to max exhale and then slowly starts changing back to another inhalation. 

Flow limitation is an index from 0 to 1. The higher the value the more restricted your inhalation was. A normal breath has no flow limitation. A flow limited breath has a lower flow rate (because it is restricted) and a flatter top (sometimes even convex appearance). In order to breath in the same amount of air you have to take a longer breath. Find a straw and breath in normally and then try breathing in through the straw. Breathing through a straw creates flow limitation and makes it harder to breath in. 

The instances you circled are 0 flow rate and more than 10 seconds which means they are apnea. They are followed by CA flags indicating they are central apnea (machine has a way to differentiate central vs obstructive apnea). There is almost no normal breathing in that example but the closest is after 01:01:30 when your breathing starts to stabilize. The breathing where green line is paused breathing (looks similar to an apnea but shorter length and because it is under 10 seconds is not an apnea). 

I modified this image to give an idea of what normal breathing looks like, flow limited breathing and then an apnea. You should be able to see how the breath size declines as flow limitation increases and how if flow rate stops it can be an apnea.

   

If you are having trouble understanding this still maybe try wearing CPAP and taking some normal breaths, holding breath, taking shallow breaths, taking deep breaths etc in a way you can remember and then look at your CPAP data to see how it compares to how you were breathing.