Plmnb's Never Ending OSA Journey (Data)

[JoeyWallaby]

No, CPAP should reduce both occurrence and duration. If you didn't have a huge amount of flow limitations, you could just put the pressure up and your OAs and hypopneas would be significantly reduced. But because you have so much flow limitation, increasing pressure will also make flow limitation worse... which isn't ideal.

That's why bilevel has been suggested... to get rid of the flow limitations, which will probably reduce OAs and hypopneas straight away... and any remaining should be resolved with increased Min EPAP.

[Plmnb]

No, CPAP should reduce both occurrence and duration. If you didn't have a huge amount of flow limitations, you could just put the pressure up and your OAs and hypopneas would be significantly reduced. But because you have so much flow limitation, increasing pressure will also make flow limitation worse... which isn't ideal.

That's why bilevel has been suggested... to get rid of the flow limitations, which will probably reduce OAs and hypopneas straight away... and any remaining should be resolved with increased Min EPAP.

Just amazing information.  There is hope at the end of the tunnel!

Thank You!

[Sleeprider]

A couple clarifications.
Flow Rate is the volume of air per second in mL. It is similar to the flow rate in a hose, river or vent but we are measuring respired air. The flow rate chart has a zero line if you turn it on, and all the flow below that line is exhaled air and above the line is inspired air.If we crimp a hose or dam a river, it still flows, but the maximum flow rate is slowed. That is flow limitation, and the same thing happens with enlarged turbinates in your nose or a closure in the upper airway if the soft palate partially obstructs the airway...that smooth increase in flow flattens out at a lower rate of flow than normal.

Flow limitation usually refers to inspiratory flow limitation, and is measured as an index of 0 to 1 which can also be though of as percent. If flow limitation is 0.2, then a 20% flow limitation is present or peak inspiratory flow rate is 20% of the preceding 90 second average. If a flow limit of 1.0 is present, you are likely having an apnea or hypopnea.

RERA is respiratory event related arousal. Since we don't have EEG to measure sleep state, some CPAP machines monitor flow limitation and flow, then use an algorithm to determine if a period of increasing flow limitation is followed by in increase rate of flow which suggests an arousal or recovery breathing (Philips uses flow volume rather than a direct flow limitation). This is flagged as a RERA. The machine does not produce a time duration, so OSCAR shows a zero. One thought is that an arousal is simply an instantaneous event of a change in sleep state arising from your body's reaction to increased flow limitation which increases PaCO2 enough to trigger an increased respiratory rate, or simply arouses you to a lighter sleep stage to make you move or breathe. Apnea is a cessation of breathing for at least 10 seconds and we see these events flagged with a duration of 8 to as much as 90 seconds or more in unusual circumstances. Longer is worse. With regard to flow limitation and RERA the duration of flow limitation can be all night. It is extremely under-reported in Philips machines, and because it is a comparison of flow against a prior period of flow, a low flow limitation index is not necessarily an indication of a low flow limitation in cases where flow limitation is persistent. You have to manually look at the flow rate and identify flow limitation by the flattening of the peak inspiratory flow rate. You can have low AHI and high flow limitation and feel exhausted. RERA is only flagged for recovery or increased breathing rate and volume, and if that does not occur the arousal will not be detected by the CPAP RERA algorithm as it might by an EEG. That is the reason some of us on the forum look at the flow rate line for spikes of flow that might suggest arousal, whether there is a RERA flag or not.

Extensive flow limitation will suppress tidal volume, and may increase respiration rate (breaths per minute). The body seeks to maintain the same minute vent L/min, and a complex feedback system exists to ensure that happens. So when we see a respiration rate over 20 bpm, that is a flag to flow limitation as well. In my opinion, this is one more reason why the Resmed auto algorithms are superior to Philips. Flow limitation is measured on a breath by breath basis and the pressure responds to flow limits, while Philips simply measure flow and does not respond to flow limits, but instead will respond to decreased flow (if it is detected) as well as snores, apnea and hypopnea. This is the key to why Resmed pressure gets ahead of events in some people while Philips gets caught flat.

[Plmnb]

Thank you for the clarifications Sleeprider.

(So ResMed is a Phillips product?)

[Sleeprider]

Thank you for the clarifications Sleeprider.

(So ResMed is a Phillips product?)

Resmed and Philips are two different companies.  Resmed grew out of the development of the old Sullivan CPAP (looked like a vacuum cleaner) and was based in Australia but is now in California.  Philips Electronics acquired Respironics some years back and became Philips Respironics headquartered right here in Murrysville, PA. Philips is a huge diverse corporation. Look them up on Wkipedia.

[Plmnb]

Yikes, what a struggle to get to this point!  Thank you everyone!

Here are the results of part one of the soft cervical collar experiment.  So what do these results depict?  Tonight is part two of the experiment.  As instructed I will be changing the setting from 3 to 0.


[attachment=18101]

(This was second night with the new mask)

[snorybob]

As mentioned in post #2, you forgot to take out the calendar( click triangle in the date) & the pie chart( file -preferences-appearance-uncheck pie chart- click ok bottom right).


This will give more info. on your profile for the advisors.   


                             sb.

[Plmnb]

As mentioned in post #2, you forgot to take out the calendar( click triangle in the date) & the pie chart( file -preferences-appearance-uncheck pie chart- click ok bottom right).


This will give more info. on your profile for the advisors.   


                             sb.

Oh dear, sorry.  I wondered about that...The information on the left seemed like it would be an additional help.  In the future i will delete those portions.  Thank you for your guidance.

Plmnb

[Sleeprider]

What setting are you changing from 3 to 0, EPR? I think you need as much pressure support as you can get. I can't explain why you are having episodes of severe flow limits, snores, apnea and hypopnea while using the soft collar. Do you feel you are getting support at the back of the jaw or chin and no pressure on the front of the throat?

[Gideon]

I see the difference between EPR of 0 and 3 as evidence for the need for a BiLevel (VAuto), nothing more. No question about EPR of 3 being a better therapy.