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RE: Help Calibrating APAP Pressure - TheWallofsleep - 06-14-2021
Thanks Sleeprider, and sheepless for the insight. It definitely complicates things to add PLM/RLS into greater consideration, but it is a direction nonetheless. As far as disturbances in Flow Rate caused from PLM, I think I do see what you are talking about. It appears as fairly dramatic disruptions, at somewhat set intervals, and fairly early in the night. These are not flagged as OA, CA, etc., the seem almost like 'pulses'. I see some of these, but also fairly long stretches where the flow rate is not very sinusoidal, or smooth wave-like, I was under the impression that a flow limit is essentially a measure of these deviations, and that is what directed me to the idea for ASV. As far as medication for PLM goes, I am on gabapentin, however on a very low dose, I have been on higher in the past but did not believe that it made much of a difference. I will make sure to do some research and to talk to my doctor about ropinirole or whatever options may be available. The most difficult task is establishing a trend. The TENS idea is very interesting and not something I have thought of, I will keep that in the back of my mind.
I apologize for posting a bunch of charts here, but I want to give an example of some second by second shots of my breathing patterns. These first samples from June 13 are what I believe is an example of RLS, I have one zoomed in close and one further out in order to better show the continuous pattern. The shots from June 7, I believe is a disruption of a different kind, or maybe its nothing at all, to me it seems like a completely different phenomenon and it follows no recognizable patter unlike the night of June 13th.
Thanks.
RE: Help Calibrating APAP Pressure - TheWallofsleep - 06-14-2021
Pt.II:
Here is more breath by breath detail of what I am talking about. I am not sure if this is normal or a sign of something else going on. There irregularities are pretty consistent throughout the night and on most nights.
RE: Help Calibrating APAP Pressure - SarcasticDave94 - 06-14-2021
Ok yeah if you wanted ASV to combat flow limits, it's not the ASV's greatest party trick. I'd probably say the VAuto for that type of duty. You have a wider range of pressure support for the FL.
RE: Help Calibrating APAP Pressure - sheepless - 06-14-2021
I would say that first 14 minute shot on june 13th is pretty clearly plm. my theory is that like chin tucking, plm induced flow limitations are not passive and as such can't be overcome by pap. plm induced flow limitations frequently result in runaway pressure with apap and very active pressure support with asv. that's why I'm leaning toward a preference for vauto despite having mixed apnea; i.e., because vauto allows me to stabilize both epap and ipap while asv requires setting max ps at least 5 cmw above min ps. that's disturbing to sleep with no commensurate benefit in resolving the flow limitations. again, these explanations are my assumptions (guesses) based on my experience with the condition and with resmed apap, vauto and asv machines, but I don't have an authoritative basis for them. however, even if my explanatory theories are wrong, the results and conclusions remain.
RE: Help Calibrating APAP Pressure - sheepless - 06-14-2021
I agree that the june 7 screenshots are flow limitations. they'll be more obvious if you change the x-axis scale to something like 80 to -80 or even 60 to -60 (right click the graph label). also drag the bottom of each graph box line up to compress the graphs to make room to include the flow limitation graph. your flow limit stats are decent but because of the way the resmed algorithms work, many flow limitations are never identified and flagged. as Dave said, vauto is a better bet for flow limitations than apap especially and probably asv as well.
RE: Help Calibrating APAP Pressure - sheepless - 06-14-2021
your minute ventilation and tidal volume look low to me. are 4.00 and 280 typical of your results? search online for a tidal volume calculator to determine what a normal range is for a male of your height and weight.
RE: Help Calibrating APAP Pressure - SarcasticDave94 - 06-14-2021
Tidal volume example for me, at 69 inches tall, I'd want "568 mL Tidal volume if target is 8 mL/kg, IBW 71 kg"..... Example only
For some reason I'm thinking about 600 for Vt, so the data from OSCAR may be ok.
Want to give me your height in inches and I'll plug it into a calculator. It'll pop out the same data in the quote but edited to use your height.
RE: Help Calibrating APAP Pressure - TheWallofsleep - 06-14-2021
(06-14-2021, 06:34 PM)sheepless Wrote: your minute ventilation and tidal volume look low to me. are 4.00 and 280 typical of your results? search online for a tidal volume calculator to determine what a normal range is for a male of your height and weight.
Those numbers do seem relatively close to what I normally have, however to be fair, I am not sure how much of a deviation is considered abnormal. Maybe a 10% deviation is not good, but I will attach the statistics for all of the data points I have for those ever since I have started using OSCAR. The only thing to keep in mind is that I had been titrating since early on, so I have not had the same min/max/EPR the entire time. Since Friday, June 4th, I have been consistently at min=10, max=15, and EPR=3.
RE: Help Calibrating APAP Pressure - TheWallofsleep - 06-14-2021
(06-14-2021, 07:46 PM)SarcasticDave94 Wrote: Tidal volume example for me, at 69 inches tall, I'd want "568 mL Tidal volume if target is 8 mL/kg, IBW 71 kg"..... Example only
For some reason I'm thinking about 600 for Vt, so the data from OSCAR may be ok.
Want to give me your height in inches and I'll plug it into a calculator. It'll pop out the same data in the quote but edited to use your height.
I do see why a VAuto is probably a better choice now that we are encroaching in on the problem. I am disregarding RLS at the moment, and focusing on the flow limitations.
If I am using a calculator online correctly, I get 459.1mL for Vt, which is not too far off from my 95% of 400, but again, I am not sure how much of a deviation is abnormal. I am 5'5", and 126lbs, or 57.1kg- in case the units are easier.
I will also attach some closeups of the flowrates adjusted according to what sheepless requested.
I think my breathing looks fairly sawtooth.
RE: Help Calibrating APAP Pressure - SarcasticDave94 - 06-15-2021
Here's the calculation using the same calculator I have my example from
372 mL
Tidal volume if target is 6 mL/kg, IBW 62 kg
496 mL
Tidal volume if target is 8 mL/kg, IBW 62 kg
So about 375-500 Vt AKA tidal volume
Compare both lines of mine, spreading my sample to show the same 2 lines...
426 mL
Tidal volume if target is 6 mL/kg, IBW 71 kg
568 mL
Tidal volume if target is 8 mL/kg, IBW 71 kg
So my Vt range is supposedly a bit more as I'm 4 inches taller
About 425-570 Vt for me except I'm not 71 kg but a bit over at 104.3 so my Vt would likely be even higher. I've also heard that since I was taller up until 4 years ago, major back problems, broken vertebrae and degenerative disc etc, I was about 6 foot tall about then, with my highest height being 6'2"in my twenties and early thirties. That shortening may have compacted my lungs, causing even more issues.