CompSA, Hypoventilation, PLMs, Bradycardia and Hypotension?

Muffy wrote:It seems pretty clear that the respiratory instability (read CPAP Flow) in this area is a direct result of the PLMs (read L Leg-- R Leg is blown)

Hi Muffy, Good to see the ASV data, thanks. I think it is interesting to see how regularly my PLMs occur, as well as the fluctuations you point out in my CPAP flow waveform (nice work Sherlock Holmes ) Plenty to ponder! (e.g. SpO2 oscillates with respiration wax/wane but EtCO2 does not.) Cheers,

blizzardboy wrote:SpO2 oscillates with respiration wax/wane but EtCO2 does not.

It would if the ETCO2 data recording interval was better than it is. Rather than once every 3 seconds, it should be like 4/second.

Muffy

Muffy wrote:It seems pretty clear that the respiratory instability (read CPAP Flow) in this area is a direct result of the PLMs

Hi Muffy, Do you think that my "stutters" are associated with PLMs? Is this stuttering something you seen in PSG data before? Cheers,

Hi All, Some observations from last night (http://users.adam.com.au/sixsome/ASV/0610/060810/).
Last night I decided to go to sleep without the bed wedge (for old time sakes ). I woke at 0110 due to a gagging feeling in my throat. Suspecting reflux, I went back onto the wedge for the rest of the night. I did not wake again due to this gagging feeling but awoke in the morning with a burning feeling in my throat, and I am grumpy and irritable.

Another thing happened in the night. I had an epiphany of sorts. The conclusion of my various thoughts was that I have worked hard all my life, payed a heap of taxes to date, am raising a young family, have many years of work to contribute to society, and believe that I should be getting all the tests available (within reason) to work out what is going on with my body during sleep. Do I really have to be knocking on death's door before I am granted access to tests? I feel it is completely reasonable to have my lungs, heart and throat/stomach tested to ensure that this bread winner is in good order. Surely that is a reasonable request. I think so. In my slumber I named this thought: "The Golden Step - A Significant Realisation in the Mind of Blizzardboy." Thank you for listening. Cheers,

blizzardboy wrote:Do you think that my "stutters" are associated with PLMs?

No, that is a breath-by-breath phenomenon that appears totally unrelated.

blizzardboy wrote:Is this stuttering something you seen in PSG data before?

LOL! It seems like there's always something trying to alter the waveform (although being a somewhat "closed" system, a CPAP waveform can usually be a little easier to control than a nasal pressure cannula system).

By-the-by, it doesn't look as though they took the CPAP Pressure reading directly from the machine using the ResMed interface ("ResControl") since the pressure reading stays at "0" all night.

That said, that signal may still be able to be manipulated to generate the pressure readings.

Muffy

Muffy wrote:By-the-by, I don't believe your pressure waveform was pulled directly from the machine (using the interface, called "ResControl"). It would seem if they had, that would also have pulled the CPAP Pressure off it as well, but that just stays at "0" all night.

Hi Muffy, I've just downloaded asv_CPAP.rec from my RapidShare webpage and it displays the shape of the pressure waveform OK in Polyman if the scale is set to 0.2-0.5 cmH2O. I just right-clicked on the left pane and selected "Scale...->to fit pane". Cheers,

Now we'll just have to do a manual calibration:





Muffy

Muffy wrote:Now we'll just have to do a manual calibration:

The Sleep Centre recommended I use EEP=8 and PS=3->8, so I am supposing that these are the settings used in the last part of the titration. How do you reckon they measure up?

p.s. just read the PSG report and EEP is switched between 7 and 8 cmH2O throughout the titration.

By report, it looks like EPAP is 7 or 8 cmH2O, and IPAPmin 10 or 16 cmH2O, and this data must have been manually entered into the PSG software.

Muffy

blizzardboy wrote:

Muffy wrote:Now we'll just have to do a manual calibration:

The Sleep Centre recommended I use EEP=8 and PS=3->8, so I am supposing that these are the settings used in the last part of the titration. How do you reckon they measure up?

p.s. just read the PSG report and EEP is switched between 7 and 8 cmH2O throughout the titration.

NFS.

Muffy

Anyway...

Using the "MS Paint" Method of Calibration:



Muffy

Although this is an isolated example, it should really give pause to the ASV Will Fix The Planet crowd:



Here we have the development of a flow limitation as evidenced by the flattening of the flow waveform in CPAP Flow and increased snoring activity in dB. Although Adapt SV is "volume-oriented" (establishing a VE-based Target Ventilation) it nonetheless senses a problem and launches an IPAP-based attack. However, the attack proves ineffective as not only the flow limitation gets progressively worse, but totally fails as bb goes to arousal (EMG increases and the EEG amplitude decreases as sleep lightens from N3 to N2).

Muffy

Muffy wrote:Although this is an isolated example, it should really give pause to the ASV Will Fix The Planet crowd:

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Here we have the development of a flow limitation as evidenced by the flattening of the flow waveform in CPAP Flow and increased snoring activity in dB. Although Adapt SV is "volume-oriented" (establishing a VE-based Target Ventilation) it nonetheless senses a problem and launches an IPAP-based attack. However, the attack proves ineffective as not only the flow limitation gets progressively worse, but totally fails as bb goes to arousal (EMG increases and the EEG amplitude decreases as sleep lightens from N3 to N2).

Nice example, Muffy. Drives home the point of making sure ASV base pressure adequately addresses the obstructive component, leaving IPAP fluctuations to address central breathing.

As an isolated incident above, that's not such a big deal. However, tasking traditional ASV (w/ fixed base pressure) to automatically address a significant outstanding obstructive component is not recommended by manufacturers.

Muffy wrote:

jnk wrote:

blizzardboy wrote: . . . I am getting considerable arousals from PLMs, right? i.e. treat the PLMs=>sleep better. . . .

Birgit Högl, M.D., in [i]Journal of Clinical Sleep Medicine,[/i] Vol. 3, No. 1, 2007 wrote:"It is well established that PLMS are associated with microarousals and autonomic activation and therefore associated with an alteration in sleep structure. Whereas older concepts assumed that PLMS caused those arousals, more recent studies revealed, that PLMS and arousals are associated in another, more complex and non-unidirectional manner: Arousal equivalents, e.g. delta waves, heart rate increases or other changes in cerebral and autonomic activity can herald PLMS. In the most recent scoring criteria for periodic leg movements (PLM), this has been taken into account and a PLM with an arousal can be scored even if the arousal precedes the onset of a PLM."--http://www.aasmnet.org/JCSM/Articles/030102.pdf

They reported that PLMS are associated with cardiac acceleration, even in the absence of arousal.

Coarsely, I think that appears to be true in bb's case, but we need to run a different routine to analyze that.

Muffy

Unfortunately, I cannot get the Heart Rate Variability program to analyze bb's ECG signal (it needs to calculate the r-r intervals, but can't)(there's a dos-based routine, I think the command was format c: or something like that, I'll give it a try later) so that analysis will have to wait.

Muffy

Muffy wrote:...I think the command was format c: or something like that...

Well that didn't work out quite as well as I had hoped...

Muffy