Most Unusual Night

[wolson]

I have a question on the flow rate chart on wolson's 3rd chart. each of the two CAs in the middle of the time period has what looks like a small breath in the middle. Is that PRs pressure pulse to determine if the airway is clear or obstructed?

Best Regards,

PaytonA

The answer is no: the machine does not have this capability.

The visit to the pulmonologist was very interesting! For years, based on chest xrays, i was told I have moderate COPD. Well that diagnosis was shattered after a full PFT. I don't have COPD. While I have some hyperflation of the lungs, there is no emphysema and no evidence of bronchial obstruction! Huh? My apneas are considered extrathoracic!

So what is causing COPD like symptoms? My doctors nor I know the answer to that question. So I am under going a groups of tests mainly focusing on my vascular system.

It seems I have both an aneurism and a partial blockage in the descending aorta. Both were picked up on a CT scan. I had an angiogram a few years ago that failed to pick up on this (I was having the same symptoms then.) So is that creating the physical symptoms of COPD?

Now the question is what to do about it and will that cure the COPD symptoms? What effect will this have on my apneas?

[PaytonA]

I have a question on the flow rate chart on wolson's 3rd chart. each of the two CAs in the middle of the time period has what looks like a small breath in the middle. Is that PRs pressure pulse to determine if the airway is clear or obstructed?

Best Regards,

PaytonA

The answer is no: the machine does not have this capability.

Walt,

Your machine looks like an auto machine running in auto mode and it looks like it is a Philips Respironics. The answer to your docs answer is that your machine does discriminate between CAs and OAs I think and it does so by measuring the return on a pressure pulse that it sends out.

Best Regards,

PaytonA

[wolson]

I have a question on the flow rate chart on wolson's 3rd chart. each of the two CAs in the middle of the time period has what looks like a small breath in the middle. Is that PRs pressure pulse to determine if the airway is clear or obstructed?

Best Regards,

PaytonA

The answer is no: the machine does not have this capability.

Walt,

Your machine looks like an auto machine running in auto mode and it looks like it is a Philips Respironics. The answer to your docs answer is that your machine does discriminate between CAs and OAs I think and it does so by measuring the return on a pressure pulse that it sends out.

Best Regards,

PaytonA

Payton,

I am can only report what he said. I don't if that is the way the machine's algorithm distinguishes between a CA an a OSA. There is clearly a lot of "magic" going on in its algorithms. Unfortunately, the algorithms, as far as I know, are not published and probably regarded as trade secrets. However, since FDA had to approve the machine for medical use, the algorithms are probably protected by patents and those are discoverable. ( Something for a " round tuit.")

Whether or not the PRS1 has the servo response required is questionable as I do not see this in regions where I have long period hypopneas. I also do not see this in all of the CA's. Perhaps later, I will clip some wave forms to show this.

Walt

[Sleeprider]

Although the PRS1 Auto does not treat CA with servo ventilation pressure support, it does indeed send a rapid 2 cm pressure pulse to detect an open or closed airway. A compliant airway, indicated by the small inhale/exhale response to that pressure pulse indicates a clear airway apnea, or CA, which was flagged. A pressure pulse with no response is an OA. The pressure pulse just bounces off an obstructed airway kind of like sonar. Anyway, this is how PRS1 differentiates between the events.

[richb]

The machine also does not use the pressure pulses to test for Hypopneas or periodic breathing. Respiration is still taking place albeit at a lower level during the hypopneas.

RichB

[GPSMapNut]

With PR machines, there is no need to guess if it was a pressure pulse or not. Look at report in Encore Pro and you will see the PP ( pressure pulses) clearly marked as such.

[wolson]

Although the PRS1 Auto does not treat CA with servo ventilation pressure support, it does indeed send a rapid 2 cm pressure pulse to detect an open or closed airway. A compliant airway, indicated by the small inhale/exhale response to that pressure pulse indicates a clear airway apnea, or CA, which was flagged. A pressure pulse with no response is an OA. The pressure pulse just bounces off an obstructed airway kind of like sonar. Anyway, this is how PRS1 differentiates between the events.

I have considerable evidence to show that this is probably not true. Please examine the following clips of various CA's:



While quite a few CA's do have that small pulse and rebound, quite a few do not as indicated by the figure. Also look at the trace send from the bottom. You will see the pulse and rebound signature marked by a hypopnea. I have a lot of these pulse and rebounds that are not flagged for apneas.

Thus, I due not believe that the PRS1 is creating them as confirmed by my pulmonologist

As always, I am open to second opinions.

Walt

[richb]

Although the PRS1 Auto does not treat CA with servo ventilation pressure support, it does indeed send a rapid 2 cm pressure pulse to detect an open or closed airway. A compliant airway, indicated by the small inhale/exhale response to that pressure pulse indicates a clear airway apnea, or CA, which was flagged. A pressure pulse with no response is an OA. The pressure pulse just bounces off an obstructed airway kind of like sonar. Anyway, this is how PRS1 differentiates between the events.

I have considerable evidence to show that this is probably not true. Please examine the following clips of various CA's:



While quite a few CA's do have that small pulse and rebound, quite a few do not as indicated by the figure. Also look at the trace send from the bottom. You will see the pulse and rebound signature marked by a hypopnea. I have a lot of these pulse and rebounds that are not flagged for apneas.

Thus, I due not believe that the PRS1 is creating them as confirmed by my pulmonologist

As always, I am open to second opinions.

Walt

Does this machine have a backup rate set?
RichB

[wolson]

Does this machine have a backup rate set?
RichB

Good question: what is the backup rate and what does it do? I don't know how to answer this question.

Walt

[PoolQ]

I am pretty sure that they do indeed use pulses because not only do they say they do, but I have looked at their patents and they disclose that they do, they both (Resmed and PR) use different methods for patent reasons I assume.

It has to do with impedance of the airway. You have a tube with a relatively large plastic bottle on the end and right before the bottle you have a valve that can be open or shut. You can send a pressure pulse down the tube and measure the pressure changes. If the valve is closed the pressure will increase more quickly and higher then if the valve is open, because air is compressible. This is how they both test for OA verses CA.

As for COPD. Both my Doctor and my pulmonologist said that I clearly do not have COPD before the testing. After the testing they said I have unspecified COPD, they have no idea what it really is but "may" be COPD. They prescribed me the first level of COPD meds and bingo I could now sleep. Is it COPD? I have no idea and neither do they really. Am I just way more sensitive than most? Could be. Whatever the case, the meds are working and I am comfortable enough to sleep really well.

Edited for reality