02-25-2019, 04:40 AM
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA
Well, I have been using the AirFit P10 since I got the AirSense 10 when I got on Medicare about 4 years ago. I still am using it and have been recommending it to my patients that have OSA. But I must say, now that I know these obstructions are not just an occasional inconvenience, but may present serious health risks, maybe I am creating a medical liability by recommending it.
Up until I got this hard data, I would just keep a backup P10 or my hybrid P10+ Nuance, especially during April and October when I am still using my 5th wheel at the lake. I had hoped, when I first posted my ALERT regarding possible re-breathing issues with Resmed Airfit P10, in December 2016 was that I would have verified if this was really a risk with capnography. Unfortunately, the software problems caused a two year delay in completing this project. If I had demonstrated significant hypercapnia, I had intended to file a MedWatch report with the FDA and let them do what is appropriate. As a physician, I am under no illusion that a company this big would take me seriously.
If anyone else that has experienced these blocked vents is so inclined I would encourage you to file a MedWatch:
MedWatch
With medical devices, as with reports about side effects with medications, you need to reach certain critical mass before the gears begin to move. A Lot of $ is at stake.
I hope to file my data in the next several weeks. I also will send my document to Kaiser Sleep Dept. here in San Jose.
I was restricted by the constraints of posting the report on this site, especially the short window for making edits. So it's kind of mangled. Also, the limits of the jpg files made the magnified photos more blurry than they really are.
I'm going to put together a PDF that will have the report with all the pictures, graphs, and charts so I can send it to Kaiser. If you'd like a copy when it's done, send me a PM.
As many have pointed out, apparently the majority of users are happy campers...
But perhaps a few of the ones who aren't, might have died??
I could see that if someone had a lethal event provoked by hypercapnia, it could easily be misconstrued as a cardio/pulmonary event, a CVA or a bad apnea event. If you have chronic health problems, have diabetes or are even overweight, there a lot of things a terminal event might be blamed on. There is a high association between OSA and other medical conditions.
Hulk is a perfect example of how things could be missed. Though I don't know if he actually experienced hypercapnia, he made a very simple, but accurate observation--over and over again--there is diminished or no expiratory flow through the vents!
As I mentioned earlier, you can prove this by simply holding up the dampened back of your hand near the vent. If it's not cool, there is no flow.
I too had had a terrible time adjusting to the CPAP, but my first symptoms of OSA were profound neuro-cognitive problems. I could talk with a patient I've seen for twenty years. And after 30 minutes, I'd turn around to make an appointment and not remember their name! So I knew I had no choice but to stick it out because, I told myself, "I need my brain!!". But my difficulties were from mouth breathing and profound xerostomia. My sleeping brain eventually said to itself, "keep your bloody mouth shut!" That's why, today, I can use a pillow.
In contrast, Hulk seemed much more distressed clinically with symptoms that didn't line up with the fact that his AHI had improved dramatically.
He posted:
"Over the period of a couple of weeks the fatigue increased to a point where, when I got up from a sleep period with the CPAP equipment, I was suffering fatigue like I have never experienced before and sometimes had a headache. It became dangerous to drive and I could not work. I would dispense with the CPAP equipment and go back to bed until lunchtime. I became concerned there was more going on than just acclimatisation?"
"I noted that I was waking up during the night with a higher respiration rate. Initially I thought it was just agro with the hose, mask head straps, noise etc. However, I also noted that there was venting out of the P10 Mast when breathing in but either very little or none, when breathing out! When I squeezed the tube on the exhale, it was very hard to breath out, upon releasing the tube it was easy to breath out. This lead me to concerns about re-breathing causing hypercapnia (carbon dioxide poisoning)."
He seemed to make every effort to dutifully follow everyone's advice. Yet, he described feeling the next day how I felt after 20 minutes of hypercapnia. It seemed he was even missing work. I don't think I could go to the office after the days of testing.
Yet the advice he received was not particularly helpful:
"...the advice received from Sleep Physicians and CPAP Technicians, getting acclimatised to CPAP is often a difficult process that everyone goes through and patience, tolerance and perseverance is needed."
"As promised, the feedback from the Sleep Technician and Physician in response to the question "is there an issue of re-breathing with the P10?":-
- "unlikely as it would be effecting so many people all over the world""
And he, at least had the benefit of this forum with very earnest and well informed members. Most would not be fortunate enough to have a support group.
Yet I believe only DaveResmed P10 really gave Hulk's concerns a full-throated defence.
Someone less fortunate might end up like the late Supreme Court Justice Antonio Scalia: Found with the hypercapiac equivalence of his, "unplugged CPAP" next to his bed.
So I guess all you P10 users will each have to decide for yourselves how to integrate these findings in your decision making.
Watch for symptoms. I didn't just feel tired or sleepy from the hypercapnia, I felt sick.
I for one, will be paying closer attention to signs of decreased venting. I will regularly "jet wash" my vents and keep them "microscopically" clean. (You can get a good USB microscope for about $35; search Amazon for "plugable digital usb microscope").
At least the element of dust can be reliably minimized. But Hulk's P10 was new as was DaveResmed P10's so there remains some risk from condensation alone it seems, unless these were "manufacturing variations", which Resmed said don't occur. (I didn't have the time to test just a wet P10.)
If yours is new, and failing to vent properly, replace it if you have insurance, but I would hold on to it as this might be the ones that the FDA would like to analyse.
That's about all the advice I can give you at this time.
I am still using mine "watchfully".
Doug
Up until I got this hard data, I would just keep a backup P10 or my hybrid P10+ Nuance, especially during April and October when I am still using my 5th wheel at the lake. I had hoped, when I first posted my ALERT regarding possible re-breathing issues with Resmed Airfit P10, in December 2016 was that I would have verified if this was really a risk with capnography. Unfortunately, the software problems caused a two year delay in completing this project. If I had demonstrated significant hypercapnia, I had intended to file a MedWatch report with the FDA and let them do what is appropriate. As a physician, I am under no illusion that a company this big would take me seriously.
If anyone else that has experienced these blocked vents is so inclined I would encourage you to file a MedWatch:
MedWatch
With medical devices, as with reports about side effects with medications, you need to reach certain critical mass before the gears begin to move. A Lot of $ is at stake.
I hope to file my data in the next several weeks. I also will send my document to Kaiser Sleep Dept. here in San Jose.
I was restricted by the constraints of posting the report on this site, especially the short window for making edits. So it's kind of mangled. Also, the limits of the jpg files made the magnified photos more blurry than they really are.
I'm going to put together a PDF that will have the report with all the pictures, graphs, and charts so I can send it to Kaiser. If you'd like a copy when it's done, send me a PM.
As many have pointed out, apparently the majority of users are happy campers...
But perhaps a few of the ones who aren't, might have died??
I could see that if someone had a lethal event provoked by hypercapnia, it could easily be misconstrued as a cardio/pulmonary event, a CVA or a bad apnea event. If you have chronic health problems, have diabetes or are even overweight, there a lot of things a terminal event might be blamed on. There is a high association between OSA and other medical conditions.
Hulk is a perfect example of how things could be missed. Though I don't know if he actually experienced hypercapnia, he made a very simple, but accurate observation--over and over again--there is diminished or no expiratory flow through the vents!
As I mentioned earlier, you can prove this by simply holding up the dampened back of your hand near the vent. If it's not cool, there is no flow.
I too had had a terrible time adjusting to the CPAP, but my first symptoms of OSA were profound neuro-cognitive problems. I could talk with a patient I've seen for twenty years. And after 30 minutes, I'd turn around to make an appointment and not remember their name! So I knew I had no choice but to stick it out because, I told myself, "I need my brain!!". But my difficulties were from mouth breathing and profound xerostomia. My sleeping brain eventually said to itself, "keep your bloody mouth shut!" That's why, today, I can use a pillow.
In contrast, Hulk seemed much more distressed clinically with symptoms that didn't line up with the fact that his AHI had improved dramatically.
He posted:
"Over the period of a couple of weeks the fatigue increased to a point where, when I got up from a sleep period with the CPAP equipment, I was suffering fatigue like I have never experienced before and sometimes had a headache. It became dangerous to drive and I could not work. I would dispense with the CPAP equipment and go back to bed until lunchtime. I became concerned there was more going on than just acclimatisation?"
"I noted that I was waking up during the night with a higher respiration rate. Initially I thought it was just agro with the hose, mask head straps, noise etc. However, I also noted that there was venting out of the P10 Mast when breathing in but either very little or none, when breathing out! When I squeezed the tube on the exhale, it was very hard to breath out, upon releasing the tube it was easy to breath out. This lead me to concerns about re-breathing causing hypercapnia (carbon dioxide poisoning)."
He seemed to make every effort to dutifully follow everyone's advice. Yet, he described feeling the next day how I felt after 20 minutes of hypercapnia. It seemed he was even missing work. I don't think I could go to the office after the days of testing.
Yet the advice he received was not particularly helpful:
"...the advice received from Sleep Physicians and CPAP Technicians, getting acclimatised to CPAP is often a difficult process that everyone goes through and patience, tolerance and perseverance is needed."
"As promised, the feedback from the Sleep Technician and Physician in response to the question "is there an issue of re-breathing with the P10?":-
- "unlikely as it would be effecting so many people all over the world""
And he, at least had the benefit of this forum with very earnest and well informed members. Most would not be fortunate enough to have a support group.
Yet I believe only DaveResmed P10 really gave Hulk's concerns a full-throated defence.
Someone less fortunate might end up like the late Supreme Court Justice Antonio Scalia: Found with the hypercapiac equivalence of his, "unplugged CPAP" next to his bed.
So I guess all you P10 users will each have to decide for yourselves how to integrate these findings in your decision making.
Watch for symptoms. I didn't just feel tired or sleepy from the hypercapnia, I felt sick.
I for one, will be paying closer attention to signs of decreased venting. I will regularly "jet wash" my vents and keep them "microscopically" clean. (You can get a good USB microscope for about $35; search Amazon for "plugable digital usb microscope").
At least the element of dust can be reliably minimized. But Hulk's P10 was new as was DaveResmed P10's so there remains some risk from condensation alone it seems, unless these were "manufacturing variations", which Resmed said don't occur. (I didn't have the time to test just a wet P10.)
If yours is new, and failing to vent properly, replace it if you have insurance, but I would hold on to it as this might be the ones that the FDA would like to analyse.
That's about all the advice I can give you at this time.
I am still using mine "watchfully".
Doug
