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RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - mdmarmd - 03-08-2019
MORE THAN YOU EVER WANTED TO KNOW ABOUT DAWN:
SnoringInOregon suggested using Dawn for cleaning P10:
I was interested in looking more closely at the ingredients in Dawn when I noted that at least two alcohol type-agents were included.
We have probably all encountered labels or user manuals exhorting us to never use alcohol containing products when cleaning a display panel.
Never use alcohol or ammonia-based cleaning fluid on your screen. We understand why many people use window cleaner on their monitors, many high-end flat screen computer monitors and HDTV sets have a nice glossy glass screen. The problem, however, is that both ammonia-based cleaners (e.g. window cleaners like Windex) and alcohol-based cleaners (diluted rubbing alcohol or specialty alcohol cleaners sold in electronics stores) can strip anti-reflective coatings off screens, cause clouding, or otherwise damage the screen. Even if you have a glossy glass screen, that screen is most likely coated with things that aren’t as durable and chemically resistant as glass. Don’t risk using using alcohol or ammonia-based cleaning fluids.
I am an outboard motor user, and many of us know that ethanol containing gasoline is probably damaging for our smaller gas engines. The first time I got servicing when my outboard started to run poorly, the service rep said the most likely culprit is ethanol. He said the ethanal causes the plastics in gaskets, fuel lines, etc. to deteriorate and often flaky, crumblies from the inner surface of the fuel line are found clogging the fuel system. In fact, he told me that Yamaha and Honda have said the use of ethanol containing gas will negate the warrantees on their outboards.
"Ethanol has inherent properties that can cause corrosion of metal parts, including carburetors, degradation of plastic and rubber components, harder starting, and reduced engine life," says Marv Klowak, global vice president of research and development for Briggs & Stratton, the largest manufacturer of small engines. "The higher the ethanol content, the more acute the effects."
So, I suspect that the most likely “harsh” component of Dawn is the “denatured alcohol”. This term usually refers to ethanol (as in alcoholic beverages) that is cut with an ingredient that makes it taste bad, gives severe symptoms, makes you blind or to die.
Of course we have no idea the percentage of these various ingredients and we aren’t material chemists, so this is just my hunch from what little I know. I did find a site that detailed the effect of denatured alcohol on various plastics: Crazing or stiffening seems to be the operative term. Also, we don’t know what kind of plastic is used in the vents.
However, assuming that by alcohol you either mean ethanol, which is the drinking kind of alcohol, or isopropanol, which is the alcohol in many cleaning products, then I can give you some advice based on common plastic types. Both are similar enough in their solvent properties that we can generalize.
Alcohol will damage some plastics, but not all. I will list my answers by the resin code, or "recycling symbol", found on most plastic items:
Poly(ethylene terephthalate), PET or PETE - PET is not very soluble in ethanol or isopropanol, but prolonged exposure may cause crazing or stiffening due to the dissolution of plasticizers.
High-Density polyethylene, HDPE - HDPE is resistant to most things.
Poly(vinyl chloride), PVC - PVC is not very soluble in ethanol or isopropanol, but prolonged exposure may cause crazing or stiffening.
Low-Density polyethylene, LDPE - LDPE is resistant to most things.
Polypropylene, PP - PP is resistant to most things.
Polystyrene PS - PS is not very soluble in ethanol or isopropanol, but prolonged exposure may cause crazing or stiffening.
This stands for "other", but the most common is polycarbonate, which is not very soluble in ethanol or isopropanol, but prolonged exposure may cause crazing or stiffening.
Rubber - most rubbers are probably resistant to alcohols, but prolonged exposure will cause loss of elasticity
I suspect that most of us replace cpap components before this ethanol related deterioration becomes clinically relevant.
As an aside, it is interesting that silicone is such a resilient material.
(https://www.shinetsusilicone-global.com/catalog/pdf/rubber_e.pdf)
Resistance to Oils, Solvents and Other Chemicals:
With regards to the effects of solvents and industrial chemicals on silicone rubber, the following data has been complied: Silicones are chemically inert and are attacked by very few common materials. Among them are concentrated sulphuric acid, hydrofluoric acid and, after long term exposure, high pressure steam. Like any elastomer, silicone has a tendency to physically absorb those materials with a solubility parameter near its own. This absorption may cause the rubber to swell and to soften slightly. In a few applications, this volume increase is advantageous. For example, a silicone rubber gasket exposed to certain solvents will swell to form a tighter seal. The change undergone by silicone rubber in contact with an absorbed solvent is primarily physical. After the solvent has completely evaporated, the silicone rubber will return to its original physical properties.
Heat and cold resistance:
Silicone rubber withstands high and low temperatures far better than organic rubbers. Silicone rubber can be used indefinitely at 1500C with almost no change in its properties. It withstands use even at 2000C for 10,000 hours or more, and some products can withstand heat of 3500C for short periods. Silicone rubbers are thus suitable as a material for rubber components used in high temperature environments. Silicone rubber also has excellent resistance to cold temperatures. The embrittlement point of typical organic rubbers is between -200 and -300Ct compared to -600 to -700C for silicone rubbers. Even at temperatures at which organic rubbers turn brittle, silicone rubber remains elastic. Some products withstand extremely low temperatures of -1000C and below.
Resistance to oils, solvents and other chemicals:
Silicone rubber has outstanding resistance to oil at high temperatures. Among common organic rubbers, nitrile rubber and chloroprene rubber have somewhat higher oil resistance at temperatures below 10000. but at higher temperatures silicone rubber is superior, Silicone rubber also has excellent resistance to solvents and other chemicals. It is essentially unaffected by polar organic compounds (aniline. alcohol, etc.) or dilute acids or bases, with the increase in volume due to swelling in the range of only silicone rubber does swell in non-polar organic compounds like benzene, toluene and gasoline but unlike most organic rubbers, jt does not decompose or dissolve, and will return to its former state when the solvent is removed.
Weatherability
Silicone rubbers have exceptional weatherability. Ozone created by corona discharge rapidly deteriorates most organic rubbers, but has almost no effect on silicone rubber. In addition, silicone rubber can be exposed to wind, rain and UV rays for long periods with virtually no change in its physical properties. contact with such chemicals.
Moisture and steam resistance
Silicone rubber can be immersed in water (cold water, warm water, boiling water) for long periods with water absorption of about 1%, and with virtually no effect on mechanical strength or electrical properties. Typically, under ordinary pressure, contact with steam causes almost no deterioration of silicone rubbers.
Physiologically inert
Living tissues are affected by contact with silicone rubber to a lesser degree than by exposure to other organic polymers. Silicone rubber is physiologically inert, and is thus used for baby bottle nipples and stoppers in medical applications
I actually suspect that if someone scientifically tested the silicone pillows for resilience and durability and other relevant physical characteristics, they could safely be used for much longer than the replacement schedule of 3 months would suggest (In fact, Resmed actually recommends 2 pillows/month).
The physical characteristics of silicone would seem to make it ideal to resist deformation, deterioration from heat, cold, moisture. Nor should it be susceptible to transmission of bacteria and grunge when kept reasonably clean. And being a medical application, I would expect the silicone Resmed uses is of very high quality.
Makes me wonder if these replacement recommendations are more based on economics than medical necessity. I have used my pillows for extended periods and suffered no apparent ill effects or increased leakage from deformation. Of course, this does not apply to other components such as tubing and frame which are made from plastics that probably deteriorate at a more rapid rate, or are not so easily cleaned or disinfected.
I wonder if these high replacement rates are accepted by the insurance carriers because they can convince people that the parts that contact the face, especially the nostrils and mouth must easily become irreversibly contaminated in a short period of times. (I also could understand it if the hard plastic rim of the P10 pillow began to deform and no longer stay in the frame, but I have not had a problem with it leaking or popping out.)
An example of short shelf life would be pharmaceuticals. While there are a few common meds like tetracycline, that deteriorate and even become toxic with time, many meds probably have a useful and safe shelf life far beyond the expiration date. For ten years I worked in refugee camps on the Thai Cambodian border. At one time we gathered expired medication sample packs to use in areas where there were no alternatives. I recall asking a pharmaceutical representative, if he thought the use of these out of date meds would be safe. He said that truthfully, many drugs are fine well beyond the expiration date as long as they aren’t exposed to higher temperatures which hastens chemical breakdown. Imagine how much is spent on refilling medications that probably are still good.
I AM NOT RECOMMENDING YOU EXCEDE THE EXPIRATION DATE OF YOUR MEDICATION!
I am merely pointing out that factors other than medical necessity may influence expiration dates and, in our case, replacement schedules.
Finally, looking at the other less probable culprits in Dawn:
Sodium Lauryl Sulfate Cleaning Agent Sodium Laureth Sulfate: SLS and SLES are surfactants which are the actual soaping ingredients found in all personal cleansing products including shampoos. Sulfates are the most common surfactant and offer a great balance of excellent cleaning properties without being harsh. All shampoos use some form of surfactant to capture oil and dirt and clean it off your hair.
Lauramine Oxide: is an amine oxide based nonionic surfactant. It is one of the most frequently-used surfactants of this type. Like other amine oxide based surfactants it isantimicrobisl, being effective against common bacteria such as S. aureus and E. coli.
Methylisothiazolinone, is a powerful synthetic biocide and preservative within the group of isothiazolinones, which is used in numerous personal care products and a wide range of industrial applications. It is a cytotoxin that may affect different types of cells
Phenoxyethanol: is used as a perfume fixative; an insect repellent; an antiseptic; a solvent for cellulose acetate, dyes, inks, and resins; a preservative for pharmaceuticals, cosmetics and lubricants; an anesthetic in fish aquaculture; and in organic synthesis.
Phenoxyethanol is a type of alcohol but from what I could find, I suspect it is likely used in a small amount and if so, making it less likely to significantly attack the integrety of the plastic in the frame.
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - mdmarmd - 03-08-2019
I would like to respond to some of the recent comments made by SnoringInOregon, Hydrangea, ghce, and Snoring Bear with respect to:
Role of proper maintenance as it relates to P10 vent obstruction
The publicly available information regarding and risk in using the P10
The argument that the lack of liability action substantiates a lack of risk
Snoring Bear writes:
It appears at the base of the problems associated with the Airfit P10 are issues of "proper maintenance".
First, I would like to report that I think I can now conclusively say that condensation alone is sufficient cause for P10 vents to obstruct. I have hinted of this in my earlier posts referring to reports that some people experienced obstruction with apparently new P10’s. But I had benn more focused on accounting for the delayed onset that I and some others experienced as well as my objective determination that dust deposits deep within the vents, that are resistant to normal modes of cleaning, seemed complicit in initiating this phenomenon. This combination of water and dirt provided an easy explanation of why there could be a delay, and then an abrupt onset of obstruction. It would also take in to consideration how individual maintenance and replacement patterns might account for the variability in how people do or don’t experience this problem.
But the other night I was using a P10 that I knew was new as well as had a backup very lightly used P10. I keep the backup because I know with fluctuations in ambient temperatures (which we are currently experiencing in the CA Bay Area, can provoke unexpected “rain out”. Some may view this as a completely avoidable condition, but I find that the variables such as changing room temperature through the night, the humidity and temperature settings can sometimes collude resulting in rain outs. I have had nights where I didn’t have a spare available, and it’s a real pain to try and blowout and then dry out the vents without completely arousing yourself from sleep and disrupting the whole night.
Anyway, I had had my settings around a temp of 80 and a humidity of 4 for awhile with no real problems. But on one morning I felt a bit more dried out and the following night I increased the humidity to 6. Well, that night I woke abruptly short of breath with all the symptoms I have come to equate with hypercapnia. I looked at the P10 tube and there was prominent condensation—the sort where little droplets were scattered around within the tube. Since I had a backup, I replace the whole P10 unit and went back to sleep. Shortly, I again woke symptomatic of hypercapnia and the second P10 also had rain out.
The next day I looked at both P10 vents under high magnification. This confirmed that one looked brand new and the other showed only the slightest hint of dust. So this could not be due to lack of maintenance.
I believe this strongly supports the conclusion that condensation is sufficient causation for vent obstruction, and dust accumulation while a contributing factor, is not a necessary causative factor. This argues against the view that poor maintenance is an adequate explanation for provoking these events:
[attachment=21462]
[attachment=21463]
My second point revolves around the question of what exactly is the publicly available information regarding the existence of this phenomenon, its frequency and its potential risk to health?
Snoring Bear, you made the comment:
…I had been cleaning those pieces daily since I was aware of the potential of adverse risks if I became complacent and/or lazy. I wasn't willing to take that risk.
I am interested to know exactly which “adverse risks” you are referring to? Since I haven’t really heard anyone say they have been informed of the risk of hypercapnia by their sleep doctor, or read about it in the product literature, what did you know and where did your information come from?
I set out to just prove that the vents were truly obstructed. I did not suspect that I would discover the high CO2 levels that my measurements indicated. And after determining this, I have still had the darnedest time finding out exactly what the clinical implications are.
Did anyone recall being told about the risk of vent obstruction or the resultant health risks of hypercapniaby by any health providers or equipment vendors? I recall OpalRose indicating that someone seemed to suggest she needed to monitor for decreased airflow.
I did find this from information from The National Institute for Occupational Safety and Health (NIOSH) of interest:[/url]
CO2 > 40,000 ppm: Exposure may lead to serious oxygen deprivation, resulting in permanent brain damage, coma and even death
This is for chronic exposure. But what about recurrent, intermittant, chronic exposure?
In medicine, informed consent means the patient has been given at least enough information to appreciate potential risks of a treatment to their health and make an informed risk/benefit decision on whether to subject themselves to the treatment. It also entails information regarding potential treatment emergent problems or side effects so that the patient will know when to seek attention.
In the forum threads, there are constant references to how rare or infrequent this problem must be because of apparent lack of public awareness. I find this bothersome, because what data is this conclusion drawn from? How reliable is the information it is derived from?
The post from Hydrangea is a perfect case in point. She wrote:
So now my mind is blown that I'd switched to a FFM because I mistakenly thought I could no longer nose-breathe at night, whereas the real problem was just that the P10s were suffocating me.
Did she bring this to the attention of her doctor?
Did she call Resmed (to give them the opportunity to say it’s not happening?)
No.
She attributed the problem to the design or perhaps her lack of adaptation, and switched to something else.
Hence, She never got on anyone’s database.
So we conclude…it clearly must be rare!
And the beat goes on….
I read on some CPAP retail site that the P10 garners over 30% market share for nasal pillows. That has to be many, many millions of people. But how many unreported cases like myself, or Hydrangea, or Hulk, or DaveResmedP10, or Scott1965 or OpineCone might there also be out there? People who don’t push back, and simply move on to another device.
How likely is it that a person will report or complain about a problem you don’t know exists? Is there any public information about this risk? And since we all know how difficult acclimating to a particular device can be, it is far easier for the doctor and the patient to just chalk it up to user error, or a “poor fit”. And, like Hulk or Hydrangea, you remain a "ghost" and just move on to something else.
It would be fascinating to have an epidemiologist actually do a study of current or past P10 users to see how many have ever experienced similar difficulties. And further, how many of these individuals reported concerns to their sleep doctor and were taken seriously.
For that matter, do a study and canvass sleep doctors to see how many believe this could even happen and how many appreciate the attendant risks?
The limited data I read in these posts suggest that people are told by their sleep doctors and even by Resmed, that this just doesn’t happen. As alluded to earlier, even, on this very site, made up, of well informed, well intentioned and help-oriented members, the majority of input in the past threads I have read, would dissuade people from believing this is happening or being concerned about this happening. It’s like Resmed must be sacrosanct and you must be messing up.
Without knowing a about potential risk, we don’t prioritize action. Life is all about balancing priorities and benefits vs. risk. If we know there is a particular risk, we look out for it, and we make the effort to mitigate the risk. But when there is really no known, clear risk only levels of discomfort, it is easy to see why one might, “…bec(o)me complacent and/or lazy..” in the cleaning of their equipment (Snoring Bear).
Furthermore, we are explicitly told in the user manual, Don’t Worry: “The vent may discolor over time and this is not a safety concern.”
Finally, I would like to address the argument that,
“If there were inherent safety issues plaguing this product, lord knows there would be countless million-dollar-lawsuits in the courts along with perhaps a huge class-action filing.”
With all due respect, this reflects a naïve understanding of what it takes to mount a successful suit against a massive corporation with a massive legal department. In the USA we are so litigious, that there is an illusion that you can sue anyone at the drop of a hat.
But, we only have to think of, cigarettes/Big Tobacco, Asbestos/myriad of industries, post-concussion encephalopathy/NFL, Talcum Powder/J&J, to realize how long and arduous the path can be for such litigation. No doubt many valid attempts never see the light of day.
Some of these involved obvious health risks that were still, truly hiding in plain sight.
A case in point, the current concerns about carbon monoxide leaking into Ford Explorer passenger cabins causing symptoms and sickness. This makes our present concerns truly seem like small potatoes! Your talking a potential health risk that can endanger your life and the lives of your family. Irrespective of the merits, I think this exemplifies the difficulties in moving a suit forward.
I think this has been going on for about three years. In this first article you can see how Ford’s lawyers try every which way to use technicalities to have the suit dismissed.
https://www.carcomplaints.com/news/2018/ford-explorer-carbon-monoxide-lawsuit.shtml
https://www.chicagotribune.com/classified/automotive/sc-auto-tips-0201-ford-explorer-dizziness-20180130-story.html
https://www.cbsnews.com/news/ford-explorer-safety-advocates-renew-recall-demand-carbon-monoxide-complaints/
https://www.autosafety.org/on-second-anniversary-of-nhtsa-investigation-into-carbon-monoxide-leaks-in-2011-2017-ford-explorers-center-for-auto-safety-renews-call-for-ford-recall-based-on-consumer-complaints-the-ford/
The general public is well informed about the risk of carbon monoxide poisoning. It's on their radar: It’s colorless,odorless, tasteless and lethal—people use it to kill themselves. It irreversably blocks the O2 receptors on hemoglobin, so essentrially your blood can no longer transport O2. So, it’s not a stretch to suspect this could be a problem when noxious odors fill your vehicle.
But ask people what the risk of breathing too much CO2 is. You expect there could be a risk of CO inhalation around a running vehicle. You don’t expect a natural gas, from your own breath, to create a health risk from within your FDA approved medical device. In fact, if you search on CO2 toxicity, a lot of articles are concerned about global warming causeing increased green house gases. The focus is on the consequences of longer, chronic, lower levels of hypercapnia.
Snoring Bear wrote:
“Luckily consumers have choices to use many different products”
But it’s not quite so simple, because an end user does not have adequate information to make an informed choice. Some, like myself, and others, love this P10 and, not knowing the risks, will persist in using it, determined to make it work.
[attachment=10712]
As ghce noted:
Its a bit of a minefield when it comes to keeping users safe as medical providers of the P10 are most likely the ones who advise users rather than ResMed itself. In my particular case my provider supplies just one mask a year on request.
Normally with medications they come to the end user with a list of side effects and contraindications. The point being with the P10 there is no mention of long term effects of CO2 due to not cleaning on a regular basis.
CO2 poisoning is a very serious thing which if unchecked for several years would undoubtedly have a very negative impact on the users health, cognition and longevity. None of this gets any mention from the manufacturer or providor....... and this from an FDA approved product, alarm bells should be going off somewhere.
I am no lawyer, but from day one in medical school, you are told to CYA regarding potential malpractice suites. The basic principle regarding informed consent is if it wasn’t written down that you provided it, it didn’t happen.
A legal test in negligence litigation involves the Reasonable-Person Standard:
The reasonable-person standard requires that a patient be told all of the material risks that would influence a reasonable person in determining whether to consent to the treatment…the reasonable-person standard has the advantage of encouraging physicians to discuss the proposed treatment with the patient more fully.
When a standard is based on reasonableness, it means that jurors are allowed to use their common sense to determine what should have been done. In an informed consent case, the jurors decide what they would have wanted to be told about the proposed treatment. This weights the standard toward disclosure, since each juror is more likely to add to the list of necessary information than to argue that another's concerns are unreasonable.
For those obsessives who might want to read a more rigorous discussion about a real malpractice case regarding a medical device company, I refer you to this article:
Understanding a Medical Device Manufacturer’s Broad Duty to Warn
A recent court decision in a case involving Intuitive Surgical serves as a useful reminder for medical device manufacturers to review their approach to product warnings.
https://www.mddionline.com/understanding-medical-device-manufacturer%E2%80%99s-broad-duty-warn
Washington State's highest court set off a bit of a firestorm recently when it ruled that medical device manufacturers must warn those who buy their products about related risks. The court's decision in [url=http://law.justia.com/cases/washington/supreme-court/2017/92210-1.html]Taylor v. Intuitive Surgical, Inc., seemed to undermine the customary view that a device manufacturer need only provide its warnings to the prescribing physician; the learned intermediary. A broader review of the law shows that the court may not have strayed too far from basic product liability concepts and provides a good opportunity for medical device manufacturers to review their approach to product warnings.
…medical devices are usually exempt from a strict liability analysis. Where a product has inherent dangers but still provides a public benefit, like prescription drugs or medical devices, the product may be termed "unavoidably unsafe." In many jurisdictions, a manufacturer may avoid strict liability for properly manufactured "unavoidably unsafe products" so long as the product is accompanied by "proper" warnings. The exemption from strict liability for unavoidably unsafe products is colloquially known as "comment k." The absence of strict liability for an unavoidably unsafe product often causes a court to place heightened scrutiny on the content and presentation of a medical device manufacturer's warning…
…A product manufacturer's duty is to direct its warning to the consumer or user of its product. However, a patient's access to a medical device is restricted by the patient's treating physician. A patient's treating physician is in the best position to evaluate the information provided by the manufacturer concerning the risks and benefits of its medical device, as well as available information from the scientific literature, and then weigh that information against the individual patient's condition and risk factors to determine whether treatment with a particular medical device is appropriate. The physician is also in the best position to communicate the risks and alternative treatments to the patient. For these reasons, nearly every jurisdiction in the United States recognizes that the patient's treating physician stands in as an intermediary between the medical device manufacturer and the patient; a "learned intermediary." Jurisdictions applying the learned intermediary doctrine require medical device manufacturers to warn prescribing physicians, not patients or consumers...
Conclusion: The various settings in which a medical device can be used to treat a patient present an assortment of challenges to a device manufacturer trying to satisfy its broad duty to warn. To evaluate the adequacy of existing warnings, or to develop warnings for a new device, a manufacturer should address these questions:
- In what way will this device impact patient treatment?
- Who will interact with this device before the device reaches the patient?
- What must be done to or with the device to prepare it for use in patient treatment?
- Who will use this device in treating the patient?
- What are the foreseeable risks associated with use of this device in patient treatment?
You cas ask yourself whether you feel the necessary information about this potential risk was given to you when your P10 was prescribed. It's kind of hard for a doctor to tell you about a risk they are not aware of.
If I was a plaintiff’s lawyer in a case regarding P10 and failure to warn, I would think certain elements would be crucial to look for during discovery:
In the development of the final product, did the manufacturer know there was a risk that condensation could obstruct the vents. If so, what design changes were made to mitigate this risk in the final product?
If this event occurred, with what frequency did it occur?
Did the manufacturer know what the greatest risk to the end user could be from such an event?
Were appropriate measurements and analysis done to determine, quantitatively the extent of the risk?
Post-marketing, did the manufacturer receive any input from doctors, DME or end users regarding possible concerns arising from this problem?
If so, what did the manufacturer do to mitigate future risk and inform prescribing doctors and end users regarding the possibility of this risk?
I suspect we have all probably scoffed at the huge warnings playing across the screen when a new medication is being marketed. Often a list of side effects scrolls by and end with…and may cause death.
This, like all the black box warnings and endless lists of side effects (most not proven to be caused by the drug) are there, more for legal, not medical reasons.
Because this would meet the standard that, “a reasonable person” had been informed of the attendant risks.
Thus, the manufacturer has fulfilled the non-delegable duties to patients to disseminate relevant information regarding the possible risks.
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - Hydrangea - 03-09-2019
(03-08-2019, 11:38 PM)mdmarmd Wrote: The post from Hydrangea is a perfect case in point. She wrote:
So now my mind is blown that I'd switched to a FFM because I mistakenly thought I could no longer nose-breathe at night, whereas the real problem was just that the P10s were suffocating me.
Did she bring this to the attention of her doctor?
Did she call Resmed (to give them the opportunity to say it’s not happening?)
No.
She attributed the problem to the design or perhaps her lack of adaptation, and switched to something else.
Hence, She never got on anyone’s database.
So we conclude…it clearly must be rare!
My sleep "doctor" was his own DME, and he was a sham. So I fired him (as my "doctor" and as my DME) less than 30 days after starting CPAP therapy.
I did tell my next DME's RT about my issues with the P10. They sent me a chinstrap, and recommended tape. My gut said no on both of those solutions.
I moved, and had to find a new DME, which required me to get a new doctor to write me a new prescription for CPAP supplies. I don't believe I told this new doctor about my P10 issues. But I did tell two RTs at this new DME about my P10 issues, and they both said 1) it's common and 2) it's due to not cleaning it often/well enough.
I did not call ResMed about this issue.
Regarding informed consent: The only info I've ever received for any mask I've used has been whatever I read in the user's manual. (The only exception to that is my newest DME screening me for a pacemaker, before letting me try the F20/F30 with the magnets.)
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - mdmarmd - 03-09-2019
Sorry Hydrangea,
I didn't intend to misrepresent your experience.
I really was presenting a hypothetical experience coming off your post.
I should have made that clear by prefacing with... suppose in Hydrangea's case, she had...
Doug
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - Hydrangea - 03-09-2019
(03-09-2019, 03:56 AM)mdmarmd Wrote: Sorry Hydrangea,
I didn't intend to misrepresent your experience.
I really was presenting a hypothetical experience coming off your post.
I should have made that clear by prefacing with... suppose in Hydrangea's case, she had...
Doug
Oh, no worries. I assumed as such. So I figured I'd clarify, so you could know.
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - ghce - 03-09-2019
I likewise have informed my provider by providing links to this thread.
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - mdmarmd - 03-09-2019
GOOD NEWS! FOR A CHANGE
So, I completed my latest, and hopefully last test for cleaning the P10—Using a WaterPik.
Now, I have discovered that vent obstruction can occur from water alone, apart from any dust deposits. I still believe that dust probably increases the risk for obstruction to occur, so I wanted to make a final attempt at removing this as a contributing factor.
Thus far I have tried soap and water brushings, high pressure flushing, faucet jet flushing and ultrasonic cleaning. Of these methods, the faucet jet flushing was what I had settled on to clean my P10. The high-pressure flushing was not practical and the ultrasonic cleaning, surprisingly, didn’t work.
So, I took the P10 that still remained quite dirty after the ultrasonic trial. I subjected it to warm soapy brushing and this actually proved to be fairly effective. I’d estimate it got it 70% clean—and these were very dirty vents. So maybe that’s good enough for many of you.
I had also remembered posts of people using their WaterPik to clean their vents. I had my doubts and wanted to see HiMag before and after pictures before I had confidence in this method. (I remember my wife asking about using a WaterPik for regular dental care some years ago. I pooh-poohed it as being probably a gimmick that didn’t really work. I didn’t think I could really accomplish what my twice daily, ambitious flossing did.) But after looking up WaterPick specs I saw that it attained 100 psi pressure and I thought, “Wow, that just might be pretty effective”.
So, I purchased a WaterPik Aquarious and did my testing today.
The WaterPik jet was powerful enough to send a spray out the opposite side of the vent. That seemed promising.
First, I retook magnified pictures of the P10 that had failed ultrasonic cleaning. Then I took pictures post soapy washing, and finally ater the WaterPik
[attachment=10729]
Inside Uncleaned.
[attachment=10730]
Inside Uncleaned HiMag
[attachment=10731]
Outside Uncleaned
[attachment=10732]
Outside Uncleaned HiMag
[attachment=10733]
Outside after Soap and Water Brushing
(to be continued)
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - mdmarmd - 03-09-2019
GOOD NEWS! FOR A CHANGE! (continued)
[attachment=10734]
Inside after WaterPik
[attachment=10735]
Inside after WaterPik HiMag
[attachment=10736]
Outside after WaterPik
[attachment=10737]
Outside after WaterPik HiMag
As you can see, the WaterPik restored the vent to what looks like pristine condition.
I therefore. conclude that warm soapy brushings may effectively clean most vents if done regularly. However, I wonder if, over time, there could be a build up of residual dust that becomes harder to remove. But, frequent enough replacement might obviate this as a problem.
However, for those willing to acquire a WaterPik like device, you can probably restore your vents to like-new condition with periodic WaterPik cleansing. No exposure to harsh cleaning materials would be needed.
So, it seems, now that we are informed of this risk, if we do regular cleaning, we can hopefully minimize exposure to hypercapnia.
However, this does not remove the possibility of obstruction purely from condensation. So, optimizing CPAP settings and the ambient environment to avoid rain out would still be very important considerations (Unfortunately, this might negate the full convenience of higher humidity settings and EPR.)
I had to sacrifice a frame in order to do HiMag pictures of the inside surface since the digital camera could not get close enough to the surface while the vent was situated in the frame.
Looking at the crosscut end of the vent material, it’s not surprising that water could create an airtight barrier. Visually, there seems to be no air gaps through the tightly compressed strands.
[attachment=10738]
I refer you back to the auditory recordings of the “opening snaps” in the beginning of this thread. The crescendo quality of the noise during inhalation clearly indicates how much effort it takes to inhale through wet vents, and no opening snaps can be heard during the expiratory phase, i.e. there’s no venting.
Opening Snaps from Obstructed P10 Vents
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - ghce - 03-09-2019
When I brush cleaned with detergent and a brand new soft tooth brush for about 5 to 10 minutes each side the vent came up looking new and very clean but 30 to 40 minutes is a very long time to scrub! The results looked much the same as your Pik clean, I might have to look into getting a pik if I wish to continue with the P10.
RE: EVIDENCE OF AIRFIT P10 VENT OBSTRUCTION CAUSING HYPERCAPNIA - vroomvroom - 03-10-2019
I was thinking of trying/getting back to the P10, but now I'm thinking maybe I should stick with the Brevida...