Very High Uncontrolled Pressure ResMed Airsense

[ejbpesca]

If loss of seal at the water tank causes the top end 20cm pressure to occur. I wonder how anyone could use such pressure if it inflates the mask, your cheeks and lungs as I experienced with this high pressure issue. At that pressure, good mask, good tube, I could not get the mask to seal due to too high pressure in test mode. I wonder now if mask test mode sent the machine into producing more than 20 cm. Maybe it takes a special mask in order to use 20cm pressure.

[ejbpesca]

NEVER ACCEPT A LESSER MACHINE
Having used a Resmed (check spelling very carefully--off brands use similar names),
you need the same make/model, or a newer version of exactly the same thing.
Going from a Resmed to a Luna would be equivalent to trading in a Lincoln for a Yugo.
Don't let them scam you.

Just got ball rolling on a new DME (local this time) who claims they have AirSense 10 and 11 in stock. Hope to give them a visit soon and have my new machine in a month or so.

[palerider]

So, what you had, based on Robysue's suggestion and your fix was not a high pressure problem,rather you had a high AIR FLOW problem which made a lot of noise, and made you think that there was a lot of high pressure, but if you had a massive leak at the humidifier, then you'd actually have LOWER pressure at the mask, if you think about it.

It's often very hard to separate these perceptions from reality, and end up going off in the wrong direction. That's why I was suggesting measuring the pressure with a tall glass of water, (or a pitcher). 20cmH2O is only about 8 inches.

[palerider]

If loss of seal at the water tank causes the top end 20cm pressure to occur.

That's not how the machine responds to large leaks. The machine will ramp up airflow to try and achieve the set pressure. If there's a huge leak, you're not going to get your desired pressure at the mask.

In cases of really severe leaks, the machines actually *LOWER* pressure to try and get masks to seal again. I've got a chart around here showing that exact thing.

[stevenal]

Now to deal with one of my old spare machines, a Philips recall. It is over 5 years service so Philips offers no replacement, but they may offer some payment to return it to a DME. My new local DME, 2 miles from me, is a place it can be taken. Waiting on the fax from clinic to DME, to get all in place.

Thanks so much to all for the advice here to help me hunt down and solve the high pressure problem!

Y'all are the best!

Check the recall thread. They are replacing older units, you just need to jump through all the hoops and reject their payoff offer.

[SleepGeek]

I wonder now if mask test mode sent the machine into producing more than 20 cm.

It's often very hard to separate these perceptions from reality, and end up going off in the wrong direction. That's why I was suggesting measuring the pressure with a tall glass of water, (or a pitcher). 20cmH2O is only about 8 inches.

IF you decide to test this in water make sure you have enuff room left for the water to bubble over. Cuz at 20cm you will make a mess with it. I would use a bucket w/about 10 or 12 in. of water but thats me.

Agreeing with CF again.

NEVER ACCEPT A LESSER MACHINE
Having used a Resmed (check spelling very carefully--off brands use similar names),
you need the same make/model, or a newer version of exactly the same thing.
Going from a Resmed to a Luna would be equivalent to trading in a Lincoln for a Yugo.
Don't let them scam you.

maybe drag out an old machine.

IF you have a spare I would use that and wait this shortage out. This is why a spare is soo important.

[ejbpesca]

If loss of seal at the water tank causes the top end 20cm pressure to occur.

That's not how the machine responds to large leaks. The machine will ramp up airflow to try and achieve the set pressure. If there's a huge leak, you're not going to get your desired pressure at the mask.

In cases of really severe leaks, the machines actually *LOWER* pressure to try and get masks to seal again. I've got a chart around here showing that exact thing.

I have numerous records of Large Leaks. None of them ever caused the machine to go to the level of high pressure I have described in this incident. Getting the water tank seals leak corrected solved the pressure problem. I do not know if that leak was large or severe, but it caused pressure to go to beyond the current max pressure setting. I know this from experience with the max pressure setting. This rogue pressure was way above it. I can only guess that this strange high pressure was the top 20cm the machine can produce. Note: If the pressure I experienced from this water tank leak is 20cm, I cannot imagine how that pressure level could give therapy. It was so intense, it was dangerous. Upon inhaling, cheeks blew fully out, air shoved into my lungs producing pain. The periphery of the mask (all three tested) blew outward making a seal impossible.

It, apparently for now, was the water chamber's lack of seal causing the machine to go into hyper pressure. Once the two water chamber seals were completed by working the chamber in and out, creating friction, and rubbing oxidation off them, (speculation), the pressure returned to normal. If that was a severe leak, no, the machine did not *LOWER* the pressure. If it were a large leak, the machine overreacted with a pressure level I've never experience in over ten years, of CPAP therapy.

I am not convinced the problem is just with the water chamber seal. The machine should have not produced, no matter what level of leak, such a high pressure. It happened in the night, me asleep. A sudden large increase in pressure inflated my lungs, blew the mask away from my face and of course wakened me. I shut the machine down then consulted CpapTalk, DME, and Resmed. CpapTalk advice prompted me to get the water tank to seal. As of 7 hours ago the machine returned to normal operation. I am nearing time to begin therapy tonight, but I am wary of it. I may forego tonight's therapy due to apprehension. To have pressure like that blasted into your lungs is an experience I feel is dangerous and a first for me in over 10 years of CPAP therapy.

Thank you for you for your replies.

[ejbpesca]

I wonder now if mask test mode sent the machine into producing more than 20 cm.

It's often very hard to separate these perceptions from reality, and end up going off in the wrong direction. That's why I was suggesting measuring the pressure with a tall glass of water, (or a pitcher). 20cmH2O is only about 8 inches.

IF you decide to test this in water make sure you have enuff room left for the water to bubble over. Cuz at 20cm you will make a mess with it. I would use a bucket w/about 10 or 12 in. of water but thats me.

Agreeing with CF again.

NEVER ACCEPT A LESSER MACHINE
Having used a Resmed (check spelling very carefully--off brands use similar names),
you need the same make/model, or a newer version of exactly the same thing.
Going from a Resmed to a Luna would be equivalent to trading in a Lincoln for a Yugo.
Don't let them scam you.

maybe drag out an old machine.

IF you have a spare I would use that and wait this shortage out. This is why a spare is soo important.

My last good 5 gal. bucket was ready to go, but getting the water tank to seal stopped the freaky high pressure. I do not think this was just a leak problem due to the very high pressure the machine produced. No need to test now it's back to normal. I hesitate to use it tonight though. The thing can literally blow you up. (Folks here find that hard to believe.) After over 10 years of CPAP therapy with every leak, this and that, I have never had one inflate my lungs then blow the mask off me till now.

[ejbpesca]

Now to deal with one of my old spare machines, a Philips recall. It is over 5 years service so Philips offers no replacement, but they may offer some payment to return it to a DME. My new local DME, 2 miles from me, is a place it can be taken. Waiting on the fax from clinic to DME, to get all in place.

Thanks so much to all for the advice here to help me hunt down and solve the high pressure problem!

Y'all are the best!

Check the recall thread. They are replacing older units, you just need to jump through all the hoops and reject their payoff offer.

Round two with Phillips produced the same statement, "Due to your machine being over the 5 years life expectancy, it does not qualify for replacement." I will attempt to leap through hoops, if I can recognize the hoops as they appear in order to go for a replacement. I'm 71, and finding mental sharpness not a quality I possess that I may have once had...I can't remember if I had it or not. Thank you all for your patience with me.

[ejbpesca]

So, what you had, based on Robysue's suggestion and your fix was not a high pressure problem,rather you had a high AIR FLOW problem which made a lot of noise, and made you think that there was a lot of high pressure, but if you had a massive leak at the humidifier, then you'd actually have LOWER pressure at the mask, if you think about it.

It's often very hard to separate these perceptions from reality, and end up going off in the wrong direction. That's why I was suggesting measuring the pressure with a tall glass of water, (or a pitcher). 20cmH2O is only about 8 inches.

I was going to use a 5 gal. bucket for this cm pressure test. Not a pressure problem? My reaction to the pressure was the hyperbole that it could inflate a truck tire. How could flow, without much pressure inflate my lungs and blow the mask away from my face? ??? Not being impertinent, just baffled. I am aware of the concept of pressure and flow in water pipes, but I don't think that applies to a CPAP machine that self regulates pressure, which in this incident, did not happen.

[palerider]

So, what you had, based on Robysue's suggestion and your fix was not a high pressure problem,rather you had a high AIR FLOW problem which made a lot of noise, and made you think that there was a lot of high pressure, but if you had a massive leak at the humidifier, then you'd actually have LOWER pressure at the mask, if you think about it.

It's often very hard to separate these perceptions from reality, and end up going off in the wrong direction. That's why I was suggesting measuring the pressure with a tall glass of water, (or a pitcher). 20cmH2O is only about 8 inches.

I was going to use a 5 gal. bucket for this cm pressure test. Not a pressure problem? My reaction to the pressure was the hyperbole that it could inflate a truck tire. How could flow, without much pressure inflate my lungs and blow the mask away from my face? ??? Not being impertinent, just baffled.

And without any actual *data*, all we've got is your perception, and perceptions are very often wrong, unfortunately.

[chunkyfrog]

For example, put a stretchy party balloon over the end of the hose;
then turn on the cpap. It will never fully inflate.
20 cm H2O will not inflate a regular balloon--maybe a Mylar balloon,
because they are already full size, requiring very light force.

[Pugsy]

What you feel or perceive as pressures of 20 cm doesn't necessarily mean that the machine actually went to 20 cm during the time the water chamber wasn't seated completely and a leak was happening.
I know it feels like 20 cm but it wasn't 20 cm.
These machines simply won't go to 20 cm just to try to "fix a leak"....they just don't do it.
Now does it feel like a hurricane...yeah, it probably does but that doesn't mean it is a hurricane.

Use available software detailed reports and look to see just exactly how high the pressure did go during the time of the leak.

[robysue1]

So, what you had, based on Robysue's suggestion and your fix was not a high pressure problem,rather you had a high AIR FLOW problem which made a lot of noise, and made you think that there was a lot of high pressure, but if you had a massive leak at the humidifier, then you'd actually have LOWER pressure at the mask, if you think about it.

It's often very hard to separate these perceptions from reality, and end up going off in the wrong direction. That's why I was suggesting measuring the pressure with a tall glass of water, (or a pitcher). 20cmH2O is only about 8 inches.

I was going to use a 5 gal. bucket for this cm pressure test. Not a pressure problem? My reaction to the pressure was the hyperbole that it could inflate a truck tire. How could flow, without much pressure inflate my lungs and blow the mask away from my face? ??? Not being impertinent, just baffled. I am aware of the concept of pressure and flow in water pipes, but I don't think that applies to a CPAP machine that self regulates pressure, which in this incident, did not happen.

Air flow and air pressure are two distinctively different things.

In order to achieve increasing the pressure above the ambient air pressure, you have to blow air into a closed or semi-closed space. If there are no leaks (think about inflating a tire), once you have blown enough air into the closed space, the pressure can be maintained with 0 airflow.

But an xPAP is not a closed system. It's a semi-closed system---in other words, there is a built in intentional leak so that we have a fresh air supply on each inhalation and so that the CO2 we exhale is vented out of the mask to prevent rebreathing the CO2. In order to increase the pressure above the ambient air pressure, you have to initially blow air into the system at a rate that is greater than the leak rate. But once the desired pressure level is reached, you only need to blow air into the system at the same rate air is being leaked out of the system.

To help make this clearer, let's look at some examples. Suppose your mask has an intentional leak rate of 20 L/min at the pressure your machine is currently set to maintain.

If your unintentional leak rate is 0 L/min, then the airflow into your mask will be pretty close to 20 L/min once the desired pressure is reached. If your mask springs a small unintentional leak of 5 L/min, then the machine compensates by increasing the airflow into the system to 20 + 5 = 25 L/min. The pressure remains the same, but the air flow has to be increased since more air is being lost through the leak.

If you wind up with a large unintentional leak of 25 L/min, the machine will attempt to compensate by increasing the airflow into the system to 20 + 25 = 45 L/min. The pressure remains the same, but there is substantially more air being blown through the mask, and our sensation of that increased air flow is often mistaken: Instead of it feeling like the wind speed has picked up, all that extra air flow can make it feel like the machine has decided to increase the pressure for some reason.

If you wind up having a humongous large unintentional leak of something like 50 L/min, the machine might not be able to compensate for the leak by increasing the airflow into the system to 20 + 50 = 70 L/min. And when that happens, APAPs are programed to decrease the pressure setting in an attempt to encourage the mask to seal. But even so, the air needed to try to maintain the decreased pressure setting will still require the machine to be blowing air into the leaky system at a rate that is at least equal to the rate air is being lost through the leaks. So even as the machine is decreasing the pressure setting, the air flow into the mask will still be substantially greater than your mask's intentional leak rate of 20 L/min. And our sensation of that significantly increased air flow is often mistaken: Instead of it feeling like the wind speed has picked up, all that extra air flow can make it feel like the machine has decided to increase the pressure for some reason.

To sum up: We sense the air flow into our masks in much the same way we tend sense wind blowing in our faces: The greater the air flow is, the faster that air is moving and the more perceptible it is. But at the same time, all that air is not just freely blowing past our faces---it's coming in through a small mask attached to a small part of our face and more or less is aimed at our upper airway. Hence when the machine significantly increases the air flow because the machine is trying to compensate for an unintentional leak, we can misperceive the additional airflow as an attempt to increase the pressure rather than the machine's working hard to maintain the current pressure setting.

[ejbpesca]

Here is OSCAR pressure graph the night before the pressure increase with settings of Min 8 Max 14.

Screenshot 2023-01-06 at 1.52.09 PM.png (36.51 KiB) Viewed 368 times

Flow noise discovered and mask not being able to seal I set machine to Min 8 Max 10 This is pressure report the next night evidently with water tank air leak.