Internet bought machine, how to get checked?

[john_dozer]

I bought a S9 Autoset from CPAP.com. I'm getting instaneously flow traces that I swear look like I'm having events. Basically it goes really low, followed by really large breathing which I call 'make up' breathing or gasping. Sometimes only about 1/3 of these events are flagged as anything. I would think they should at least be flagged as hyponeas. I know that S9 seem to lack sensitivity, but this is just missing too much.

How do I get the machine checked out? Contact CPAP.com or Resmed? Am I likely going to get a bill for getting it checked out. If I need to ship it, I fortunately have a CPAP (non-autoset) to use as a backup. Which won't be too different, because I've basically had to pull up the floor on pressure on the Autoset because its essentially going 30 or 40 minutes sometimes without reacting to a solid chain of what I consider some kind of event.

Sorry, I couldn't find an old post on the discussion. Usually just discussions about dealing with an insurance DMEs came up. I'm going to contact CPAP.com customer support, but would just like to have some idea what I'm in for.

I did buy the machine outright because I didn't go into my original DME armed with knowledge and let myself get stuck with a dumb brick machine that didn't even give you a summary in the morning, let alone record real-time data. And so replacing it was going to be out of pocket regardless. Is going to the DME an option?

[Mary Z]

I would call CPAP.com.. Your machine is under warranty.
Good luck. Keep us posted.

[avi123]

[quote="john_dozer"]I bought a S9 Autoset from CPAP.com. I'm getting instantaneously flow traces that I swear look like I'm having events. Basically it goes really low, followed by really large breathing which I call 'make up' breathing or gasping. Sometimes only about 1/3 of these events are flagged as anything. I would think they should at least be flagged as hyponeas. I know that S9 seem to lack sensitivity, but this is just missing too much.

[quote]

Could you explain more the above. IMO, the S9 Autoset is too sensitive to events and pseudo events. Firstly, the machine does not know when you're asleep or awake. So you can lay down awake for an hour "nap" in the p.m. and the machine would flag all kinds of events. Next, the machine would add these flags to your night sleep events later on. Secondly, if your mask leak is close to 24 L/Min then the machine can't diagnose the event.
As to gasping, sneezing, yawning, etc., the machine would not diagnose them as events but as flow limitation, leaks, etc.
As to hypopneas the machine does a poor job diagnosing them. See what Resmed's chief designer of the S8 and S9 Aoutosets said about hypopneas:

Q & A


From an interview with Dr Michael Berthon-Jones, in 2002.

Why is it important for an automatic CPAPdevice
to respond to flow limitation, snore and apnea?

The characteristic flattening of the flow-time
curve caused by flow limitation is the very best
signal for fine-tuning the pressure, once you have
eliminated apneas and snoring. But if you are just
falling asleep, you can go very quickly from having
a totally open airway to snoring very loudly, in a way
that produces somewhat chaotic or messy flowtime
curves, without seeing the characteristic
flattening. So the best approach is to respond very
quickly to loud snoring, and then fine tune using
flattening. Rarely, you can go straight from awake
and unobstructed to asleep and apneic, and so it
can be useful to increase pressure in response to
apnea as well. However, actual apnea is pretty rare
on AutoSet, because in most cases the responses
to snoring and flattening get the pressure up
quickly enough to prevent apneas.


Why doesn’t ResMed's AutoSet respond to
hypopnoea?

When you are lying quietly awake, or when you
first go to sleep, or when you are dreaming, you
can have hypopneas (reductions in the depth of
breathing) which are nothing to do with the state of
the airway. For example if you sigh, which you do
every few minutes, you usually have a hypopnea
immediately afterwards. This can also happen if
you have just rolled over and are getting settled, or
if you are dreaming. And the annoying thing is that
when you are on CPAP, this tendency to have what
are called central hypopneas - hypopneas that are
nothing to do with the state of the airway - is
increased. If you make an automatic CPAP device
that responds to hypopneas, you will put the
pressure up to the maximum while the patient is
awake.

Do you think there is a misconception clinically
that all hypopneas should be treated ?

For simple obstructive sleep apnea, central
hypopneas should not be treated. They are not a
disease. Everyone has them. And they don’t go
away with CPAP.

There is a rare and important exception: central
hypopneas due to heart disease. This is called
Cheyne-Stokes breathing. CPAP does help with
that.

Why doesn’t ResMed's AutoSet respond to
apnea above 10 cmH2O in pressure?

I mentioned before that the higher the pressure,
the more central hypopneas you will have. At a
pressure somewhere around 10 cmH2O, the central
hypopneas become central apneas. On the other
hand, the vast majority of obstructive apneas are
already well controlled by 10 cmH2O, and we are
only fine tuning using snoring and flattening. So it
is a pretty good bet that if the pressure is already
above 10 cmH2O, any apneas are most likely
central, and you should leave them alone (except
in patients with central apneas due to heart failure).
But if the pressure is below 10 cmH2O, most
apneas will be obstructive and you should put the
pressure up. There’s nothing magical about 10
cmH2O, it’s just a good place to put the line in the
sand.

Can you over-treat apnea?

You can’t over-treat obstructive apnea. You
really don’t want the patient having unresolved
obstructive apneas. And we want not just to prevent
apnea - we also want to keep the airway sufficiently
open for the subject to breathe easily and regularly
and stay asleep.

But you can use too much pressure. The higher
the pressure, the greater the side effects. Although
this has never been proven, it is rather obvious - no
pressure, no side effects! So you want to use the
lowest pressure possible while keeping the airway
nicely open.

Likewise can a device that responds to
hypopnea over-treat it ?

The funny thing is that it can both over-treat and
under-treat. It will put the pressure up through the
roof in some subjects, who have lots of central
hypopneas. And it can completely miss repetitive
severe silent inspiratory flow limitation that is totally
disturbing the patient’s sleep without there being
any hypopneas. If this occurs without CPAP, it is
called upper airway resistance syndrome. It is just
as bad for you as obstructive sleep apnea. But a
CPAP machine that responds only to hypopneas
will treat your obstructive sleep apnea, and give
you upper airway resistance syndrome instead.

How can Automatic CPAP devices help
optimise treatment ?

CPAP devices, whether automatic or not, can
tell us - the clinician, the technician - about what is
going on when we are not there. Is the patient using
the device? Is there a leak, and if so, when and how
much? If it is an automatic device, what is the
pressure doing? How well is the patient breathing?
How steadily, how much? This might be particularly
important if the patient also has heart disease or
lung disease, or has had a stroke, and has other
reasons, apart from sleep apnea, for having
abnormal breathing during sleep.
**************************************

As to using the S9 Autoset in the APAP mode you need to be careful that it is right for you.
Many underlying medical conditions render the the machine NOT appropriate in the APAP mode.

p.s. answering your direct question: I doubt it that CPAP.com could check your S9 but give you another one and send your to Resmed.

[idamtnboy]

I bought a S9 Autoset from CPAP.com. I'm getting instaneously flow traces that I swear look like I'm having events. Basically it goes really low, followed by really large breathing which I call 'make up' breathing or gasping. Sometimes only about 1/3 of these events are flagged as anything. I would think they should at least be flagged as hyponeas. I know that S9 seem to lack sensitivity, but this is just missing too much.

How about posting a copy of the graph so we have a clearer idea what you are referring to? It may be quite usual but just looks weird, and then again....

[archangle]

How long do they last? Short events don't count.

Graphs are probably a good idea.

I doubt there's ANY way to get a machine checked for what you're asking about. Any DME or service center is probably going to simply test to see if it's putting out the right pressure. I doubt if there's anyone who will be "authorized" to evaluate how the machine "scores" events. After all, "The computer is always right."

If you did manage to get in contact with someone at the company, they'd probably tell you that only medical professionals are qualified to look at the data. Given that it's ResMed, they'd probably threaten you with a lawsuit. (Only half joking.)

[msradar65]

Please ge tthe clinical manual from a member here on the site. I also have an S9 autoset and I run it in straight CPAP mode. Sounds like the ramp is set for a long period of time. You can turn the ramp off. Again the clinical manual has all the information that you need.

As far as setting the pressure you can check that with a manometer if you are in doubt. Once you get the manual a lot of your questions will be answered and you can customize the machine to your needs.

I love my S9 autoset and would never use a different machine. Then again its my first CPAP.

[john_dozer]

Please ge tthe clinical manual from a member here on the site. I also have an S9 autoset and I run it in straight CPAP mode. Sounds like the ramp is set for a long period of time. You can turn the ramp off. Again the clinical manual has all the information that you need.

As far as setting the pressure you can check that with a manometer if you are in doubt. Once you get the manual a lot of your questions will be answered and you can customize the machine to your needs.

I love my S9 autoset and would never use a different machine. Then again its my first CPAP.

Thanks for the offers to look at my charts, and I'll post a few in the next day or two, but getting the machine checked is something my doctor asked me to do.

I don't have any ramp though.

To another poster, I understand the S9 may not react to hyponeas or be slow to react to them, but I'm talking at times about it not even flagging what seem like some kind of event or flagging them as unknown at best.