Autoset vs CPAP

I received a new ResMed S9 Autoset yesterday. I had been using a ResMed S8 Elite for the past 5 years. Tonight, in trying out the S9, I find that I'm having trouble getting used to the Autoset feature vs the CPAP mode. My pressure is supposed to be set at 13. I notice that the Autoset pressure range is set to 4-20. I see that some members here have adjusted the low pressure higher re: 10-20 etc. Does having a higher low pressure defeat the purpose of autoset? Starting off at a pressure of 4, makes me feel as if I'm not getting enough air or having to struggle on inhalation. Probably because I've been used to the Cpap 13 setting with ramping turned off on the S8, all those years, but I'm wondering if others have had a hard time getting used to autoset, perhaps thus the reasons for the higher pressure low numbers I am seeing. Thanks

4 is the machine's default low setting as 20 is the high one. Either your MD did not give your DME a prescribed setting for you, the DME did not enter one, you didn't have a formal sleep study (and are possibly supposed to titrate yourself at home?) or someone was just lazy. In any case, no one can breathe at 4 and no one is actually prescribed that - you're machine's been left open for you to find out what your pressure settings should be, but the trouble is, is you have events at e.g. 9 or 15, or 18, there's no way the low pressure can get up there fast enough to intercept them, so it's a waste of time as it is now. Yes, do raise it a couple of cms anyhow, but much better would be to get your sleep study results from your doctor to see in fact what # would be best to start with... it would be one where you theoretically spent 90-95% of your sleep time.

Thanks Julie. That all makes sense, especially re: the low pressure of 4. I will increase that and see how that works/feels. As far as prescription, from my most recent sleep study, all I was told was that my S8 needed to be set at 13, which I did myself.

If you were only given one setting, that would indicate that you're supposed to do 'only' cpap vs auto, but if you have an auto machine you can do both. However, I'd talk to your MD about that ... why you were prescribed only cpap.

That "only one setting" was from when I had the ResMed S8 CPAP. The RT at Apria just set the S9 Autoset up on CPAP, but told me that Autoset was available. He left the Autoset pressures at what I believe were the machines defaults of 4-20. After reading several similar posts, I think I'll raise my low pressure to a 9 or 10 or maybe just stick with CPAP for a while. Thanks again.

Also... some folks respond to cpap mode vs auto set mode differently. I have used cpap mode, autoset mode and vpap mode, and I have always migrated back to the cpap mode. I feel better with the cpap mode. That's just me... and we are all different. Just sayin'

Sheriff

Digeeedad wrote:I think I'll raise my low pressure to a 9 or 10 or maybe just stick with CPAP for a while.

10 cm minimum would be most likely a lot more comfortable for you along with doing a better job getting to where it deals with any events that you might need 13 cm for.
Use the software available to see if you need 13 for just some of the night or maybe just a short period of time during the night.

I was titrated at 13 cm's just like you Digeeedad. I was given a CPAP for a month or so and I went to the S8 Autoset Vantage because I had visited these forums at the time and I got lucky and got what I wanted, although my original CPAP was Phillips Respironics. It would give the Doctor data but no provide me much to work with. Anyway, my pressure setting on APAP is 10 to 16, which is +3 and -3 from 13. Seems to work just fine. I also got that fine tuning from this forum. I used to ramp for 5 minutes but now I have it set for 15 minutes. There were times at first that I thought 10 was too low but I got used to it. It's just fine now.

I've had this APAP for about 9 years now and still going strong. An odd thing happened today though. For the first time in years I went to check the data in the clinician menu and there was only data for today only, nothing for the week, nothing for the month, and nothing for 6 months. Just today only. This explains why my APAP couldn't transfer data via the Resmed scan card to my new Sleep Doctor, although I tried twice. There's no data to transfer. First time I've heard of that.

Thanks for all of the informative replies everybody!

Digeeedad wrote:I received a new ResMed S9 Autoset yesterday. I had been using a ResMed S8 Elite for the past 5 years. Tonight, in trying out the S9, I find that I'm having trouble getting used to the Autoset feature vs the CPAP mode. My pressure is supposed to be set at 13. I notice that the Autoset pressure range is set to 4-20. I see that some members here have adjusted the low pressure higher re: 10-20 etc. Does having a higher low pressure defeat the purpose of autoset? Starting off at a pressure of 4, makes me feel as if I'm not getting enough air or having to struggle on inhalation. Probably because I've been used to the Cpap 13 setting with ramping turned off on the S8, all those years, but I'm wondering if others have had a hard time getting used to autoset, perhaps thus the reasons for the higher pressure low numbers I am seeing. Thanks

You haven't mentioned whether you were using software or monitoring your therapy in some manner.
I would recommend setting your machine up as closely to your previous machine , using it that way for about a week and see what the data looks like. ResScan or Sleepyhead are available to create reports from the data.


Den

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Digeeedad wrote:I notice that the Autoset pressure range is set to 4-20. I see that some members here have adjusted the low pressure higher re: 10-20 etc. Does having a higher low pressure defeat the purpose of autoset? Starting off at a pressure of 4, makes me feel as if I'm not getting enough air or having to struggle on inhalation.

the autoset defaults to 4-20 (factory setting) because the factory has no idea what your needs are, but they're probably somewhere in between those numbers

you need a certain amount of pressure to keep your airway open, but different people need different amounts.

an autoset on default settings will work for you, but, if you need 13cm to keep your airway open, you'll have problems during the minutes that it takes the autoset to raise pressure. it's better to set the starting point a little below where you need it, that way you won't have as many problems because it doesn't have as far to go to get to the pressure you need. starting at minimum only makes sense if you're trying to figure out what kind of pressure you need.

does that make sense?

palerider wrote:

Digeeedad wrote:I notice that the Autoset pressure range is set to 4-20. I see that some members here have adjusted the low pressure higher re: 10-20 etc. Does having a higher low pressure defeat the purpose of autoset? Starting off at a pressure of 4, makes me feel as if I'm not getting enough air or having to struggle on inhalation.

the autoset defaults to 4-20 (factory setting) because the factory has no idea what your needs are, but they're probably somewhere in between those numbers

you need a certain amount of pressure to keep your airway open, but different people need different amounts.

an autoset on default settings will work for you, but, if you need 13cm to keep your airway open, you'll have problems during the minutes that it takes the autoset to raise pressure. it's better to set the starting point a little below where you need it, that way you won't have as many problems because it doesn't have as far to go to get to the pressure you need. starting at minimum only makes sense if you're trying to figure out what kind of pressure you need.

does that make sense?

BUT.......it depends on whether there are "events" (Flow Limitations and/or Snores) to trigger pressure increases. The "frank" (out of nowhere) apneas will not trigger pressure increases alone, and will occur without an attempt to stop them.

It's best to set the minimum pressure to the point which will prevent ALMOST ALL of the the events.


Den

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Wulfman... wrote: BUT.......it depends on whether there are "events" (Flow Limitations and/or Snores) to trigger pressure increases. The "frank" (out of nowhere) apneas will not trigger pressure increases alone, and will occur without an attempt to stop them.

It's best to set the minimum pressure to the point which will prevent ALMOST ALL of the the events.

um, that's not quite right, Den. autosets *do* respond to hypopneas and obstructive apneas, just not as aggressively as they do to the precursors (snores and flow limitations.)

it's documented, (though I don't have it to hand) and you can see it if you poke around in enough autoset data.

they won't boost pressure for a single event, in the name of "well, it was just one and a pressure increase may be disturbing", but if you have another one within a certain amount of time, then pressure will increase.

Robysue has posted more details about how fast the autosets respond to apneas and hypops and when they leave them alone to see if things will stay ok.

I agree it's best to have minimum pressure around where normal events are handled, ie, non-rem, side sleeping events, but not to have minimum cranked up further to handle the rem, or brief back sleeping some people do. again, no blanket settings, but more tailored for the individual.

palerider wrote:

Wulfman... wrote: BUT.......it depends on whether there are "events" (Flow Limitations and/or Snores) to trigger pressure increases. The "frank" (out of nowhere) apneas will not trigger pressure increases alone, and will occur without an attempt to stop them.

It's best to set the minimum pressure to the point which will prevent ALMOST ALL of the the events.

um, that's not quite right, Den. autosets *do* respond to hypopneas and obstructive apneas, just not as aggressively as they do to the precursors (snores and flow limitations.)

it's documented, (though I don't have it to hand) and you can see it if you poke around in enough autoset data.

they won't boost pressure for a single event, in the name of "well, it was just one and a pressure increase may be disturbing", but if you have another one within a certain amount of time, then pressure will increase.

Robysue has posted more details about how fast the autosets respond to apneas and hypops and when they leave them alone to see if things will stay ok.

I agree it's best to have minimum pressure around where normal events are handled, ie, non-rem, side sleeping events, but not to have minimum cranked up further to handle the rem, or brief back sleeping some people do. again, no blanket settings, but more tailored for the individual.

It takes 10 seconds to "define" an apnea as such (or a hypopnea). Without preceding events, that's a pretty short time and if it's a singular event, it will occur without a response.

When you find the documentation, I'll be glad to read it. I realize some of the technology has changed over the years, but I'm skeptical about them addressing apneas without preceding events.

By the way, I'm only talking about responses to apneas and not hypopneas. It all depends on the "shape" of the airflow to the sensors and algorithms.


Den

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Wulfman... wrote:It takes 10 seconds to "define" an apnea as such (or a hypopnea). Without preceding events, that's a pretty short time and if it's a singular event, it will occur without a response.

When you find the documentation, I'll be glad to read it. I realize some of the technology has changed over the years, but I'm skeptical about them addressing apneas without preceding events.

By the way, I'm only talking about responses to apneas and not hypopneas. It all depends on the "shape" of the airflow to the sensors and algorithms.

well, that didn't take as much digging as I figured it would.

http://www.resmed.com/int/clinicians/co ... nc=dealers
for the older s8: http://www.resmed.com/assets/documents/ ... ow_eng.pdf