BiPAP and Central Apnea

[thasan26]

Just got back from over night sleep study from a sleep health center this morning. The tech told me that when he put me on Bipap Mode last night, I had long Central Sleep apnea but then when he switched me to CPAP Auto (Settings 5 to 15) everything was fine. Does any one had similar experience where BiPAP caused Central Apnea?

[robysue]

For some people with central sleep apnea problems, the usually larger PS with a bilevel machine can trigger the problems with CAs.

It would be worth finding out if the tech had switched off the exhale relief system when he had you on the Auto CPAP.

[thasan26]

For some people with central sleep apnea problems, the usually larger PS with a bilevel machine can trigger the problems with CAs.

It would be worth finding out if the tech had switched off the exhale relief system when he had you on the Auto CPAP.

This is what the Sleep Tech recommended me for Auto CPAP settings:

Auto CPAP Pressure: 5 - 15
EPR / CFLEX: 1
NO RAMP

I am confused and don't know what to do because My health insurance already approved a BiPAP machine and My doctor ordered this sleep study to know the appropriate settings for a BiPAP. But, the sleep tech is saying above setting in a Auto CPAP works better because it did not caused that many Central Sleep apnea.

[robysue]

For some people with central sleep apnea problems, the usually larger PS with a bilevel machine can trigger the problems with CAs.

It would be worth finding out if the tech had switched off the exhale relief system when he had you on the Auto CPAP.

This is what the Sleep Tech recommended me for Auto CPAP settings:

Auto CPAP Pressure: 5 - 15
EPR / CFLEX: 1
NO RAMP

I am confused and don't know what to do because My health insurance already approved a BiPAP machine and My doctor ordered this sleep study to know the appropriate settings for a BiPAP. But, the sleep tech is saying above setting in a Auto CPAP works better because it did not caused that many Central Sleep apnea.

EPR or Flex set to 1 provides very minimal exhalation relief and would be equivalent to using a BiPAP with the PS = 1, or in other words, IPAP = EPAP + 1. The typical settings with a bilevel (BiPAP) have a greater PS setting that can be achieved with a CPAP or APAP.

Out of curiosity: Your signature shows you as having a Resmed AutoSet Spirit (S7? or S8?) So you been on CPAP for a while. What triggered the last round of sleep tests in the first place and why did the doc want a BiPAP titration done in the first place?

It sounds to me like you need to discuss the sleep study's results with your doctor. The tech who ran the test probably was not supposed to tell you anything about the results.

In other words, the doc is the one who is supposed to put the sleep study results in the context of your overall medical history. And the doc is the one who knows why he wanted a you to try bilevel.

Now if the doc agrees with the sleep tech that an APAP running 5-15 is the way to go, there are some things you might want to consider asking about:

1) 5-15 is a very, very wide APAP range, and most people do better with a more narrow range. In particular, the min pressure should not be more than 2-3cm below your 90% or 95% pressure level. If it is set much lower than that, too many events must occur before the machine raises the pressure to a level sufficient to control the apnea. So is the idea for you to use 5-15 to gather additional data before tightening the range? Or is there a reason to use such a wide range of pressures?

2) What was the specific reason the doc wanted a bilevel trial in the first place? If it was the suspicion that you have problems with central apneas, ask the doc what will happen if you upgrade to a new Resmed AirSense AutoSet or a PR DreamStation Auto CPAP and the machine continues to score a significant number of CAs.

[thasan26]

For some people with central sleep apnea problems, the usually larger PS with a bilevel machine can trigger the problems with CAs.

It would be worth finding out if the tech had switched off the exhale relief system when he had you on the Auto CPAP.

This is what the Sleep Tech recommended me for Auto CPAP settings:

Auto CPAP Pressure: 5 - 15
EPR / CFLEX: 1
NO RAMP

I am confused and don't know what to do because My health insurance already approved a BiPAP machine and My doctor ordered this sleep study to know the appropriate settings for a BiPAP. But, the sleep tech is saying above setting in a Auto CPAP works better because it did not caused that many Central Sleep apnea.

EPR or Flex set to 1 provides very minimal exhalation relief and would be equivalent to using a BiPAP with the PS = 1, or in other words, IPAP = EPAP + 1. The typical settings with a bilevel (BiPAP) have a greater PS setting that can be achieved with a CPAP or APAP.

Out of curiosity: Your signature shows you as having a Resmed AutoSet Spirit (S7? or S8?) So you been on CPAP for a while. What triggered the last round of sleep tests in the first place and why did the doc want a BiPAP titration done in the first place?

It sounds to me like you need to discuss the sleep study's results with your doctor. The tech who ran the test probably was not supposed to tell you anything about the results.

In other words, the doc is the one who is supposed to put the sleep study results in the context of your overall medical history. And the doc is the one who knows why he wanted a you to try bilevel.

Now if the doc agrees with the sleep tech that an APAP running 5-15 is the way to go, there are some things you might want to consider asking about:

1) 5-15 is a very, very wide APAP range, and most people do better with a more narrow range. In particular, the min pressure should not be more than 2-3cm below your 90% or 95% pressure level. If it is set much lower than that, too many events must occur before the machine raises the pressure to a level sufficient to control the apnea. So is the idea for you to use 5-15 to gather additional data before tightening the range? Or is there a reason to use such a wide range of pressures?

2) What was the specific reason the doc wanted a bilevel trial in the first place? If it was the suspicion that you have problems with central apneas, ask the doc what will happen if you upgrade to a new Resmed AirSense AutoSet or a PR DreamStation Auto CPAP and the machine continues to score a significant number of CAs.

I was not able to adapt to CPAP therapy. Then, I used oral appliance for last 5 years. Now, insurance won't pay for replacement oral appliance (old one broke). Last sleep study was done 8 years ago. So, doctor ordered a new sleep study.

[Sleeprider]

Just got back from over night sleep study from a sleep health center this morning. The tech told me that when he put me on Bipap Mode last night, I had long Central Sleep apnea but then when he switched me to CPAP Auto (Settings 5 to 15) everything was fine. Does any one had similar experience where BiPAP caused Central Apnea?

The problem is that the tech's summary does not specify what bilevel settings were tried, nor what "everything was fine" means at a variable CPAP pressure of 5-15. We know in your current CPAP therapy, you have a very high leak rate and that your treated AHI averages 8.8, mostly as hypopnea, at a 95% pressure of 8.6 cm. Your machine is incapable of differentiating CA from OA. source: http://www.apneaboard.com/forums/attachm...p?aid=2415

I would ask for some further details about the results under auto-CPAP, and if the leaks and events are actually good, I think your prescription will likely change to auto CPAP on that basis, especially since you did not receive a bilevel titration. How long did the tech observe you sleeping, and how many events at that pressure. If you tolerated the CPAP in the lab, then the assertion you do not tolerate CPAP is rejected along with the need for bilevel.

[robysue]

I was not able to adapt to CPAP therapy.

What were your specific problems?

The facts that I had severe aerophagia at low CPAP/APAP pressures and a serious case of growing CPAP-induced insomnia were what the sleep doc used in his memo of medical necessity to the insurance company for my BiPAP. My first BiPAP study was not very successful---it primarily demonstrated that my insomnia was even worse that I thought it was. But the sleep doc was willing to order a BiPAP anyway. And the insurance company didn't balk at it.

Then, I used oral appliance for last 5 years. Now, insurance won't pay for replacement oral appliance (old one broke). Last sleep study was done 8 years ago. So, doctor ordered a new sleep study.

Was the study a split study? or a just a titration study? Why did the doc order a bilevel study?

[thasan26]

I was not able to adapt to CPAP therapy.

What were your specific problems?

The facts that I had severe aerophagia at low CPAP/APAP pressures and a serious case of growing CPAP-induced insomnia were what the sleep doc used in his memo of medical necessity to the insurance company for my BiPAP. My first BiPAP study was not very successful---it primarily demonstrated that my insomnia was even worse that I thought it was. But the sleep doc was willing to order a BiPAP anyway. And the insurance company didn't balk at it.

Then, I used oral appliance for last 5 years. Now, insurance won't pay for replacement oral appliance (old one broke). Last sleep study was done 8 years ago. So, doctor ordered a new sleep study.

Was the study a split study? or a just a titration study? Why did the doc order a bilevel study?

When I try to use my current CPAP mechine, I sometimes take off the mask at night in a sub-conscious state. I don't even remember it in the morning. Another problem is, it is difficult for me to exhale when the pressure goes up. Because, of these reasons doctor ordered the BiPAP titration study. It was not a split study. I had the home sleep study done about 2 weeks ago and lasy night was titration study only.

[thasan26]

Just got back from over night sleep study from a sleep health center this morning. The tech told me that when he put me on Bipap Mode last night, I had long Central Sleep apnea but then when he switched me to CPAP Auto (Settings 5 to 15) everything was fine. Does any one had similar experience where BiPAP caused Central Apnea?

The problem is that the tech's summary does not specify what bilevel settings were tried, nor what "everything was fine" means at a variable CPAP pressure of 5-15. We know in your current CPAP therapy, you have a very high leak rate and that your treated AHI averages 8.8, mostly as hypopnea, at a 95% pressure of 8.6 cm. Your machine is incapable of differentiating CA from OA. source: http://www.apneaboard.com/forums/attachm...p?aid=2415

I would ask for some further details about the results under auto-CPAP, and if the leaks and events are actually good, I think your prescription will likely change to auto CPAP on that basis, especially since you did not receive a bilevel titration. How long did the tech observe you sleeping, and how many events at that pressure. If you tolerated the CPAP in the lab, then the assertion you do not tolerate CPAP is rejected along with the need for bilevel.

Tech told me that he started the titration study with BiPAP last night then when the CAs started to occur, he changed it to Auto CPAP. I am expecting the full sleep study report early next week. Then, we will know better. Sleep study lasted from 10:30 PM to 5 AM this morning. I did not have a complete sound sleep during the sleep study. I woke up 3 or 4 times while the sleep study was going on.