For those who have low AHIs ( < 5 ), how long did it take you to reach such low levels?

I'm on day one with my APAP, and averaged 10.1. For the last hour, my AHI ( Obstructive Apna ) shot up to 23.7. Is it normal to get high AHIs the first couple of weeks?

What can I do to reduce the AHI?

What are my options?

Increase Pressure?
Lower Pressure?
Turn off AFlex?


_________________
5'9 234lbs 37 years Old Male
Original Sleep Study: AHI = 30

Owner of Remstar Auto A Flex M series
ResMed Ultra Mirage Full Face Mask
Viewer 1.0 Software, Smartcard Reader
Integrated Heater/humidifier
Prescribed setting: 7-10 Cm

The way to lower the AHI is through determining the proper device as well as the optimal  pressure needed to treat your specific condition.

First, did you undergo an overnight titration study (patient is wearing the mask) in the sleep lab? If so, then
What was the optimal pressure setting determined to be? What was your AHI at that pressure setting or range?
Also, what specific type of sleep apnea were you diagnosed with?

This info should be available either through the doc or through looking at the full sleep study report.

Anonymous wrote:

The way to lower the AHI is through determining the proper device as well as the optimal  pressure needed to treat your specific condition.

First, did you undergo an overnight titration study (patient is wearing the mask) in the sleep lab? If so, then
What was the optimal pressure setting determined to be? What was your AHI at that pressure setting or range?
Also, what specific type of sleep apnea were you diagnosed with?

This info should be available either through the doc or through looking at the full sleep study report.

Yes, I went through an overnight titration. The optimal pressure was 10cm, and my AHI at that pressure during the Titration was 0.

I was diagnosed with Obstructive Sleep Apnea, not Central or any other Apnea.


I just received my APap machine, set at a range from 7-10. And my first night, I averaged 10.1 AHI, but during my 5 hour sleep, on my 4-5th hour, my AHI shot up to 23.7.

I'd like to reduce my overall AHI to <5.


_________________
5'9 234lbs 37 years Old Male
Original Sleep Study: AHI = 30

Owner of Remstar Auto A Flex M series
ResMed Ultra Mirage Full Face Mask
Viewer 1.0 Software, Smartcard Reader
Integrated Heater/humidifier
Prescribed setting: 7-10 Cm

My guess is that you developed a leak or you were mouth breathing if you have a nasal mask.

sleepIsHell wrote:

Yes, I went through an overnight titration. The optimal pressure was 10cm, and my AHI at that pressure during the Titration was 0.

I was diagnosed with Obstructive Sleep Apnea, not Central or any other Apnea.

Some labs don't look for, diagnose, or treat Complex sleep apnea. This involves the appearance of a significant number of central apneas during the titration study. It would not hurt to double check for it.

sleepIsHell wrote:

I just received my APap machine, set at a range from 7-10. And my first night, I averaged 10.1 AHI, but during my 5 hour sleep, on my 4-5th hour, my AHI shot up to 23.7.

In Obstructive apnea, the condition is often worse when either sleeping on the back (supine position) or during REM sleep. Check to make sure that those conditions were covered during the titration.

Also, what did the leak rate data look like during that hour?

sleepIsHell wrote:

I'd like to reduce my overall AHI to <5.

It might be helpful to get a copy of the full report from the titration study and post it in the sleep studies section to see if anyone has any helpful feedback.

Quote:

Some labs don't look for, diagnose, or treat Complex sleep apnea. This involves the appearance of a significant number of central apneas during the titration study. It would not hurt to double check for it.

I checked my report, and there were no Central Apneas. Zero. I was diagnosed with Obstructive Sleep Apnea. Could they have missed Complex or Central Apneas?

Quote:

In Obstructive apnea, the condition is often worse when either sleeping on the back (supine position) or during REM sleep. Check to make sure that those conditions were covered during the titration.

During the Titration, I only slept on supine position, no other. This is the position I normally sleep in. I rarely sleep in any other position.

Quote:

Also, what did the leak rate data look like during that hour?

Overall, my Leak rate last night was 35. I use a Mirage Ultra Full Face Mask. The Leak Rate did increase during that 4th hour, but only after my sleep apneas increased, and then the machine kicked in the higher pressure, going from 7-10, and my leak rate increased during that time.


_________________
5'9 234lbs 37 years Old Male
Original Sleep Study: AHI = 30

Owner of Remstar Auto A Flex M series
ResMed Ultra Mirage Full Face Mask
Viewer 1.0 Software, Smartcard Reader
Integrated Heater/humidifier
Prescribed setting: 7-10 Cm

I've been on straight CPAP for about 17 nights now.  My doc requested the pressure be set to 9cm.  It was quite hard for me to get used to that pressure, I used ramp to get to sleep the first couple days, still awoke every 60 to 90 minutes at night and it took 20 minutes or longer to get back to sleep each time... But my AHI was around 3.  I figured out how to lower my pressure and lowered it to 6 for a couple days, AHI went up to 4.5 or so, still kept waking up five or six times a night... I raised my pressure up gradually, the AHI went down... I settled on 8CM and my AHI's are under < 0.5 most nights. I'm sleeping for 6 hours or so now, waking no more then twice a night...  

I lost the first few days of data... but here's the last couple weeks worth... I've been at 8cm since the 30th of April. However as I say, I've never been above 5 AHI while in CPAP... my sleep study AHI was 59...   I use Respironics REMstar M-Series Pro, with humidifier set at 1, Swift II nasal pillow... I've been taping my mouth shut most nights for the past week, but lowest AHI so far was last Saturday  night when I was so tired I fell asleep and had forgot to tape my mouth shut... So, I don't think it's the tape that has caused my AHI to go down and stay down... but then who knows, I suspect that my body has just gotten used to CPAP.





Last edited by sleepy42 on Sat May 10, 2008 8:27 pm; edited 1 time in total

OH... your question...

  I don't use Auto PAP... however I was reading about a guy on cpaptalk dot com, who is... he showed some data where his AHI is highest when his machine goes to the highest pressure...  I'm not at all a expert on these matters, however it seems that to high a pressure can be as bad as to low...   As I understand it, when the machine detects snores... it raises the pressure.  For me, looking at my data, snore scores have no correlation to my AHIs... My worst snore score was on May 4th, I had a average of 40 snores per hour according to my machine, and yet my AHI was less  then my average is...

I personally am somewhat skeptical about the effectiveness of APAP...  I've got little total experience, but I'm leaning toward a belief that finding a single pressure, or at the minimum a narrow range of pressures my very well be more effective then a auto PAP with a wide swing...   For me... straight CPAP seems to work just fine.   the 8cm I'm at now is quite easy to take... I've lowered my c-flex to 1, never use ramp at all any longer... when the pressure first blows, it bothers me for about 30 seconds, after that it's quite comfortable...

sleepIsHell wrote:

I checked my report, and there were no Central Apneas. Zero. I was diagnosed with Obstructive Sleep Apnea. Could they have missed Complex or Central Apneas?

The first study, the Diagnostic study, is not helpful to diagnose Complex. If you did not have any Central apneas during the Titration study, then it can be ruled out.

sleepIsHell wrote:

During the Titration, I only slept on supine position, no other. This is the position I normally sleep in. I rarely sleep in any other position.

Ok  on the supine position. Then what was your percentage of REM sleep stage during the titration study?
 

sleepIsHell wrote:

Overall, my Leak rate last night was 35. I use a Mirage Ultra Full Face Mask. The Leak Rate did increase during that 4th hour, but only after my sleep apneas increased, and then the machine kicked in the higher pressure, going from 7-10, and my leak rate increased during that time.

I don't know the leak rate for the Mirage Ultra, but you can check it. There should be some info about the leak rate in the documents that come with the mask. There should be a table that shows the acceptable leak rate at different pressures.

Is there anything else that could have been different between the titration study night, and the treatment at home, and that might explain the higher AHI? For example, did you drink any alcohol with dinner? or was there any change in medications?

I would probably give it a few nights to see if that was an off-night. If not, then I would consider discussing with the sleep doc increasing the pressure, like 10-14cm.

sleepy42;  AutoPAP is a great tool for titrating CPAP, but in some circumstances, autoPAPs can be fooled into providing too much pressure and too high of a pressure can induce centrals.  I think that autoPAPs are normally best used in auto mode for a few days to get a titration and then clamped into straight CPAP mode.

My doc. doesn't prescribe APAPs because the algorithms have a ways to go and all kinds of things will elicit a pressure increase, leaks, snores, etc.  I also do better on CPAP mode.   I was running in APAP mode though this week because I've lost weight.  My doc and I knew I needed a major pressure decrease and we put it into APAP mode until I got to the sleep lab last night.  My doc. asked what pressure my APAP was showing, but I wasn't using the APAP that is data capable.

Vicki


_________________
That which does not kill you makes you stronger-Friedrich Nietzsche
Friedrich must of had apnea.

If Auto PAP machines can't be trusted to do the correct thing with regard to pressure, it seems that their value in any kind of Auto titration is suspect at best. It would seem to me that if a patient were given a bit of education and the ability to adjust pressures themselves and given access to full data from the CPAP,  a self titration could be just as effective, perhaps more so.  

While researching info to help me get though my own problems adjusting to CPAP I came across some interesting articles that suggest there is some evidence that patients allowed to make adjustments to their own pressure and/or titrate themselves do quite well...  I can't no locate the original article that I found that came to that conclusion, but have found another that seems to suggest the same...

http://findarticles.com/p/articles/mi_qa4085/is_200303/ai_n9189167

For me, feeling a bit empowered and having a bit of control over my own destiny was an enormous boost to my moral and probably greatly contributed to my getting used to sleeping well on CPAP. If my machine had been doing auto adjustment of pressure and I was still getting high AHI numbers, I would have been even more frustrated and less likely to adjust to the whole CPAP experience.

AutoPAPs are generally accurate over a period of time and as such they are a valuable tool for titration, the problem is that they may not necessarily be accurate at any given time.