Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account


New Posts   Today's Posts

Why are my med and 95 percents higher with narrower range?
#1
Hi Y'all,
This may be obvious to others but I haven't puzzled this out yet.
Looking over the last 45 or so days, I note that my median and 95 percent pressures are slightly higher as time has gone on. That may be a coincidence or that may be due to the narrow range perhaps?

They were somewhat lower avg in the 5-20 pressure range, than at the 7-14 range. Anyone know why this might be?

Also had good trend going with 3 or 4 days of AHI under 5.0 and then since new pillows on mask (prob coincidence) higher again. Still feel pretty good. Still less night loo trips (though far from gone) Just in case it was the new pillows, I swapped them back to the old one's two hours into night to see if it made a diff, noting that at the swap time I was having 9.9 events per hour.

I do have to say I like the nose pillows a bit broken in. Am I alone in this?

Sunshiney day here in S.F
Hope you all are having good days and better nights.
Susan
The Manse Hen
Reply
#2
Median pressure going up can be explained by general mathematical rules of statistics. Median is the value that is in the center of the sampled data. If you are going to move up the lower bound of the sample, the center will likely shift up.

95% pressure going up can not be explained by math alone. Since you are changing masks during this process, that may effect it.

In my experience of titrating from 4-20 to 7.5-15, I have seen my 95% pressure to be in similar range for the same mask. It did drop appreciably once I went to Nasal Pillows (P10) from a FFM (F10), from 10-11 to less than 9.0.
Started APAP 4-20, Closed range to 7.5-14, then straight 8.0 w/ Aflex 3
RDI always below 1. But sleep much much better at straight pressure.
Started on F10, Tried Quattro Air successfully. Finally settled on P10.
Reply
#3
The higher average pressures are most probably due to the increase in your minimum pressure. The machine is able to reach an effective pressure more quickly when you give it a head start. It will also be constrained from dropping as far as it may have been with the lower min pressure. So, yes, the average pressures may be somewhat higher than when the min. pressure was lower. It "should" also help your AHI.

Best Regards,

PaytonA
Reply


#4
And PeytonA gets the right answer! The median value is actually the most frequently occurring pressure, not the middle value (mean).

When you increased the minimum pressure, you intercepted some apnea, but also, with the machine starting at a higher pressure, the snores and flow limitations that are the basis for increasing auto pressure, caused a higher median and 95% pressure to be scored.

Your other questions might be better answered if you posted some data. Sounds like treated AHI is still relatively high.
______________________________________________
Organize your SleepyHead Data
Post your SleepyHead Data from Imgur
Robysue's Beginner's Guide to Sleepyhead
Reply
#5
(02-11-2015, 05:12 PM)TheManseHen Wrote: Hi Y'all,
This may be obvious to others but I haven't puzzled this out yet.
Looking over the last 45 or so days, I note that my median and 95 percent pressures are slightly higher as time has gone on. That may be a coincidence or that may be due to the narrow range perhaps?

They were somewhat lower avg in the 5-20 pressure range, than at the 7-14 range. Anyone know why this might be?

Also had good trend going with 3 or 4 days of AHI under 5.0 and then since new pillows on mask (prob coincidence) higher again. Still feel pretty good. Still less night loo trips (though far from gone) Just in case it was the new pillows, I swapped them back to the old one's two hours into night to see if it made a diff, noting that at the swap time I was having 9.9 events per hour.

I do have to say I like the nose pillows a bit broken in. Am I alone in this?

Sunshiney day here in S.F
Hope you all are having good days and better nights.
Susan
The Manse Hen

Hi Susan from Sunshiny S.F. .....wish you could send me some sun here in snowy Ohio! I have to take vitamin D instead!
When I started to change my pressure numbers from 4 to 20 to my current 8 to 14,
I also noticed the 90% range went up too. It means the machine is reaching the pressure that it needs to clear an apnea faster., and stays at that number because it needs to. When you have your pressure set at the correct range for you, it allows the machine to do its job more efficiently by not taking forever to reach the pressure needed, which in turn you AHI numbers should drop. Just give it some time.
Now with the pillows...I find I have to change them often...like every 20 days! They get too soft, cause my nose to itch, and I notice more leaks. Also, if I try to use a worn out one, my AHI goes up. I know that everyone is different.
Reply
#6
(02-11-2015, 06:07 PM)Sleeprider Wrote: The median value is actually the most frequently occurring pressure, not the middle value (mean).

No, I'm sorry, you are wrong. The "mode" is the most frequently occurring value, the "median" is the middle value, and the "mean" is the common "average" obtained by adding up all the data points and dividing that sum by the number of data points.

I looked it up on google just to be sure.
Ed Seedhouse
VA7SDH

I am neither a Doctor, nor any other kind of medical professional.

Actually you know, it is what it isn't.
Reply


#7
Brain fart! That's what I'm stickin' with. Smile
______________________________________________
Organize your SleepyHead Data
Post your SleepyHead Data from Imgur
Robysue's Beginner's Guide to Sleepyhead
Reply
#8
so the median is likely to go up because the mode is forced to a higher value. this likely means OSA related events and occurrences are reduced. this may also result in higher CAs and so net increase in AHI may occur possibly creating a new maximum.
Coffee
Reply
#9
(02-11-2015, 09:58 PM)quiescence at last Wrote: so the median is likely to go up because the mode is forced to a higher value.

Well no. If you increase the top pressure while the bottom remains the same the median (middle value) will go up regardless of what happens to the mode. The mode could be very low so long as it is the most frequent value.
Ed Seedhouse
VA7SDH

I am neither a Doctor, nor any other kind of medical professional.

Actually you know, it is what it isn't.
Reply


#10
(02-11-2015, 10:40 PM)eseedhouse Wrote:
(02-11-2015, 09:58 PM)quiescence at last Wrote: so the median is likely to go up because the mode is forced to a higher value.

Well no. If you increase the top pressure while the bottom remains the same the median (middle value) will go up regardless of what happens to the mode. The mode could be very low so long as it is the most frequent value.

Except we are talking about the max pressure setting going down and the min pressure setting going up. The reduction of the max pressure setting has no effect on the statistics at its current level. The min. pressure setting, however, does have an effect.

Best Regards,

PaytonA
Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  Please Help Getting AirFit P10s to Work For Me (Higher AHIs) Spy Car 16 512 01-02-2017, 04:33 PM
Last Post: Spy Car
  AHI higher with DreamWear Mask Judy1843 1 329 11-29-2016, 08:04 PM
Last Post: sonicboom
Question AHI Higher AFter Switch from Nasal Pillows to Full Mask Sleepypokey 8 639 10-26-2016, 03:07 PM
Last Post: Kadenz
  Question on masks that will handle higher pressures like 27 nanook683 13 1,036 09-21-2016, 07:14 AM
Last Post: nanook683
  Leak Rate Higher/Centrals Higher since New Machine? TheManseHen 1 270 08-28-2016, 08:15 PM
Last Post: PaytonA
  Please HELP! New CPAP user .. 3.5 weeks in .. AHI still avg high 4 - mid 6 range mikeuva123 20 1,387 07-25-2016, 07:48 AM
Last Post: computerbudda
  Lower EPR Higher Hypopneas holden4th 5 530 07-07-2016, 08:36 AM
Last Post: green wings

Forum Jump:

New Posts   Today's Posts




About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.

For any more information, please use our contact form.