Maintenance of Wakefulness Test--Important Charts

5aces wrote:Today I met with the Respirologist at the sleep clinic to review the MWT results.

Not the "fait accompli" I had anticipated.

Another doctor had interpreted the results from study and had not signed off on the assessment,pending the respirologists review.

Indeed I did fall asleep for 2 minutes during the first session,8 seconds for the second session and only brief seconds for the third and fourth tests.
Both doctors must reconvene to interpret these results,the interpreting physician felt the small periods of sleep were of no great consequence,whereas the respirologist wanted further analysis.

Not unexpected though,as I had a busy night of re-titration prior to the daytime screening.

The pressure was varied from 8 to 13 cmh20,with 10 being the optimum for preventing AI's.

Oddly,(and the subject of further scrutiny)were the numbers that showed a pressure of 13 afforded the most REM sleep time,also the produced the highest AHI level.

The plan for now is:

1) both doctors will confer on the sleep study numbers and assess.

2)a ResMed Autopap is to be provided for home use,to capture 7 days detailed data at an 8 - 13 cmh20 variable setting.

3)follow up in three weeks to further assess and advise.

On a side note I had a few kidney stone attacks last week,they were just plain off the hook,my first and hopefully last!

Likely from inactivity following the sinus surgery in April,what can you do if you've spent too much time in bed?

I still don't "get" the screening coming right after a titration. After a night of monitored PAP, yeah. But not titration.

I see the importance of titrating for supine REM and all, but I wonder how often a lower pressure might have allowed just as much REM just as well. And I wonder if sometimes REM is going to have a jump in AHI regardless.

I had a kidney stone a few months ago. Also my first. Hopefully my last. I think PAP therapy changes the way our bodies handle fluids to the point that people on PAP should drink beyond their thirst for a while until the body gets used to everything. I now understand that it isn't so much a matter of how much water I drink, but the amount I urinate and how clear it is.

The stone changed my pain threshold, though. I am now slightly less wimpy. I had a medical test a few weeks later that required a peripheral IV line, and it took the nurse 4 attempts at different locations to get it right. She seemed very embarrassed and distrubed by the "torture" she was submitting me to. I told her not to worry--I didn't really mind it at all. I used to find that kind of thing very painful, but I barely felt it in comparison to the kidney stone.

Thanks for keeping us updated, 5aces.

jnk wrote:

I had a kidney stone a few months ago....

The stone changed my pain threshold, though. I am now slightly less wimpy.

bro, knowing how severe your OSA has been and for how long, no one would consider you 'wimpy'. in fact, you might just be one of the toughest men i know!

either way, i bet even chuck norris would well up at least 1 tear if he ever had a kidney stone.

5aces wrote: @Blackspinner:
I thought about what you said.
At best,I could only surmise that they were trying to capture what would be a "worst case senario"-one that could easily happen on any given night at home.
My state of wakefulness at that point could easily be transferred into a real life situation and for the sake of safety,the results should matter.

Yes but most people have "bad" nights at some time - the "regular" people are not kept over nite, awakened several times and then tested for wakefulness.

Today I picked up the Titration Report,MWT Report (very sparse!) and CPAP Interpretation Report.

-Titration Analysis

-Titration Chart


-Titration Graphs


MWT Chart


Physican Summary

After one year of cpap,I am still saddled with swollen sinuses (vasomotor rhinitis) during cpap use,obviously impacting the results.
So I will try the Auto machine and hope for the best.

Since you have vasomotor rhinitis I am assuming you do use an integrated heated humidifier and that you adjust the humidity as needed so need to ask if you have tried other than nasal pillows masks? If necessary I would go thru a dozen - or more - nasal cushions and even a dozen full face masks if needed to find a mask other than a nasal pillows style. I would expect a nasal cushion or full face to be easier on the sinuses. The air pressure is so much more direct w/nasal pillows and therefore more "irritating".

Have you been checked for allergies? Even food allergies can cause vasomotor rhinitis, not necessarily just inhaled allergens.

The charts were pretty small for these ole eyes to struggle with but I did notice 20 Central Apneas, 105 Hypopneas and only one Obstructive Apnea in the first chart. If that holds true thru the rest of the study(s) I'd be inclined to say that maybe you are NOT on the CORRECT device for your needs.

Thanks for the comeback.
Resampled the charts and added 500 pixels,now they are set for old eyes!

Yes,I have been to an allergist and tested negative.
Vasomotor Rhinitis,as it was explained to me,is the "non allergic" form of rhinitis.
Basically the 'unknown' cause of swollen sinus lining,could be any number of stimuli that induces the symptom.

I have a number of masks and cushions and am now onto the machine aspect.
Overbudgeted for all the comfort and convenience cpap items and am one weary shopper,as you know this puts a dirty dent into the pocketbook.

I have also tried all levels of humidity around the dial and have the Heated Cpap Tube so rainout is no longer an issue.
I even spied a new older model F&P HC 100 stand alone humidifier and was close to buying it (based on dsm's review that it heats very hot and can really put out the moisture!) but I didn't want cpap buyer's remorse once again...(or so soon anyway)

Again,appreciate the advice but I really have tried to cover all the obvious to improve the sleep efficiency and I agree with you that the machine should be the focus now and the central sleep apneas investigated further (disconcerting as they are).

I'd still be inclined to suspect nasal pillows as a cause or aggravation of the vasomotor rhinitis. A nasal cushion would produce less direct air pressure and a full face mask even less direct air pressure to aggravate the sinuses and nasal cavities. Maybe investigate the Resmed Adapt SV ENHANCED. Be sure it is the Enhanced.

Well,lately I have been using the Activa LT mask,even though I prefer the Swift LT.

The more I read about central sleep apnea the more perplexing this becomes.
Over a year ago,the diagnosis was Severe Obstructive SA.
I had sinus surgery in April of this year and was breathing easier until the end of June,when I had a terrible sinus infection once again,verifying a continuing chronic sinusitis condition as well (bleh).
Now that the nasal obstructions have been addressed,it is unbelievable that a central sleep apnea condition would now prevail.
Does the recent titration showing more Central Apneas justify pointing in that direction?
Oddly I just had two kidney stone attacks and kidney failure is linked to central sleep apnea...bizarre!

I looked on the ResMed site at their Vpap Adapt SV but no sign of an Enhanced model.

What are the added features?

5aces wrote:Does the recent titration showing more Central Apneas justify pointing in that direction?

Well, I'm no pro (which is my way of saying I got no bidness sayin' what I'm about to say), but I wonder if the sleep-onset "centrals" and stage-shift "centrals" were filtered out or if they were left in.

I think it would be worth asking the sleep doc if those centrals were/are significant. They may not be. But it doesn't hurt to ask, right?

WhiteBeard at apneasupport.com can best explain the differences between the Adapt SV and the Adapt SV Enchanced. He was on the former and was switched to the latter and it has done GREAT for him. I "think" one of the additional features of the Enhanced is full data capability. He's a great guy and more than happy to answer questions and help people out when he can.

Thanks for the lead.Enhanced = $200 more...
White Beard did in fact answer my very question on Oct.07.09 in the ApneaSupport Forum:

"The ResMed VPAP Adapt SV Enhanced came out last year, I thought it replaced all the old VPAP ASV machines.
The Enhanced has a higher output capacity 25 versus I think 20 on the other but I am not sure about that.
Anyway the biggest improvement was that with the enhanced you can see your AHI and AI on the panel screen, and you could not get that information from the older model!
That right there is worth alot, as then you can monitor you progress with using it, without that data available you would never know if your therapy was working.
With the enhanced you can read off the top screen panel every morning your Leak rate, AHI, AI, Average Pressure, VT, Resp Rate, MV, Used, Usage and Mask fit.
Out of habit every morning I check and write down this data.
I also have the ResLink and data card with the Nonin Pulse-Ox that connects onto it, so every week or so, I down load it to my computer.
The detailed data gets my pulse,O2 Sat and all the rest of the data minute by minute all night long for all the nights!
But the ResLink and Card and Card reader and the Pulse-Ox cost me a pretty penny!
I had to pay for that out of pocket! you can alway PM me if you have any questions.Good Luck to You .....White Beard"

jnk wrote:

5aces wrote:Does the recent titration showing more Central Apneas justify pointing in that direction?

I think it would be worth asking the sleep doc if those centrals were/are significant. They may not be. But it doesn't hurt to ask, right?

I agree about discussing that with the sleep doctor.

Those may be considered just "a handful" of centrals. And/or they might have been "normal" centrals for what was going on at the time they appeared.

Thank you,R.G.

As with most specialist doctors,we never seem to have enough time to cover all our concerns during the alloted appointment time.
My wonderful Respirologist really did not have a proper chance to review the study results either and we both glanced over
the charts at the same time.
Now that I have picked up a set of copies,I am naturally eager to adjust the plan so I can finally get some better results.
Tough not to put the cart before the horse,as I am not booked to be seen for another month!
For now,my DME has been sent an order from the clinic (he called me at home today,on his day off!) to set me up with an Auto Machine and ResLInk to capture 7 days worth of data.
I'll get my answers at the follow up in a month.

jnk wrote:I still don't "get" the screening coming right after a titration. After a night of monitored PAP, yeah. But not titration.

I agree. I don't get that either, Jeff.

A titration that is letting events happen (and cause arousals) during the first pressures tried... that's not going to be as good a night's sleep as a night of CPAP at an effective pressure all night would be.

Interestingly, several experienced sleep techs posting on a forum for sleep professionals wrote that a PSG doesn't have to be conducted the night before a MWT (Maintenance of Wakefulness Test) will be done during the day:

One (RPSGT and manager of an accredited sleep center) wrote:
"The AASM Practice Parameter (box #2) for conducting the MWT makes it -EXPLICITLY CLEAR - that a prior night NPSG is not needed, necessary, recommended nor required before conducting an MWT.

Why is your doctor requiring patients to undergo an NPSG before the MWT?"

And he posted a link to the American Academy of Sleep Medicine's
"MSLT MWT Practice Parameter.pdf"
http://www.aasmnet.org/Resources/Practi ... PP_MSLTMWT. (take this space out) pdf

My note:
(MSLT = "Multiple Sleep Latency Test")
(MWT = "Maintenance of Wakefulness Test")

Another (an admin of the tech's forum) wrote:
"yeah...what __ said: No PSG prior to MWT."

Another (a "senior member) wrote:
"Does not require a Poly the night before."

The "MSLT MWT Practice Parameter.pdf" published in SLEEP, Vol. 28, No. 1, 2005 contained this:

Factors which do not support routine performance of
polysomnography prior to the MWT include the following:
1) studies that report normative data or patient data rarely provide
total sleep time results for analysis, 2) there is no information
about whether the MWT is more or less useful from a clinical
standpoint when prior sleep time is reported, 3) the primary purpose
of the MWT is to document ability to remain awake following
intervention and this issue can be addressed using mean
sleep latency values without knowing the total sleep time, and 4)
polysomnography is relatively expensive.
Thus, performance of polysomnography immediately prior to
the MWT is optional, and the decision should be made by the
sleep clinician based upon clinical circumstances. If the MWT is
performed without polysomnography and results indicate inability
to maintain wakefulness, the sleep clinician may have uncertainty
about the cause of the subject’s sleepiness. In this situation
further evaluation, possibly including polysomnography, is necessary
to determine the reason for inability to maintain wakefulness.


If I were already on CPAP therapy at home, I don't think I'd want my (hopefully effective) CPAP treatment routine changed the night before going in for a MLT (Maintenance of Wakefulness Test.) I certainly wouldn't want to have just undergone a PSG titration that spent a lot of the night at pressures lower than were later found to be "therapeutic" for me.

Sounds to me like they put the cart before the horse, 5aces, by making you go through a new titration the night before the MWT.

If a person fails the MWT, I'd think then it's time to have a full diagnostic PSG and titration...preferably on two separate nights. One night to acquire diagnostic data all night. And a second night to do a thorough all-night titration like the one they performed. However, using the night before the MWT for a titration night.... I don't think that's such a good idea.

But hey, I'm not anything in the sleep profession or health care fields, so...I dunno.

Two years ago I had a sleep study and obtained a CPAP to try to control my snoring. I use it routnely and have no more snoring complaints from my family.

The study and results were reported to the Coast Guard as part of my maritime license renewal. They now want me to take a Multiple Sleep Latency Test or a Maintenance of Wakefulness Test as a condition for my license renewal. The local sleep clinic says the test with the required Polysomnography (required by the clinit, not the USCG) will cost me about $3k.

The general attitude is who cares about the money, it is from the insurance. Not so simple. While $3,000 is a lot of money, it is below my deductable.

Question: Is there anything I can suggest to the Coast Guard other than the MWT or MSLT?

Is the test of any health value to me? I sleep OK, don't snore, don't doze off except in front of late night booring TV occasionally, and don't thik the test will reveal any conditions that need correcting.

Thank you for the advice. /Stu