How can Sleep Lab determine pressure when I hardly slept?

[Skodobah]

Just curious... I was thinking back to Jan. 2006 when I had my sleep study. I slept for one hour, after which they woke me to put on the cpap gear. I did not sleep the rest of the night, and they kicked me out at 4:30 a.m.! How in the heck, then, could they have determined that I need a pressure of 13? Has anyone else has a sleep study wherein they did not sleep once the mask was on, and the techs were playing with the pressure? I think I need to get another sleep study.

- Julie (Sko)

BTW - I swapped the Remstar twice for a new one and it still whistles! I give up.

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[bdp522]

I didn't think that I slept at my titration study, but they still said I needed a pressure of 7. After 3 months of compliance the machine became mine. I switched to auto and with the help of the wonderful people here, I retitrated myself to 9.5. If I had not found cpaptalk I would have stayed at a pressure of 7 and given up on this therapy a long time ago. I am 100% compliant, have AHI normally under 0.5 and feel great!!

Thanks Guys!!!

Brenda

[Skodobah]

Yeah, this place is the best for information and help. We're all in it together, and it's a great community to belong to.

I think my pressure should be lower. In fact, I lowered it to 11 and have found this to be good for me, allowing for more compliance. At 13 I was blown out of the water and could never have tolerated it.

- Julie

[Goofproof]

It's quite possible you were a victim of the old hat trick, when in doubt pull a number, out of the hat. The avg. pressure needed for treatment is about 10 cm, so at 13 cm they have the odds covered, so what if it's too high, it not like they are going to have Centrals or the discomfort of using more pressure than is needed. Jim

[Guest]

How do you know you didnt sleep?

[Goofproof]

The sleep test would confirm whether you slept and how long in each stage, but the patients seldom get a copy of the study so they can say whatever they want. They are the judge, jailer and jury, we are the prisoners. Jim

If we let them do it.

[Guest]

The sleep test would confirm whether you slept and how long in each stage, but the patients seldom get a copy of the study so they can say whatever they want. They are the judge, jailer and jury, we are the prisoners. Jim

If we let them do it.

So you think people regularly falsify medical documents to say someone slept when they didnt?

[sleepyWI]

I did not think I slept either but my sleep study showed that I had only Stage 1 and Stage 2 sleep which are also often associated with some degree of conciousness. You might very well have slept..;.just not deeply. Ask for a copy of your sleep study.

[TWolf]

When I went for my titration I was fairly certain that I hadn't slept either. I had never worn an interface before and honestly didn't know what to expect. The first one made an annoying clicking and thunking sound when I breathed. They changed it and the second one leaked like crazy. All that on top of sleeping in a spider web of wires in a strange room. Good night, sleep well!!! Right. At about 3:30am I seriously thought about getting up and leaving.

When I went to my doctor he went over the results and showed me the graphs. Turns out I did sleep. I had been there for eight hours and slept for four. Of the four a couple were deep and they were able to titrate. I'm at a pressure of 8. It helps to look at the results of the study.

TWolf

[Ric]

How can Sleep Lab determine pressure when I hardly slept?

Statistically speaking, THEY CAN'T

Looking over my data for the past 16 months (wooohooooh!) and looking at the 90% pressure curve, (same one they use for the titration) I can see that, depending on which night I might have had a sleep study, my oh-so-sacred "titration pressure" would have been anywhere between 7 and 15, pretty much at random. Whether or not you slept, it is still a...

DART GAME !



What's your pressure? Throw a dart. Your pressure doesn't seem to be working? Throw another dart!
That's why I believe EVERYBODY deserves a multi-night study with a data-recording auto-titrating xPAP device. Even if you learn that your pressure is a nearly constant night after night after night (that is the working assumption of a one-night titration study), you deserve an objective answer to the question. It can't be done in a one-night sleep study.

Better yet, I believe the time has come that an APAP should be the standard issue for EVERYBODY. In the (unlikely) event that a single pressure will suffice, the APAP can function perfectly as a CPAP.

BTW, my sleep study titration pressure was an amazingly low 7, which I have subsequently recorded on only a scant few nights in the past 16 months. If I were given a straight CPAP set on 7 I would have thrown the thing out the window long ago and never gone back. Which in fact is what about half the people who start CPAP therapy actually do. Which is why the long term compliance rate remains a dismal <50%. In the past several months my "90% pressure" has stayed mostly in the range of 8-13, most commonly about 11. In the summer months my most common titration value (statistically the "mode") is around 9, for reasons I can't explain exactly. Point being, pressures drift all over the map, from night to night, seasonally, and apparently at random. The idea of a constant "90% titration pressure" that is stable (like your height, temperature, visual acuity, gender, etc.) is absurd. The titration pressure has got to be one of the mostly widely varying parameters one can imagine. That, based on looking at many multi-night data recordings from people who use APAP and record their data. For the record, I have seen one recording, a three-week interval (a friend of mine) whose 90% pressure was a steady 11cm except for 2 nights. (AMAZING!) That is exceptional, they do exist.

I think I need to get another sleep study.

Beg, borrow, steal, rent, (whatever) an APAP, do your own sleep study titration. That's what many of the sleep labs use anyway. And who can sleep "normally" in a sleep lab anywaaaaaaaayz?

-Ric

[gasp]

I also wondered how they could diagnose me as having severe OSA when they had me where I couldn't comfortably sleep on my sides and had to sleep mostly on my back. Of course I have severe if sleeping on my back - my airway is mostly closed. That's one sure way to get an OSA diagnosis.

I too have to wonder when I do my titration if I will get a recommendation for too high a pressure as it will take a force gale wind to open up my airway if I'm sleeping on my back

With all the chat in this thread, I'm feeling a bit more urgent to get the titration and equipment.

When I do get it - and I WILL get it - what do I need to purchase to use the machine during a power outage? This year alone We were without power for over 10 days.

[Wulfman]

The sleep test would confirm whether you slept and how long in each stage, but the patients seldom get a copy of the study so they can say whatever they want. They are the judge, jailer and jury, we are the prisoners. Jim

If we let them do it.

So you think people regularly falsify medical documents to say someone slept when they didnt?

They don't necessarily have to "falsify" the documents, but they can (and DO) prescribe whatever pressure they damn well feel like. My titration stopped at 16, but my sleep doctor wrote 18 cm. on my prescription.

Splain THAT one to me......

Den

[Guest]

- what do I need to purchase to use the machine during a power outage? This year alone We were without power for over 10 days.

Your machine will run off a car battery, either by getting (or making) a cigarette lighter cord or by clipping straight to the battery.
If you click on the picture of your own machine at the bottom of your post, you can follow the links there to the available accessories.
Also available is a Respironics branded battery, if you don't want to plug into your car battery.
As far as I know, ALL the battery options are for your CPAP machine only, none will drive your Humidifier. For that you'd need a bit more power, as heat needs power. Best choice there would be either a small generator or more/bigger batteries connected to an AC inverter.
Probably easier to just go without heated humidifier on the no-power nights.

Side Note: The documents for the cigarette lighter cord specify to only use the cord when the car is not running. The voltage is higher when the car is running, and that MAY cause a problem with your unit.

Have Fun,
LyleHaze

[Goofproof]

- what do I need to purchase to use the machine during a power outage? This year alone We were without power for over 10 days.

Your machine will run off a car battery, either by getting (or making) a cigarette lighter cord or by clipping straight to the battery.
If you click on the picture of your own machine at the bottom of your post, you can follow the links there to the available accessories.
Also available is a Respironics branded battery, if you don't want to plug into your car battery.
As far as I know, ALL the battery options are for your CPAP machine only, none will drive your Humidifier. For that you'd need a bit more power, as heat needs power. Best choice there would be either a small generator or more/bigger batteries connected to an AC inverter.
Probably easier to just go without heated humidifier on the no-power nights.

Side Note: The documents for the cigarette lighter cord specify to only use the cord when the car is not running. The voltage is higher when the car is running, and that MAY cause a problem with your unit.

Have Fun,
LyleHaze

A good sized Deep cycle battery will drive the XPAP 3 or more nights, as far as the HH, using is as passover only works fine, Den and I do this all the time, as cooler works better for us. Jim

[arthuranxious]

I had the same issue, I didn't sleep any normal sleep when titrated, had a couple of hours of strange painful gasping semi-sleep. When I began to panic after 3 hours of lying wide awake, thinking just what you expressed: "If I don't sleep, they won't be able to titrate me." So I sat up waiting for the tech to come so I could ask for a sleeping pill. No-one came (they get paid to sit up and watch all night). So as I got moer panicky, I began to scream and beg for someone to come, eventually someone came, they asked me which sleeping meds I usually take. I said I never took one in my life, because I was never unable to sleep until you made me freeze and buckled the mask on so I tight that my nose aches! SO he said, "i'll call a supervisor" The supervisor said "You were sleeping beautifully until a few minutes ago, just be quiet and go back to sleep."
One of the things which bothered me most was they claim that I have misperceptions of sleep, and that this a proof that I also have narcolepsy. I have started to wonder if what I call half-awake when I still hear noises and know what is going on is defined by them clinically as sleep. Or am I really suffering from chronic mispercepetions of sleep...
I have started to lose trust in all my perceptions, period. That is one of the worst aspects of being diagnosed with OSA and possibly narcolepsy (my doctor thinks I don't have it, the sleep lab says I probably do).