ahi numbers

Paul B · Post by **Paul B** » Sun Jan 02, 2005 8:15 pm

It's more like CPAP 11 on inhale and CPAP 7 on exhale.

Guest · Post by **Guest** » Sun Jan 02, 2005 8:29 pm

Paul B wrote:It's more like CPAP 11 on inhale and CPAP 7 on exhale.

I tried that! I set up two CPAP machines, two hoses, and two masks on my night stand. Didn't get a wink of sleep that night, either---switching back and forth on each breath!

And they call BiLevel "sleep therapy"???

BetterBreathinBob · Post by **BetterBreathinBob** » Sun Jan 02, 2005 8:46 pm

Dear Wading, that's correct. The object for CPAP is to splint or stabilize the inside of the airway to prevent collaspe at end exhalation. The problem occurs is when the pressures get into the higher ranges, like above 14-16, it becomes hard to exhale against the resistance, but it's the resistance that is required to keep the airway open.
It was the engineers who came up with the Bipaps in response to so many compliants about the CPAP machines at high pressures. By giving a boost during inhalation the patient is supposed to be able to tolerate the high end ehalation pressure.
I think that Bipap is uncomfortable to use. Apap is the best way to go.

Good luck and good night everyone. My mask is calling me!

Bob

steveinhouston · Post by **steveinhouston** » Sun Jan 02, 2005 9:08 pm

Thanks for all the responses. As it turns out, I had two nights at the sleep lab. The first night, I slept very little, but enough so that the technicians determined that I had 63 events per hour without treatment. Half way through the night, they put me on a BiPAP with a nasal mask, but I barely slept at all after that. The sleep doc said that I did not sleep enough with the mask on for the technicians to tritrate properly. I mentioned to the doctor that I had difficulty sleeping with the nasal mask because I have always been a "mouth breather"; I had severe allergies and asthma as a child (which I have since out grown) and thus learned to breath through my mouth. He recommended that I use a full face mask for the second night at the lab, and the lab technician fitted me with an Ultra Mirage full face mask for the second night.

The second night at lab I was on the BiPAP the entire night, and I slept 75% of the time; the sleep doc said that almost all of the apnea events were eliminated with the BiPAP set up with an IPAP (inspiratory positive airway pressure) of 11 and an EPAP (expiratory positive airway pressure) of 7, so that was what he prescribed.

After three nights on the BiPAP, I am feeling much better, so it appears to be working, even with the leaky mask. Thanks again for the help.

wading thru the muck! · Post by **wading thru the muck!** » Sun Jan 02, 2005 9:20 pm

Hi steveinhouston,

Do you have another respiatory condition that would make it difficult for you to exhale against 7cm pressure. In my experience after a half hour breathing 6cm I can't even tell it's on. Do you own this biPAP unit? If not and you ultimately will be buying a unit, I would consider an autoPAP.

steveindelavan

wading thru the muck! · Post by **wading thru the muck!** » Sun Jan 02, 2005 9:31 pm

BetterBreathinBob,

Thanks for the replies. So essentialy the biPAP blows you up so that the extra pressure helps with the exhalation against a high pressure. That's thinking outside of the box! My patient is having trouble exhaling against 16cm cpap... how 'bout we invent a machine that blows him up like a balloon so that exhalation against 16cm won't feel so bad.

Makes me like my autopap even better.

steveinhouston · Post by **steveinhouston** » Sun Jan 02, 2005 9:45 pm

Wading:

I don't have any respiratory problems, and I haven't had any problems exhaling against the pressure of the BiPAP. I suspect that the sleep doc prescribed the BiPAP only because the sleep lab I went to evidently uses BiPAPS rather than CPAPs. The insurance company is renting the BiPAP for a year, so, at my next appointment, I will mention to the sleep doc the possiblity of using an autopap. I know that an autopap would make it easier to avoid having to spend more time at the sleep lab for pressure adjustments.

wading thru the muck! · Post by **wading thru the muck!** » Sun Jan 02, 2005 9:55 pm

Steve,

If things are going well after a month I would consider buying an autopap right away. You (or your insurance) can buy and autopap for a small fraction of the cost of renting for a year. If and when you get one, get software with it to monitor how things are working for you.

Steve

Titrator · Post by **Titrator** » Sun Jan 02, 2005 10:00 pm

The EPAP pressure is where apnea is cleared. The IPAP pressure is where flow limitation, hypopnea, and snore are cleared.

The cpap pressure that is titrated in the lab is the higher of the bipap numbers, hence 11 over 7 would mean that your cpap pressure is actually 11cm.

Ted

wading thru the muck! · Post by **wading thru the muck!** » Sun Jan 02, 2005 10:08 pm

Thanks Ted!

I'm back to confused

This is what I originally thought. Is there some professional disagreement on this? I think BetterBreathinBob is also a sleep proffesional and seems to disagree with you.

It always amazes me when these cut & dry topics seem to bring up so much disagreement.

Wader

rested gal · Post by **rested gal** » Sun Jan 02, 2005 10:57 pm

From what little I know or understand - acquired mainly from reading the message boards, including lurk-reading binarysleep.com's board (message board for sleep techs), I think Ted's (Titrator) explanation nails it. I'm not a health care professional, though - just an avid reader of info about this kind of treatment for a disorder.

Disagreements may be a matter of semantics sometimes, but I'd think a bipap prescription of 11 for inhalation and 7 for exhalation means that a patient would have been given a prescribed pressure of 11 if he/she were to be put on straight cpap. 11 being the titrated pressure to get rid of all sleep disrupting events in that case. Just as Ted said.

-SWS · Post by **-SWS** » Sun Jan 02, 2005 11:01 pm

Titrator wrote:The EPAP pressure is where apnea is cleared. The IPAP pressure is where flow limitation, hypopnea, and snore are cleared.

I think the way Ted beautifully described it in the past is something like: heavy apneic obstructions can start immediately after expiration and just before inspiration---while EPAP machine pressure is still maintained.

So if I followed Ted's earlier explanation flow limitation, hypopnea, and snore are all "light" enough obstructions that they tend to manifest only during inspiration. They are therefore cleared exclusively by a BiLevel machine's IPAP pressure. HEAVY apneas can literally "start hangin' low" as soon at the very tail end of expiration. These apneas would be cleared initially by EPAP, then IPAP would continue the necessary thrust.

Adding to this (please correct me if I'm wrong, Ted) apneas that are not quite so "heavy" by the way of hanging tissue mass can actually begin to manifest well into the inspiration phase (and thus treated exclusively by IPAP as with the other three lesser obstruction types mentioned).

Titrator · Post by **Titrator** » Sun Jan 02, 2005 11:51 pm

SWS, you are correct. But, if your airway is open because the EPAP pressure is high enough, the rest will take a higher pressure.

While titrating distinctly for a bilevel, I would raise both IPAP and EPAP at the same time, basically like a regular cpap. When the flat lining apnea stopped, I would leave EPAP on that pressure. Take into concideration that the sats may be really bad. That doesn't figure into the equation just yet.

I would raise the IPAP until I had a completely clear airway and the patrent is no longer desaturating. You can easitly see the patient has settled down and begins to maintain a steady heart rate, respiratory rate and smooth inspitory and expitory flow.

With a bilevel, you must maintain at least a 4cm split between IPAP and EPAP. My particular bilevel pressure is 19 over 13, which is 5cm. Older bilevel machines would not split more than 4cm, but todays high tech units easly split over 4cm.

If you get someone up into the over 20cm range on IPAP and he/she is still desaturating, you add suplimental O2, starting with 2L and not moving past 4L. If that doesn't do it, you call the doctor in the middle of the night and alert them to the situation and ask how they would like you to proceed.

They may ask you to keep the patient so they can speak to them in the morning. Unfortunately, some people will have to have surgery or a trach or they are in serious trouble. I have heard of doctor's telling the patient to lose weight or they will be trached.

Some nights it is like riding a roller coaster trying to pull someone's sats up into range. Those are the nights you really work for your paycheck.

Ted

PS sorry if this is gibberish, it is late and i am tired.

-SWS · Post by **-SWS** » Mon Jan 03, 2005 12:00 am

That's a pretty darn good explanation for me, Ted! Thanks.

wading thru the muck! · Post by **wading thru the muck!** » Mon Jan 03, 2005 4:48 am

Thanks Ted,

Your explaination makes sense to me. Essentially the EPAP is set at the pressure where the apnea begins to clear and the IPAP is set where the airway is normalized. Kind of like a blood pressure reading.

I appreciate the technical explaination. For those of us concerned with where we fit into the scheme of treatment options this info is invaluable.

I bet that "lose weight or get trached" threat gets 'em going.

Wader

ahi numbers

11/7

Bipap

ahi numbers

ahi numbers

Titrating

Machine