AHI

[Titrator]

acronym: Apnea Hypopnea Index

AHI (Apnea Hypopnea Index) is the number of apneas and hypopneas per hour. 5-20 mild, 21-50 moderate, above 50 severe

To determine AHI add the total number of Apnea events, plus Hypopnea events and divide by the total number of minutes of actual sleep time, then multiplied by 60.

Example

Apnea + Hypopnea divided by actual sleep time, then multiply by 60

200 Apnea
200 Hypopnea

400 Total Events

420 Actual Sleep time (7 hours)

Divide 400 by 420 =.95 x 60 = 57 AHI (Severe OSA)

[Guest]

The Severity of OSAHS as defined by the American Academy of Sleep Medicine Task Force (1999) is
AHI < 5 Normal
5 =< AHI <15 Mild
15 =< AHI <30 Moderate
30 =< AHI Severe

The above is the most widely used severity definition.
I know that British are using different criteria.
============================================

Medicare coverage:
60-17. CONTINUOUS POSITIVE AIRWAY PRESSURE (CPAP)
Effective for services furnished between and including January 12, 1987 and March 31, 2002:
The diagnosis of OSA requires documentation of at least 30 episodes of apnea, each lasting a minimum of 10 seconds, during 6-7 hours of recorded sleep. The use of CPAP is covered under Medicare when used in adult patients with moderate or severe OSA for whom surgery is a likely alternative to CPAP.

Effective for services furnished on or after April 1, 2002:
The use of CPAP devices are covered under Medicare when ordered and prescribed by the licensed treating physician to be used in adult patients with OSA if either of the following criteria using the Apnea-Hyopopnea Index (AHI) are met:
AHI ≥ 15 events per hour, or
AHI ≥ 5 and ≤ 14 events per hour with documented symptoms of excessive daytime sleepiness, impaired cognition, mood disorders or insomnia, or documented hypertension, ischemic heart disease or history of stroke.
The AHI is equal to the average number of episodes of apnea and hyponea per hour and must be based on a mimimum of 2 hours of sleep recorded by polysomnography using actual recorded hours of sleep (i.e., the AHI may not be extrapolated or projected).

[-SWS]

The above is the most widely used severity definition.
I know that British are using different criteria.

Guest, any idea as to how prevalent deviation happens to be across sleep labs in the U.S. relative to that AHI definition? Is that AHI severity criteria used by slightly more than half of the sleep clinics, by a near consensus, or perhaps somewhere in the middle? I suspect Titrator would have given an AHI severity definition in accordance with the sleep lab he worked in.

I know world-wide AHI standardization is an outstanding issue in sleep medicine. I just don't know how standardized or non-standardized the U.S. happens to be.

[Zees Pleez]

So what is RDI? My report said I had an AHI of 30 events an hour, a supine RDI of 45 events per hours and a REM RDI of 54 events per hour. What's the difference?

I came back and edited to add this after I searched around and found my answer:

The RDI (respiratory disturbance index) includes apneas and hypopneas, and may also include other respiratory disturbances such as snoring arousals, hypoventilation episodes, desaturation events, etc. They are often identical, but depending upon what is scored, the RDI may be larger than the AHI.

[Capri]

I have an average AHI after 2 weeks of nearly 40. I got the ResScan software to accompany my machine which is how I got this number. My doc had my machine set a 7cm and said to come back in 6 months. Is this outrageous or typical?
_________________

Settings: CPAP 10, Ramp 10 @ 4cm, heated humidity, AHI=35

1. Main unit: ResMed S8 Elite, ResMed Humidaire 3i
2. Backup: ResMed S6 Lightweight
3. Mask: ResMed Swift II
4. Backup: NasalAire II
5. Health Tools: ResMed ResScan Data Card, CMS-50E Pulse Oximeter, OneTouch Ultra glucometer, Citrus II spray mask cleaner
6. Software: ResMed ResScan 3.3, OneTouch

[Wulfman]

I have an average AHI after 2 weeks of nearly 40. I got the ResScan software to accompany my machine which is how I got this number. My doc had my machine set a 7cm and said to come back in 6 months.

Is this outrageous or typical?

Your "TREATED" AHI (Apnea/Hypopnea per hour) should be LESS THAN 5.0.
If it's STILL 40 (and this would be PER HOUR....and NOT TOTAL events), then there's something wrong with your therapy.
You either are having massive leaks or your pressure is too low or you're not understanding the software reports.

Why don't you fill in your profile with all of the specific equipment you're using and then start a new "thread" for folks to try to help you out.

Den

[Capri]

My AHI went from nearly 40 to 32 when I corrected the leak issues with my mask. Tomorrow I see the neurologist armed with reports from ResScan and my CMS-50E pulse oximeter.

[rested gal]

come back in 6 months.

Is this outrageous or typical?

Typical, I'm afraid. If you weren't taking control of monitoring your own treatment, and if you hadn't found this message board....well.... looks like you'd have 6 months (at least) of ineffective treatment. And maybe more -- even for the rest of your life -- if all they normally do (if THIS much) at the 6 month visit is check to see if you're using the machine regularly ("compliance") and don't even glance at any detailed data.

"So, how are you feeling?"

"Doc, I still feel lousy."

"Hmmm, well, I see you're using your machine every night. That's good."

"Then why do I not feel any better?"

"This treatment takes time. Keep using your machine and see me again in six more months. We may need to schedule another sleep study then."

[BarryKaraoke]

"So, how are you feeling?"

"Doc, I still feel lousy."

"Hmmm, well, I see you're using your machine every night. That's good."

"Then why do I not feel any better?"

"This treatment takes time. Keep using your machine and see me again in six more months. We may need to schedule another sleep study then."

Which is often unfortunately followed by "I tried CPAP and it didn't work for me."

[Nodzy]

All very interesting, and I will post more about VA methods later on this thread.

But for now:

The VA does one sleep study per patient, as the norm. And I quote in response to my asking multiple times for another asleep study:

"We only do one sleep study. You do not need another. One sleep study is proven adequate for apnea treatment."

"If a doctor thinks you need changes, he or she will prescribe them."

Therapy changes, of course, are based on the VA doctor's whims at the moment, and possibly on or with knowledge of whether the patient professes to use the machine routinely or not. But prescribed changes surely won't be based on up-to-date sleep study data. And likely not even based on machine LCD screen data.

Of course, the VA doctor prescribing the changes in SDB therapy is not board certified in that discipline. And he or she will not confer with a board certified physician before prescribing a change. He or she will probably be the primary for the patient, or maybe just a stand-in doctor on that day who is totally unfamiliar with the patient.

As I see it, that is akin to an automotive general mechanic..... diagnosing and prescribing based on visual examination alone.... to remedy an engine electronics malfunction that causes spontaneous and dangerous acceleration lags, surges, sputtering and backfires.

Ok...so a blindfolded person with a thousand darts may be able to score a bullseye once or twice per thousand tosses. But probably none.

Close counts, right? And "close" is defined as.... how wide a span?

Had I not found this board, and drank heartily of the knowledge and enouragement offered here, I would likely be real close to having my turn on the mortuary slab... or possibly past that event.

I'm done ranting for now... but will post more on this topic.

Nodzy

[sharon1965]

come back in 6 months.

Is this outrageous or typical?

Typical, I'm afraid. If you weren't taking control of monitoring your own treatment, and if you hadn't found this message board....well.... looks like you'd have 6 months (at least) of ineffective treatment. And maybe more -- even for the rest of your life -- if all they normally do (if THIS much) at the 6 month visit is check to see if you're using the machine regularly ("compliance") and don't even glance at any detailed data.

"So, how are you feeling?"

"Doc, I still feel lousy."

"Hmmm, well, I see you're using your machine every night. That's good."

"Then why do I not feel any better?"

"This treatment takes time. Keep using your machine and see me again in six more months. We may need to schedule another sleep study then."

RG
for a minute there i thought you must've been in the room with me for my first check up! my doctor even told me i may have to wait up to a year to see any results
so glad i listened to the folks here and got my treatment on track on my own

[deerslayer]

Nodzy, my experiance has not been the same as u concerning the V A ,Alvin C. York hospital. i was started in early dec. & told to turn in the smart card after 30 days.Fortunately,a week after starting therapy i bumped into this blessed epiphany of a forum & secured the encore,card ,reader before i turned in the V A card. however, un beknownst to me they have already scheduled me for another sleep study this coming oct. frankly, i may just cancel,since i feel i am on top of this thing. i know i can call them any time to discuss treatment ?'s. plus i will probably at one time send in printouts from the encore & let them know i know a small percentage of what they know . anyway i am pretty well blown away that they are spending $ on this old barnicle to begin with...i think the whole thing boils down to taking the steering wheel ourselves & mashing da gas * my 2 cents . tim

[Nodzy]

Nodzy, my experiance has not been the same as u concerning the V A ,Alvin C. York hospital. i was started in early dec. & told to turn in the smart card after 30 days.Fortunately,a week after starting therapy i bumped into this blessed epiphany of a forum & secured the encore,card ,reader before i turned in the V A card. however, un beknownst to me they have already scheduled me for another sleep study this coming oct. frankly, i may just cancel,since i feel i am on top of this thing. i know i can call them any time to discuss treatment ?'s. plus i will probably at one time send in printouts from the encore & let them know i know a small percentage of what they know . anyway i am pretty well blown away that they are spending $ on this old barnicle to begin with...i think the whole thing boils down to taking the steering wheel ourselves & mashing da gas * my 2 cents . tim

Tim,
I'm certainly glad that your experiences were far better then mine. Though, after talking with many other patients at the facility I've found that their stories nearly mirror mine for that particual facility... and many tales-of-woe were far worse.

Of course, there's much more to my experiences with them that would make most people shudder. Good luck, and I hope they do perform to very high standatrds for you... consistently.

Nodzy

[lr visitor]

I don't understand this business about it taking a long time. I felt better the morning after the first time I used a CPAP. (Better enough that I made my own to use until the official one came through.) I vaguely recall that improvements continued for a few days after starting. But I think the double vision while driving went away immediately. On the other hand, I think feeling generally "with it" continued to improve for a month or more. But most of the improvement, I think, was very quick.

[roster]

I don't understand this business about it taking a long time. I felt better the morning after the first time I used a CPAP. (Better enough that I made my own to use until the official one came through.) I vaguely recall that improvements continued for a few days after starting. But I think the double vision while driving went away immediately. On the other hand, I think feeling generally "with it" continued to improve for a month or more. But most of the improvement, I think, was very quick.

So you made your own CPAP?