AHI vs CPAP AHI

What is AHI as it relates to sleep apnea? How accurate is the AHI reported by a CPAP machine? Listen in for my quick answers to these questions!

[georgeetherege]

I'm the worst patient, a retired engineer who must understand every part of any medical process.
You confirmed what I guessed. Since I haven't been able to get to sleep when using my CPAP--haven't used it more than 1-1/2 hours the few times I've tried it, either--AHI figures are meaningess. No sleep while using CPAP... Can't be any "interruptions" to sleep to keep track of.
I will almost certainly declare defeat and return the machine in six weeks when I reach the magic 90 days with virtually no four-hours-a-night usage to report. Experience is the best (and most expensive) teacher-- I should have first consulted an ENT specialist who works with causes of poor sleep and then had the cardiology Sleep Center prescribe a CPAP machine with the proverbial insurance requirement countdown clock attached.

[bradglasgow]

Just got a bipap machine a few weeks ago and your videos have been super helpful! I really appreciate that they're not the typical YouTube video artificially stretched out to 10 minutes in order to hit the algorithm. Thank you!

[earlhaupenthal]

Thanks for going into detail. I have severe osa and with the cpap my readings are around .5. Which is grea. Under alot of stress lately and have readings up to 1.5.
I was shocked to hear that the average person stops breathing 5 times an hour.

[Chiswick-Edward]

I think she was referring to an average reading over a long period. It seems unrealistic to experience life-threatening, intense apnoea for an extended time (months, for example) without occasionally having elevated AHI readings. It doesn’t seem feasible to maintain an average AHI below 10 while experiencing 100 apnoeas in under an hour.

I was also surprised to learn that a pause in breathing for just over 10 seconds qualifies as a breathing event. During the day, this would seem relatively normal. A pause of 15-30 seconds would be more concerning, in my opinion.

Another question I have is why oxygen levels aren’t consistently measured alongside apnoea events. If oxygen levels are low, that clearly indicates a problem, but if they aren’t, then what does it signify?

This initial testing process is confusing to me. I was diagnosed with moderate apnoea (AHI = 28), yet my oxygen levels remained normal (around 94) throughout the night, and I woke up feeling refreshed. I don’t fully understand why a positive diagnosis is given when oxygen levels are stable, and the patient feels well. Having to rely on a machine indefinitely for something like this seems excessive.

[daveroski]

Can you have a low AHI, but have a low oxygen levels? I would think in order to better gauge sleep (gauge correct pressure) having the AHI should include monitoring oxygen..?

[sleuththewild]

You’re not familiar with Oscar? CPAP users can see detailed data whenever they want and read it with Oscar. They can figure out under what conditions they get apnea, how long the apneas last, and whether the pressure is optimal (the doctor defaults of 4-20 on an APAP almost never are), among other things.

[sleuththewild]

An AHI of 10 is okay with a sleep specialist? It's an average! In an 8-hour night, it could mean 80 apneas in one hour, no apneas in the other hours. This would be a SEVERE and life-threatening problem.
Even 5 AHI could be potentially dangerous, in that situation. It would mean you couldn't get breath 40 times in one hour. And if they're long apneas, well, sayonara.