AHI vs. ODI

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
schwawi
Posts: 34
Joined: Sat Jul 11, 2009 9:31 am

AHI vs. ODI

Post by schwawi » Sat Aug 29, 2009 10:21 pm

Hello,

I am currently tracking AHI via my CPAP and ODI via a recording oximiter. I have found that, in some cases, my AHI trends upwards as my ODI trends down with increased pressure. This is almost entirely due to more recorded hypopneas by the CPAP machine. Apneas are almost completely gone.

Has anyone else encountered this? having pretty good Oximeter readings with AHI often over 5 and sometimes not so good Oximeter readings when AHI is less than 5?

Am trying to figure out what is going on here, but suspect that the CPAP machine is not so accurate and maybe sensitive to pressure and/or leaks, causing it to register more hypopneas than actually present. Guessing the oximiter is more accurate (SPO 7500).

If anyone cares to comment, I'd really like to hear it so I can try to sort through this.

Thanks

User avatar
billbolton
Posts: 2162
Joined: Wed Jun 07, 2006 7:46 pm
Location: Sydney, Australia

Re: AHI vs. ODI

Post by billbolton » Sun Aug 30, 2009 1:19 am

schwawi wrote:Am trying to figure out what is going on here....
You may find this article on Nocturnal oximetry for the diagnosis of the sleep apnoea hypopnoea syndrome...

http://thorax.bmj.com/cgi/content/abstract/54/11/968

... and the subsequent citation list for it in following articles, of interest.

Cheers,

Bill

_________________
MachineMask
Additional Comments: CMS 60C Pulse Oximeter, ResScan 5.6