Help Interpreting Oximiter Results

[schwawi]

Hi everyone,

I recently purchased and am using an SPO 7500 Oximeter. While I am happy with the product and software, I am having difficulty interpreting the results and was hoping that someone in the forum more knowledgeable might be able to provide an informal opinion.

See my results from last night below.

My CPAP was set at 8.6 and my AHI for the evening came through as 6.7, AI = 0.6, HI = 6.1 This is a pretty typical night for me, though my AHI often comes in below 5.0.

On thing that puzzles me is I see 52 Desats total, yet that was more than the total number of events recorded by my machine.

Can anyone provide a perspective here? I'd really appreciate it.

Thanks

[twokatmew]

I have the same oximeter and used it nightly when I first got it. I haven't found a lot of correlation between desats and events. Some nights my AHI is better and the ODI is worse. Other nights my AHI is bad and the ODI looks very good. Still other nights AHI and ODI are similar. You can have events w/o desaturating, and apparently I can desaturate w/o having an event. I've found that looking at individual nights aren't that much help unless I'm troubleshooting a particular problem. I tend to get more useful information looking at the longer-term trends for both AHI and ODI. How many nights have you used your oximeter? How do the trends compare?

Sorry I can't be more helpful. Perhaps someone more knowledgeable can jump in here.

[schwawi]

Thanks for your reply. I've only used it for a few nights and have noticed ther same lack of correlation you refer to. I'll keep using it to tryo to sort it out, but if anyone else has perspective, it would really be helpful.

Arent desaturations all that really matter here? if I have an "event" without desaturating, is it really an event that matters? Conversely, if I have a desaturation that doesnt get counted as an event, which must have happened here since my desats are higher than my events, is my machine really reliably picking up all real events? or is it normal to have some level of desaturation regardless of apnea related events?

[Arizona-Willie]

I like the way that oximeter does the reports. It shows you the time you were in desat during the night. I have to plug my time percentage into a spreadsheet and figure it for myself.

Your observation that AHI and desats are not in synch is correct. I frequently see nights where the AHI is pretty good but desats are no so good. And the other way too .. I have bad AHI and relatively good desats.

Most of the time your AHI and desats probably will be somewhat correlated but not always that's for sure.

I trust the oximeter reading more than the cpap AHI measurements. All the different machines use different algorithms for calculating stuff but O2 saturation is O2 saturation ... no room for different ways to figure it.

I'm jealous of your reading... wish my O2 level was that high. Here's a bit of the data from my report on last night. Last night was pretty good ... only 2.1 minutes below 90% O2 sat. But I was below 95% 9l.6% of the time ... almost all night.

Friday night AHI = 3.7

Basal Sp02(%) 92.8

Timemin<88% 0.0

Events<88% 1

MinimumSpO2(%) 87

Avg. LowSpO2(%) 89.5

Avg.LowSpO2<88% 87.0

Avg Pulse Rate(bpm) 55.3
Low Pulse Rate(bpm) 47

[schwawi]

I'm jealous of your reading... wish my O2 level was that high. Here's a bit of the data from my report on last night. Last night was pretty good ... only 2.1 minutes below 90% O2 sat. But I was below 95% 9l.6% of the time ... almost all night.

Friday night AHI = 3.7

Basal Sp02(%) 92.8

Timemin<88% 0.0

Events<88% 1

MinimumSpO2(%) 87

Avg. LowSpO2(%) 89.5

Avg.LowSpO2<88% 87.0

Avg Pulse Rate(bpm) 55.3
Low Pulse Rate(bpm) 47

Thanks for the perspective. how many total desat events did you have? have you tried increasing your pressure to reduce # of desats?

[ozij]

Same oximeter, same discrepancies.

I try to have my pressure where my ODI is on the lower side -- I feel the difference.

O.

[schwawi]

Same oximeter, same discrepancies.

I try to have my pressure where my ODI is on the lower side -- I feel the difference.

O.

Thanks very much,

Can you tell me how you define "lower side?" What number or range do you target? and is the pressure you are using to get there significantly different from your last titration study? I look forward to your reply next time you check-in.