Definition for I:E ratio

[jjsjr249]

Hello,

I'm trying to determine what a "good" or "bad" I:E ratio is.  I'm using a ResMed AirCurve 10 machine in CPAP mode.

Is there any information that rates an I:E ratio as "good" or "bad" or "Average"?

Snapshot of today's SleepHead statistics related to post is below:

I:E RatioRatio between Inspiratory and Expiratory time (ratio)
W-Avg: 53.28
0.00
54.00
63.00
100.00
Insp. TimeTime taken to breathe in (Seconds)
W-Avg: 1.52
0.00
1.54
1.74
2.42
Exp. TimeTime taken to breathe out (Seconds)
W-Avg: 2.86
0.00
2.86
3.42
10.00

Thanks in advance,

jjsjr249@gmail.com

[Walla Walla]

No hard or fast rules. Most of the time it's about twice as long on the Expiratory as it is on the Inspiratory. Yours is normal.

[Sleeprider]

First, the I:E ratio is not properly calculated by Sleepyhead for this machine. Sleepyhead is using the formula I/E*100. I have worked with JediMark on this issue and a correction will be issued. The usual way of expressing the I:E ratio is to compare inspiration time to expiration time. Using median values from your data, your inspiratory time is 1.54 and expiratory time is 2.88. 2.88/1.54=1.87, or a ratio of 1 to 1.9 (1:1.9). Your expiration is nearly twice as long as inspiration which is normal. In general, the I:E ration will range from 1:1 to 1:3, meaning normal exhale can be in a range of equal to 3 times the time of inhale. We often see an I:E ratio of less than 1 suggesting a longer inspiration time than expiration. This inverse I:E ratio can occur, but most of the time it is an error in the respiration timing by the CPAP machine. The Philips models are very susceptible to this error, and it's worth looking closely at the flow rate chart to verify.

Going further, your total cycle time is 1.54+2.88=4.42 seconds. So in one minute, you will have 60/4.42 13.57 breaths per minute. I wrote a more complete explanation in the Beginners Guide To Sleepyhead http://www.apneaboard.com/wiki/index.php...ailed_look

[jjsjr249]

Thank you.  This helps a lot!

Jack

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This helped me a lot.  The attachment is also very good.  Browsing I've located answers to 4-5 other questions that I've pondered.

Jack