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Flow Rate [mine too shallow?] - Printable Version

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Flow Rate [mine too shallow?] - trance - 07-14-2018

[attachment=7334][attachment=7335][attachment=7336][attachment=7337]
My flow rate often looks shallow (if that is the right term?)


RE: Flow Rate [mine too shallow?] - tedvpap - 07-15-2018

I compared your data (Flow Rate, Respiratory Rate, Tidal Volume) to my sister's (also at a low pressure), and it looks similar.


RE: Flow Rate [mine too shallow?] - DeepBreathing - 07-15-2018

Are you asking about the actual flow rate or the way it appears on the graph? You can adjust the appearance on the graph by right-clicking on the words "Flow rate" on the left of the chart, then select "Autofit". Alternatively select "Override" and type in a number of your choice (eg 50). This will increase the size of the trace on the chart.

Looking at your numbers, the tidal volume does look a bit on the low side, with values between 300 and 360. Taken together with the number of oxygen saturation drops this could indicate that your breathing is too shallow and you need to make some adjustments. First I'd modify the SpO2 chart to read 80 - 100 (same technique as described above). Then increase your max and min pressures by about 3cm and turn on EPR and set it to 3. If I'm right, this should greatly improve your tidal volume and reduce the desats. On the other hand, it might induce some central apneas, in which case you'll need to do a trade-off to minimise centrals and maximise your oxygen uptake.

I'm hoping Sleeprider will chime in here as he has more experience with this type of fine tuning.


RE: Flow Rate [mine too shallow?] - Sleeprider - 07-15-2018

If you want to increase your tidal volume a bit, and reduce the flow limitation (flat tops on inspiration curve) then using EPR might help. This lowers pressure during exhale. The difference in pressure between inhale and exhale can make breathing more comfortable, and the pressure-assist can help improve volume and reduce flow limitations. The only concern here would be if it increases CA events. That is a possibility, but you won't know unless you try.

You can either continue using fixed mode or use autoset mode. In fixed mode, increase minimum pressure to 7.0 and in settings, turn EPR on, Full time at a setting of 1. This will give you a gradual introduction to EPR. We will move slowly to increase EPR if it does not increase CA. You can also try Autoset mode with a minimum pressure of 6.0 and maximum pressure of 8.6 with EPR On Full time at 1 to start.


RE: Flow Rate [mine too shallow?] - ShaunBlake - 07-15-2018

Sleeprider, you don't discuss Tidal Volume vs Flow Rate, just make suggestions for trying to improve TV.  Is it important to speak to the importance/lack of importance of Flow Rate?  And isn't it important to increase awareness of ideal Tidal Volume?

My understanding is that Flow Rate is an interesting number, and Tidal Volume is an indicator of a serious condition when below a range associated with one's BMI.  Is that an incorrect or oversimplified idea?


RE: Flow Rate [mine too shallow?] - trance - 07-24-2018

(07-15-2018, 09:38 AM)Sleeprider Wrote: If you want to increase your tidal volume a bit, and reduce the flow limitation (flat tops on inspiration curve) then using EPR might help.  This lowers pressure during exhale.  The difference in pressure between inhale and exhale can make breathing more comfortable, and the pressure-assist can help improve volume and reduce flow limitations. The only concern here would be if it increases CA events. That is a possibility, but you won't know unless you try.  

You can either continue using fixed mode or use autoset mode.  In fixed mode, increase minimum pressure to 7.0 and in settings, turn EPR on, Full time at a setting of 1.  This will give you a gradual introduction to EPR.  We will move slowly to increase EPR if it does not increase CA.  You can also try Autoset mode with a minimum pressure of 6.0 and maximum pressure of 8.6 with EPR On Full time at 1 to start.
Sleeprider,  I moved to pressure of 7.0 with EPR setting of 1 and recorded  8 days of data.  [attachment=7523][attachment=7524][attachment=7522]


RE: Flow Rate [mine too shallow?] - Sleeprider - 07-24-2018

I would just move the EPR to 3 and see if that makes any difference. Your summary statistics suggest one of your best results was when EPR was 3 for 43 days in February. In fact Autoset mode looks good. Keep the minimum pressure at 7 and maximum at 12.


RE: Flow Rate [mine too shallow?] - trance - 07-24-2018

[attachment=7528][attachment=7527]
I also have a question for anyone using a Contec Oximeter: Do your minimum SPO2 numbers show up accurately on your Oximetry Report? Mine do not, as the report always has them ridiculously low and this does not correspond to the strip chart. 


RE: Flow Rate [mine too shallow?] - trance - 07-24-2018

(07-24-2018, 01:23 PM)Sleeprider Wrote: I would just move the EPR to 3 and see if that makes any difference. Your summary statistics suggest one of your best results was when EPR was 3 for 43 days in February.  In fact Autoset mode looks good.  Keep the minimum pressure at 7 and maximum at 12.
Thank you. (I jokingly implied on an earlier thread that SleepyHead increased my AHI.)


RE: Flow Rate [mine too shallow?] - trance - 07-25-2018

(07-24-2018, 02:05 PM)trance Wrote:
(07-24-2018, 01:23 PM)Sleeprider Wrote: I would just move the EPR to 3 and see if that makes any difference. Your summary statistics suggest one of your best results was when EPR was 3 for 43 days in February.  In fact Autoset mode looks good.  Keep the minimum pressure at 7 and maximum at 12.
Thank you. (I jokingly implied on an earlier thread that SleepyHead increased my AHI.)
Last night, with Autoset 7 to 12, EPR 3:
[attachment=7540]