My first ever attempt to notate an iPhone screen shot. Be patient with me. Prebolus was novolog. Took 4u afrezza correction at the point where I noted that the meter said 175. The cgm said 128 at this point and then bumped to 145 shortly after… way way behind real time
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Typical sensor life for us is 12 days.
Yesterday we had a very rapid rise post-breakfast where the BG delta point-to-point exceeded 20 for some time. It seemed a classic example of an unstable system. (I know the underlying cause of the rise but trying to stay focused… lol )
However the difference from what we had to what @Sam had is that we don’t have the Afrezza. So for Sam it ended up being a little blip. For us, it impacted the entire day. Huge high followed by yo-yo.
Sam - I think the graph looks great. Something in dinner was more than the pre-bolus accounted for or the timing was not perfect or whatever. The CGM picked it up, the fingerstick confirmed it (although not exact between meter and fingerstick) and the Afrezza corrected it. From our point of view the entire thing looks awesome.
Oh - and GREAT screenshot (with notations).
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Thanks-- though my objection is that the cgm seems to be painting s much rosier picture than the reality
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The sensor will change its reading when the electrical signal goes up in the system. Now if you are pushing a sensor by using it for a long time, it will have some enzyme die-off during operation, and so as time passes it will be harder to generate enough electrical signal to push the sensor reading up. If you are having the issues in the first week of operation, then I would just chalk it up to the vagaries of blood sugar propagating through interstitial fluid dynamics.
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This would be one of the reasons for the periodic calibrations - no?
Assuming so, how would the Libre “no calibration” system handle the issue?
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That is part of the reason to require calibrations, the other is to counter drift in the response of the Dexcom system. This is required because the response isn’t linear in these types of sensors.
In the Libre, the response through the operational life doesn’t change (part of why they don’t last a really long time). Also, in the Libre, the response is perfectly linear through the physiologic range which is why you don’t need calibrations.
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