Slow, progressive Enlite ISIG degradation as the days pass

Continuing the discussion from Dexcom G4 sensors are driving me crazy! Help!:

While I am not sure I am really going anywhere with this post, I do know that I wanted to break it away from the previous (linked) thread about adhesive skin problems, a discussion which was largely Dexcom CGM focused. For those two reasons it had nothing to do with what I am talking about here.

As I said in the linked post, these days I’m glad when an Enlite lasts me until to day six since by that time the sensor is usually clearly fading away. The sensor sensitivity seems to degrade somewhat steadily over time for me.

I originally thought that this happened because my sensor probes would get “kinked up” the longer I wore them. But when I pulled this last sensor, its probe looked OK to me. Could this be a problem with the probe’s chemistry? Did I just get a batch of Enlites, lot B145U, which are all “less special”.

Since I just finished the WARM-UP for a new sensor, here is a comparison.

The first calibration of this new Enlite paired a Meter BG 100 with a sensor ISIG of 29.64. The first Cal Factor the pump calculated for the new sensor was 3.613.

On the AM of its sixth day the previous Enlite reported an ISIG of ~17 when my Meter BG was 110 lined. The Cal Factor the pump calculated at that time was 6.579.

About 7 hours later, a Meter BG of 186 seemed to line up with an ISIG of ~28. (The ISIGs were actually bouncing around so it was hard to tell). The last Cal Factor my pump calculated for that previous Enlite using the 186 BG was 8.222.

So … slowly but steadily my Enlite sensitivity seems to deteriorate. Not sure what my point is at the moment other than: Huh? Wonder what’s up with this? :confounded:

I’ve NO idea if its true (and I seriously think it is not), but one MM tech claimed that high bg’s “wear out” the chemicals on the sensor, reducing its life. I don’t get high enough often enough to prove/disprove that theory and when I told my MM trainer, she rolled her eyes in disbelief.

Some of my Enlites can’t get out of the single digits despite normal ISIGS for a day or more. I get really frustrated when I have a “weak” sensor and want to give up the whole idea of CGM, but then when I have sensors that go 12 days with super accurate numbers, I’m glad I keep sticking with the system. I would be thrilled if there was more consistency from one sensor insertion to the next. Maybe the next version will be better.