|The insulin pump not as smart as I had thought?|
August 27, 2009, 12:49:23 am
I've been using the pump for a while now. Long enough to know that it's not quite right yet... so I'm looking in to getting continuous blood glucose monitoring. This involves another sensor you put on your tummy, inserted under the skin for 3 days just like the insulins insertion site, but away from it to avoid contamination of the results.
Because it's not in the blood stream, the results are lagged by about 15-20 minutes. This is useful for determining faults with the basal and bolus rates.
This evening, two hours after my meal, I had given myself a dose for 80g of carbs.. but I was down to 80mg/dl bgl. The pump told me I had 5 units of insulin active. I suggested I wanted a bolus of 0g carbs to see what it would offer as a correction. Instead of subtract all 5 units of active insulin, it offered -0.5.
This concerns me a lot. I was under the impression that it would be smart enough to realize my correction ratio would mean the active 5 units of insulin would lower my bgl well below the safety threshold and give me a hypo. It did not seem to realize this - so I've taken some sugar and checked how many units it would normally give me for the sugar, then i subtracted the 5 units from that and ultimately gave myself 3.5 units of insulin directly instead of through the bolus wizard.
I wake up at 5am to get ready for my trip to ESUG in France, so I'll see then whether I got it right or not. If I got it wrong, then I've misunderstood something important about how the pump works. If I got it right, then I've uncovered a startling truth about the pumps behavior. I've also potentially confirmed just how wrong my current basal and bolus rates are. My suspicions will have further proof and I'll be even more desperate to get the CBGL sensors.
This is a terrible time to be making this kind of discovery, since i'm about to go on an intercontinental trip and be away from my doctor for a week and a half. But hey, that's life as a diabetic.. you either close up like a shell or you try and pretend nothing is wrong and attempt to live life normally.
I'll post again to let you know how the trip goes and what the reading is at 5am.