Last Thursday, I went in to get set up for a five-day run with a continuous glucose monitor (CGM).
Quick overview – with type one diabetes, the pancreas up and quits producing insulin, because it’s a LAZY SLACKER! Therefore, I take insulin via an insulin pump, which delivers a baseline dose throughout the day, and allows me to program additional insulin when I eat. I check my blood sugar about six times a day to help me keep it within a relatively healthy range.
The CGM is a device that automatically checks your blood sugar every five minutes. It automatically sounds an alert if your sugar goes too high or too low. (Sadly, it can’t be programmed to do the red alert klaxon from Star Trek, but some day…)
It works by measuring the interstitial fluid, as opposed to the blood, so the measurements aren’t quite as precise as the ones from my glucose meter. But it does a great job of showing trends (whether your blood sugar is climbing or falling or just chilling and hanging out). It also produces a graph to let you see what your blood sugar is doing over time.
I was hooked up with a Dexcom CGM, which involves a tiny flexible needle that goes into the side of the belly and is hooked up to what may or may not be a T-800 chip from Cyberdyne Systems. This made me a little nervous, since I’ve already got the catheter from my insulin pump stuck to one side of my belly, and the CGM is a little bulkier, as you can see here.
This was at the end of my five-day run, and you can see that the adhesive around the edges was starting to give up.
Along with the Skynet Chip, there’s a handheld receiver that needs to be kept within about five feet. It records the readings every five minutes, and also lets you enter data like how much you’ve eaten or how much insulin you might have taken.
The whole thing takes two hours to boot up — they said it takes time to calibrate, but I think that chip might be running Windows ME — and then it basically runs on its own. It does ask you to input you glucose meter readings from time to time to make sure its readings are matched up to yours.
There are a few downsides (in addition to being one step closer to becoming a Cylon). The receiver buttons are annoyingly loud. Given how I tend to obsess over data, I spent too much time poring over the graphs, and probably overthought things a bit. The biggest challenge was because food and insulin don’t have an instant, real-time effect on blood sugar. So if my sugar was dropping, I’d grab a snack, but the readings would continue to drop for at least another 10-15 minutes … which meant I tended to overcompensate. Likewise with taking insulin when my sugar was too high.
Overall though, I liked it. I really like the safety of that alarm, which would help me avoid extreme highs and lows. I already picked up on one way I need to adjust my insulin boluses at meals. I’d be able to do a better job of fine tuning my insulin pump’s baseline dose.
Will I get one of my own? I don’t know yet. Like most of the toys keeping me alive, this one isn’t cheap. A friend said she was looking at paying about a hundred a month for hers, with insurance. And one of the things the doctor and insurance company will probably look at is whether or not I need a CGM. It might help me better control my diabetes, but if my diabetes is already under good enough control, is it worth it?
But I’ll sort through all of that later. For now, I’m just amazed at how far the technology has come. 30+ years ago, you’d pee on a strip, compare the color to a chart on the canister, and that would tell you very, very roughly what your blood sugar had been about four hours ago. Whereas I’ve spent five days walking around with one computer giving me my insulin while a second, wireless computer provides near-realtime information on my blood chemistry.
It’s not a bionic pancreas, but it’s still pretty cool.