My father and the numbers
I've been trying to understand things beyond my normal experience. Beyond my education. And, perhaps beyond my intelligence.
Sensor number eight has been acting up. Running high. Too high. I’m back to being THE NEVROUS DIABETIC.
My first two weeks were wonderful. Like a fairy tale. But with the 7th sensor crapping out and number 8 not acting like the first six, I find myself becoming paranoid. I don’t trust the girl as much as I used to....and she’s a lot of work and money. If I can’t trust her, what’s the point?
Medtronic has provided me with 16 pages of clinical study data in the back of the manual. I'm looking through all of this to try to answer one question: were my first two weeks typical performance and the recent trouble an anomaly, or the other way around? I'm struggling to understand what the information is saying. I wish I could call my father and have him explain it to me.
Although I remember once, when I was in college, I called and asked him a stat question. A deep sigh in the phone. A pause, and then, finally..."Well, you do have a copy of my book, don't you?" Yes, Dad. "Well I cover this quite toughly in chapter two." I was told to read chapter 2 and THEN call back if I still didn't get it.
I've looked though both of the books my father wrote tonight, but his voice isn't speaking to me through them. I'm on my own with no one to call if I don't get it.
Here is what I think the data tells us. I may not have "gotten it." So don't treat this like it is carved in stone.
The help line’s official number is that the Guardian readings are plus or minus 13.8% of a finger stick, but looking over the clinical studies it is not that simple. The results are non-linear. That means that in some ranges it is better than the 13.8 and in other ranges worse.
Medtronic have compiled various data into an analysis to show how readings could effect real world situations. Overall, about 62 percent of readings can be considered "clinically accurate." Around another 35 percent of readings would lead to "benign" decisions. In other words, yeah, off a little, but you wouldn't hurt your self. So the machine is considered golden about 97% of the time. That's damn good. But what about the other 3%? Well yes, this is the zone where you can kill yourself.
Part of that number includes lows that are not detected. The system is not perfect. Is it still worth it? My feeling is the money is well spent catching 97% of my trouble. Besides, this is not the only game in town. I'm still using my BG meter and my brain. Even though I can't feel lows I can recognize when my behavior has put me into a situation where they are more likely and I can exercise more vigilance. Might it miss a hypo? Sure, could happen. Might I miss one on my test strips? Yes, and once pre-Guardian I had a real close call. Might the Guardian catch something I would otherwise miss. Yes, 97% of the time.
Might I have a "perfect storm" with me out to lunch and the Guardian in 3% town? Could happen. And what would happen then? Well, hopefully my wife would remember how to use the Glucagon kit. (My pharmacist had a good friend who died of hypo. His frantic mother injected the saline with out first pushing it into the vial and then drawing it back it. These ain't Epi-pens. My advice: have your loved once "practice" with expired kits before you toss them every six months.)
There is a ton of data. Tables. Charts. Columns of figures. It is late at night. My mind is muddled and I am depressed by all that has transpired. But I’m feeling encouraged. Tomorrow I’ll sleep in. Then I’ll get up and look at the data again and make sure I’ve got it right. After that I’ll look over the download of my data again carefully and try to figure out what’s going on.
SIX HOURS LATER...........
This morning I was planning to sleep in. I was up late last night studying the clinical studies data in the back of the Guardian manual, trying to divine how well it is supposed to work. But I woke up at 8. Laid there trying to get back to sleep with no luck. May as well check the BG. Cozmo has me at 65. Kinda low. I take the Girl off of the nightstand and flip open the case. Click. 90.
$#%&^*@ #%#%&% $^*&%##!!!!!!
Or words to that effect. I retest with Cozmo. Now 64. I take a half a cherry slice and roll over and try to get back to sleep. No luck. I’m too pissed off.
I get up. It is site change day for the pump, but not until tomorrow for the Guardian. The sensor that died threw us off the system. A normal site changes seems so simple. So little to do.
I gather up my notes and call Medtronic. The poor guy at the 24 hour help line really gets an ear full. Among other things I dump on him I tell him this is too damn expensive not to work right and what are my return privileges if I want to throw in the towel?
He is exceeding polite to me, even though I’m probably near the edge of being nasty myself. These Medtronic folks are professional. He doesn’t know why I'm so far off, and he doesn't know about the return policy on the Guardian, but he’ll find out.
As promised, he calls back within the hour with THE PLAN. First off, the Guardian has a 30-day return. As we are closing in on 30 days they want me to know they are going to extend that for me. They want the machine to work for me and we are going to work together to try and make that happen. However, failing that, they’ll take her back and refund my money. Cool. I’d much rather spend the rest of my life like I’ve lived the first two weeks, but if that was just beginners luck then I’d rather have the money back in my checking account.
They ask me to email all data from hook up until today. They’ll analyze it and with in 24 hours they’ll call back. We’ll conference call with tech, help line, and me. We’ll all be looking at the same data on our computer screens and try to figure out what’s going on.
Tomorrow: Good News for Wil and the girl