A day of much data & few conclusions
Ten hours came. Ten hours went. And still the Navigator only showed me the hour glass. No clue as to when it might calibrate. Or why it wasn’t.
Eleven hours came. Eleven hours went. Maybe my blood sugar is changing too rapidly. I’m still recovering from a correction for a nocturnal excursion triggered by Pizza Hut meat lover’s pan pizza and the new Premium M&Ms. Navigator is like an over-protective parent. It won’t let you calibrate unless conditions are perfect. Great. Just what we need. A CGM that only works when your blood sugar is perfect.
Guardian will let you calibrate at any time. Of course, if you choose a bad time your accuracy goes to hell. Still, at least this allows the flow of some information. Trend, direction, and speed. It is better than flying blind.
But I am late to work, so I fly out the door. Driving across the mesas, the rising sun at our backs, my belt vibrates. But who is talking? Guardian, Navigator, or Cozmo? I got a lot of gear on today. It is Guardian, with a fall rate. The correction boli is cleansing me of my dietary sins of the night before. Penance and forgiveness for the pizza orgy.
Now a different vibration, more baritone. Ah ha! Navigator speaks. It is asking for blood. We pull to the side of the interstate and I dig around in my cargo pockets for my vial of precious FreeStyle strips. My commuting buddy looks on with a mix of professional and personal interest. My life-support gear is the source of endless fascination for my co-workers.
I find the vial and fish out a strip. I slide navigator out of her home on my belt, and rotate her around in my hands looking for the corner that has the strip port. I find it and insert the b&w strip. They always remind me of the old “cow” boxes Gateway computers used to come in. The Navigator’s screen lights up and gives me a chance to dial in the right strip code number. Navigator uses “old style” test strips, not the newer FreeStyle Lite self-coders. It takes a long time to get through FDA.
Ready for blood, I’m now grateful for the dual-side-loading design of the FreeStyle strip. Easy to maneuver the device to the blood drop on my finger from pretty much any angle. Slurp!
Then a clock graphic appears. I am informed that the Navigator is “processing.” It seems to take a long time. 210. The Navigator asks me if this is a Control Solution. I tell it no.
Then nothing happens.
“Did it work?” asks Eve.
I don’t know.
Navigator didn’t say anything. It isn’t showing anything. Very mysterious. I check the CM status screen under “reports” and the various checklists say “OK,” but there are no details. Not much help.
I return to the main screen and there it is. Glucose CM 210. We are live!
So right off the bat, there is one thing I don’t like about Navigator. Ya’ gotta press a button to find out what your sensor glucose is. Now long-time readers who have been with me since the beginning might remember my delight with Garage-door Guardian at being able to press a button to see what my blood sugar is. But now I am soooooooo spoiled.
Modern Guardian can stay on all the time. I can glance at it and see my glucose; like glancing at a watch. Would you want a watch that made you press a button to check the time? Oh, wait. They used to make those back in about 1979. They were called LED watches. Funny. You don’t see them anymore. Probably because no one wants to have to press a button to do something that for years you could do by glancing at your wrist without pressing a button.
Of course being on all the time eats up your batteries more quickly. But that is a choice I’m happy to make. Guardian can be set to stay on or shut off. I wish Navigator had done the same.
Oh, I need to update you on the Navigator’s fat belt clip. It turns out it is a flip-clip. You can flip it perpendicular to your body to view sensor glucose…..I kinda like it….
Click-click-click-click-press. (Navigator) 166 with 45 degree down arrow.
Click-thunk. (Guardian) 214 with one arrow up.
Well….that can’t be any more different, now can it?
Snap-slurp-beep. Presto says 189. Of course a meter can’t give me trend, can it? We’ll have to wait and see who’s right.
What?! Who’s buzzing? Oh, must be Guardian, I’ve got Navigator set to squawk most of the time to see if her voice is louder (I only set Navigator system alarms, such as time to calibrate, for vibe).
Now, just a few minutes after the no-one-is-on-the-same-page checks, Guardian is alarming a fall rate. So the two CGMs agree the blood sugar is dropping. Or do they? Now Navigator shows 154 but no arrow. So…..where the fuck is the TRU arrow? Is it not being True to Me? Guardian only uses arrows when you are changing rapidly. But I thought the TRU arrow was the Navigator’s compass rose: it is always supposed to point some direction.
“The skipper he stood beside the helm,
His pipe in his mouth,
And he watched how the veering flaw did blow,
The smoke now West, now South.”
--Wreck of the Hesperus, Henry Wadsworth Longfellow
Guardian predicts a low. She’s at 138 with dual arrows down. Navigator shows 148 with a 45 degree angle down. The horses are at the starting gate. The race is about to begin. Presto shows 164. Hmmmmmm….too much technology can definitely drive a man crazy.
Guardian is bouncing around a lot today, which is the second day of the sensor in question. It should be running stable and clean. Yesterday, it preformed like a champ, but I was having a pretty good day with stable BGLs. We’re on a wilder ride today and Navigator only has the benefit of one finger stick while Guardian has had several. The first round goes to Navigator. I’m impressed.
I decide to access the Navigator’s graphs. Right click. Down twice. Line graphs. Select two hour. And I get a sweet little graph showing a steady drop from the starting point of 210 down to the current 145. I have the choice of 2, 4, 6, 12, and 24 hour graphs. The screen stays live long enough for me to study, but when it winks out, I’m back to the main screen again and I find myself wishing that Abbott had seen fit to let me choose my time-out time. As I’ve only been “live” a short time, the two hour graph is the only sensible one to look at. Guardian’s graphs display on a rectangular screen, Navigator on a square. Unless the rate of change is radical, I’ve always found Guardian’s 3 hour to be worthless. It is so stretched-out that it looks flat most of the time. I like the Guardian 6 hour screen a great deal. Twelve is OK too, but the 24-hour is worthless as the screen is too small for the amount of information in it. It will be interesting to see how Navigator’s screens compare.
It is now 9 a.m. Guardian shows me at 96 and still dropping like a stone. Navigator shows 136 with minimal change. Presto, always the tie breaker shows 146. (It is worth pointing out that Presto is a hematocrit compensating meter, so while closer to a lab reading, is commonly slightly higher than a conventional test strip like FreeStyle. Navigator is calibrated with the FreeStyle. That said, Guardian is calibrated with the Presto so she shouldn’t be so damn far off. Right now, Navigator is performing much better in a state of rapid change. But this is only the first hour of the shootout. Too soon to jump to conclusions (or jump ship).
9:30 a.m. Guardian, predicting a low 15 minutes ago, now gives a rise rate alarm, followed by a high. She’s showing 174 with two arrows up. Navigator shows steady at 120. Presto shows 130. Guardian seems to be having a nervous breakdown today. Is she jealous that I’m courting a new CGM? Women!
Or….I’m wearing two wireless devices. Could one be somehow interfering with the other? So I don’t know what the fuck is up with Guardian today, but Navigator is showing a very nice Cozmo-driven correction bolus from this morning.
9:45 a.m. My belt buzzes. Bzzzzzzzzzzzzzzzzt. Long and steady. Guardian is more like a wood pecker. Bzzzt. Bzzzt. Bzzzt.
Yo hablo Medtronic. Yo hablo Abbott. I am learning.
Navigator wants a BG test for her second calibration. Has it been two hours? I guess so. Out comes the white vial. BG on built-in FreeStyle meter is 121. Navigator shows 115 with flat arrow. Presto calls the game at 133. Guardian, still freaking out, shows 182 with one arrow up. Now I’m set on Navigator calibrations for 12-20 hours. I’m past the worst part, timing wise. I have a wide field to choose my third cal of 4 needed over the five day run of the sensor.
10:21 a.m. Navigator 98 and stable. Guardian 164 and stable. Presto 116. Fresh cal given Guardian.
Bzzzt. Bzzzt. Bzzzt. 10:45 am. Guardian speaks up with fall rate and low predicted. She’s got 104 with two down arrows. Navigator has been silent so far today. I rotate the clip upwards (I’m really beginning to like this feature) and wake her up. I’m showing 85 and level. Presto has 103. Hmmmmmmm….
11 a.m. sharp. Bzzzt. Bzzzt. Bzzzt. Guardian calls a low at 74 with two arrows down. Navigator is steady at 83. Presto calls the game at 88. My fingers are really taking a bruising today. The sensor ISIG on Guardian is really low.
Navigator 76 level. (coasting very low, but as of yet, no predictive alarm).
Guardian 112 one arrow up.
Navigator. Teee! Teee! Teee! Three brief sharp Soprano tones. High pitched, but with authority ! Low Glucose. 74 level.
Guardian 118 stable.
Took sugar, 15 carbs.
Navigator 71 level. Low alarm repeats.
Guardian 114 level.
Then hospice came. Well, not for me personally (thank God). They brought pizza for an in-service.
Bzzzt. Bzzzt. Bzzzt. Guardian High predicted with two arrows up.
Navigator 127, 45 degree up arrow.
Navigator seems slow to catch a rise.
Guardian 190 High Alarm two arrows up.
Navigator 137, 45 degree arrow up.
Guardian 198 two arrows up.
Navigator 140 level.
Guardian 244 level.
Navigator 186 level.
None of these fucking CGMs work right….
Fall rate alarm. Guardian 202 two down arrows.
Navigator 193 level.
Teee! Teee! Teee!
! High Glucose. WTF? Why didn’t I get a projected high alarm first? I double check to make sure the projected alarms are turned on. They are. Hmmmmmmmm….same tone for high as low. Bummer. I had hoped she’d have a separate voice for each occasion.
Guardian 266 one up arrow.
Cozmo advises 5.15 unit Novolog correction.
When I next look, I’ve lost telemetry. Crap. I’m told I need to reconnect. Not a scary as it sounds. I don’t need to pull the transmitter out or anything. Main>System>Reconnect>Select.
Wait 70 seconds. Beep-Beep. Up and running again. Guardian will automatically hook back up following a signal loss. Guardian also stores a half an hour or so of data in the transmitter for upload to the receiver if telemetry is lost. Navigator does not.
As the day winds down I’m disgusted with CGMs, blood glucose meters, and diabetes in general. I down load the devices and without looking at the images, send them all home to view over a glass of wine.
Next time: here’s looking at you.