Perfect Storm

So, Cat has been using the t:slim with Control IQ in the clinical trial for about a month. Here are my thoughts:

I do love the fact that it corrects a high blood sugar with 60% of our correction factor once per hour if we underestimate the carbs or don't pre-bolus early enough. That's a nice feature! However, sometimes I wonder if our correction factor is right...the pump uses the data that *I* put in, so if I put the wrong info in the pump, then she will not have a good correction for highs. Honestly it seems sometimes like it's driving her a little too low, so I'll continue to keep an eye on things. We might need to change the correction factor on our end. Also, we love the Dexcom G6 more than anything. It's SO wonderful not to have to calibrate and poke fingers to find out her blood sugar. Once we are finished with the trial, she will go back to her Medtronic 670g pump with 2-3 calibrations a day and at least 2 fingersticks per day. I really hope that Medtronic gets it together with their sensor for the next generation pump and makes it more like Dexcom. The Medtronic CGM that pairs with the 670g pump is awesomely accurate. It just sucks to have to calibrate it twice or more a day. Believe me, I know ALLLLL about it since I'm living it!

Here's just a little info..nothing to do with this particular pump or with the t:slim infusion sets: If your insulin pump infusion set needs to be changed (which is is supposed to be changed every 2-3 days), there is nothing you can do about higher blood sugars until you put in a new infusion site. (Side note: once you've had a foreign object inserted into your skin, in particular a metal needle that infuses insulin under your skin, your body naturally tries to reject it and it does what it is supposed to do to try and heal that wound. Sometimes the insulin is just not absorbing well under the skin due to the area being inflamed from having metal stuck into it.) This particular day was a one of those days for Cat. And of course it always seems to happen at the most inopportune times! Like when I promise her we will go to the frozen yogurt bar after school and get a MEDIUM cup of Fro-Yo with whatever toppings she wants!

We've been talking all week about going to our favorite used book store (The Recycled Reader) and a treat at Berri-licious Frozen Yogurt. We tried to go last Saturday, but Cat was throwing up and having diarrhea after her soccer game, so that kind of dampened our plans. Anyway, last Saturday, we were able to finally go! We both found some cool books that I wanted and we got a pic of her with her JDRF OneWalk shoes for the fundraiser that Jane and her husband Bud so graciously agreed to support!

Anyway, after her Fro-Yo (which I totally guessed the carb count because...what the heck? How can you carb count all that stuff?) and afterwards she started going up and up and up and up, but gradually, so it wasn't like off the charts crazy high.

 I gave her a correction but she still was going up. I changed her site and gave her more of a correction. She needed a site change anyway. This seemed to help.

When it was time for dinner, she was trending down, so I bolused her and hoped for the best. Now she's going down down down...it's like the insulin started working all of a sudden! Sooooo irritating. And the worst part is, the Dexcom lags behind actual blood sugars by about 15 minutes. I just checked her with a fingerstick when I got an alert on her Dexcom, and her actual blood sugar was 80. Not an emergency at all and that does not need to be treated. That lag time stresses me out!

Graph after Fro-Yo and mystery bolus

So, in the end, it wasn't a huge deal. We had a tall mountain peak of high blood sugars that came down relatively quickly and it all ended well. Still...seeing that giant spike always stresses me out. Fortunately it doesn't happen often!

Until next time....

A little over one week with Control IQ

A Week in Review: 

Dashboard Summary from the last week of our t:slim Control IQ trial. 

A full week + one day has passed since Cat started the t:slim pediatric trial. At first, I wasn't sure what to think about it. She had some highs and some lows over the first couple of days, to the point where I wasn't sure I'd made the right choice, having her participate in the trial.

And then school started the Monday after she started wearing the pump. I shared her graphs and how much time she was spending with her insulin suspended (because of the increased activity at school) in my last post.

But after a full week in, and I think we are settling into a new normal. The pump seems to be figuring it out. I honestly can say that this pump/CGM combo has us thinking less about diabetes than we ever have. When things are going well (no pump site failure, like earlier this week), I don't even worry about her numbers. She's had some highs overnight the last couple of nights.  Not sure why (growth hormones? Fat/Protein rise from dinner or dessert?). But I haven't had to get out of bed to correct her because the t:slim does that for me. By morning she's in range and ready to go. In fact, I haven't corrected her at all or even touched her pump except to bolus or to suspend delivery for swimming, etc.

The fact that the Dexcom G6 has NO CALIBRATIONS and NO FINGERSTICKS is more amazing and liberating than I ever thought it would be. Like, a huge stone has been lifted off of my chest. There have been so many times that I have stressed out about when to calibrate on the 670g because blood sugars need to be stable, so that means you don't calibrate after you eat. But if you forget to calibrate and then you eat....then whoops! You might be without CGM data for a few hours till your blood sugar stabilizes. With the Dexcom G6, you just don't have to worry about that at all. I know Cat's dad loves this feature because he was ALWAYS forgetting to calibrate when I was out of town, leading to increased anxiety about loss of CGM data.

Now what I don't love is the Dexcom Follow app. Yes, I know that sounds crazy. But when we were on the 670g, we used Nightscout and it was AMAZING. I could see all sorts of information from her pump besides her blood sugar graph. More about Nightscout later on, but for now, I'll share some of her graphs from T:connect. Oh, and yes, I love T:connect SO MUCH MORE than Medtronic Carelink. SO MUCH MORE. <3

Trying to be a Pancreas

(I wasn't planning on writing another post so soon after the one I wrote last night, but I felt the need to get this out there and this seemed like the easiest way to do it!)

Day 2 without our Guardian 3 sensor and Auto Mode: 

UGH. I didn't realize how amazing Auto Mode on the Medtronic 670g was keeping Cat's blood sugars. She typically has a flat line overnight and stays around 120. I know that within the Diabetes Online Community (DOC), that is a bigggggggg debate/source of contention...the fact that the 670g has a target of 120 and some people think this is too high and would rather set a target of 80 or 90 and blah blah blah, but I'm OK with us sitting at 120 all night, if we are steady and stable. Call me lazy, call me busy, call me both lazy and busy, but I really don't have time to be a pancreas x 2 ALL OF THE DAMN TIME. I have a full time job outside of the home. I have two other children. I have a dog and two cats. Plus I like to do stuff other than diabetes. Like scroll Facebook. And binge Netflix. So, the Medtronic 670g hybrid closed-loop system has really helped us not have to focus on diabetes as much, and it's been great. 

But yesterday and last night, she was using her regular basal rates and insulin sensitivity factor (ISF) along with the Dexcom. The basal rates are ones that I preset in her pump for use in Manual Mode. And clearly they needed adjusting. 

See that dip between 3 AM and 6AM? That's where I stumbled in and corrected her high blood sugar in the middle of the night. See how it went down, stayed kind of steady for a while, and then went back up? I think that both her ISF was not right nor were her basal rates. I did a major correction this morning and changed both her basal rates and her ISF. She's coming down slowly....I'll have to keep evaluating and adjusting throughout this week.

Please please please let us get in the experimental part of the clinical trial with Control IQ. I am not sure I can handle 4 months of having to be an active pancreas.

Dexcom Vs. Medtronic Guardian Sensor - An Anecdotal Report

For the past week, Cat has been wearing both the Dexcom Continuous Glucose Monitor IN ADDITION TO her Medtronic Guardian 3 sensor that communicates with the Minimed 670g insulin pump.

Since she's doing the "run-in" phase of the pediatric clinical trial for the Tandem t:slim Control-IQ system, I decided to have her wear both and see how they compared. Fortunately, Cat is a good sport and didn't mind wearing two sensors to satisfy her mom's curiosity. 

First, let me backtrack and say that we have had basically no issues with the Medtronic 670g pump. Cat has been wearing hers since January 2018 and I have been wearing mine since January 2019. I am completely happy with the system. We have amazing time-in-range and few incidences of hypoglycemia, which are the new indicators for diabetes control as opposed to the older standard of A1C.

However, I'm not brand-loyal when it comes to insulin pumps and CGMS. Sorry not sorry! I'm always looking for the newest gadget and the latest and greatest in diabetes tech gear. So trialing the Control IQ sounded like a really cool idea! (For what it's worth, I requested to be in the next generation Medtronic 780 pump trials, but the closest trial location was too far for me to drive on a monthly basis). I've used the Omnipod, the first generation Tandem t:slim and now the Medtronic 670g, so I have good experience with insulin pumps. But I will jump on the first ship that sails when it comes to the best technology for managing Type 1 Diabetes!

So ANYWAY, like I said, Cat has been wearing both sensors for the last week. And in my opinion.....

MEDTRONIC GUARDIAN sensors were hands down the most accurate. I'm sure some people will disagree. However, how many naysayers have worn both sensors simultaneously? And I do have data to back this up!

Part of the trial requires that we use their Accu-chek meter to test Cat's BG. So sometimes I used the same drop of blood and checked her BG with both the Contour NextLink 2.4 meter (that is linked to her pump) and the Accu-chek, the clinical trial meter. BOTH meters were always within 5 points of each other when I tested with the SAME drop of blood, so I'd say they were both very accurate. However, when I compared the two meters with the Medtronic Guardian sensor and the Dexcom sensor, the Dexcom sometimes read 20-30 points higher than the two meters AND the Guardian sensor.

I will say there were times that the two sensors were spot on, especially early on. But it seemed like the later in the week that we got, the more the Dex was reading a little higher than everything else. But...who's to say that they Dexcom isn't right and the other three devices were wrong? I mean, there is a margin for error with meters as well. So there's that. I definitely didn't worry that the Dex was reading a little higher at times...it was not so off that I felt the need to calibrate it. And I would rather it trend higher rather than lower, too.

I'll provide some pics of the device comparisons below. Some are close and some are not so close. 

This one was on the first day of the Medtronic sensor. VERY close. I was extremely excited. 

These were a little off, but still within range of each other. NBD. 

Here they were all different, but still within 30% of each other so it was fine. 

This one was a little concerning...that's quite a difference! See how both meters basically matched the 670g but the Dex was 20-30 points higher? We saw this MULTIPLE times over the course of the week. Still within normal, but it was weird how Dex ran high more often than not.  

As far as which we liked the best, I'd say hands-down Cat prefers the Dexcom. The insertion is simple, the taping is simple, the no-finger pricks, no calibrations....MAJOR pluses. Also, the Dexcom G6 has a 10 day wear, opposed to a 7 day wear with the Medtronic sensor. (I've seen many complaints in the Diabetes Online Community about the G6 not lasting the full 10 days, and maybe it won't, but we are at the end of day 8 with no issues so far so I'll call that a win). 

I will have to say I love those features too. But this is week 2 with the Dexcom + Medtronic 670 and I am going to let her wear JUST the Dexcom. And the Dex doesn't talk to her pump. And that means we will lose the "suspend before low" feature in Manual Mode as well as the Auto Mode program which adjusts her basal. We've had really good success with Auto Mode keeping her in range, and I'm going to hate to have to micromanage her pump in order to do the same job. It will be hard! But, I'll deal with it for the sake of science and research for Type 1 diabetes!

And so for this week (week 2), we are NOT wearing a Guardian Sensor with the 670g pump,  and we are using the Dex for boluses without fingersticks or calibrations. Unless we need to fingerstick for whatever reason (her symptoms don't match the number on the Dex, or it's a first day sensor), then the Dexcom will be our guide. 

Next week (Friday) we will find out if we are in the control group for the t:slim (where we will wear the Dex and her medtronic 670 with no Guardian sensor, like we are doing this week), OR in the experimental group (wearing Dex + t:slim with Control IQ). 

I think it's obvious which one we are hoping for....stay tuned!