670G Week One: Manual Mode

In my last blog post I told you that I decided to try the Medtronic 670g. Even though being on an insulin pump hadn’t improved my glycemic control in the previous 9 months, I still held out hope for this new pump. My insulin needs didn’t follow a pattern that either I or my doctors could get a handle on, and I was curious whether having the ‘hybrid closed loop system’ take over and make its own decisions minute by minute would do the trick.

I agreed to pay the $299 fee directly to Medtronic, which would be refunded to me if I returned the old pump, did a few surveys, and wrote a testimonial. This fee was outside any cost that my insurance was paying. It seemed a bit like blackmail—what if I didn’t like the pump? Could I give an honest testimonial and still get my money back? I laughed off my skepticism, even though it still sat a little funny with me.

My doctor’s office is over an hour away, so we decided that with my experience using the 630g system, I could skip coming in for the first ‘hook up’. I could set up the pump myself and use it in Manual Mode for the first week. Then I’d come into the office for a crash course in Auto Mode, and put my life—or at least my basal insulin rate--into the hands of Artificial Intelligence.

When the boxes arrived, I waited to open them. I would need a few hours of uninterrupted time and a whole lot of space in my tiny abode to set this thing up. I was also working myself up to being “tethered” again. I wondered if Millennials have an easier time with this. If they’re accustomed to carrying smartphones everywhere and having headphone cords dangling all the time, is it in any way similar?

A few days later when I had a free morning, I unboxed the whole shebang.

The 670g looks identical in size and shape to the 630g. The Guardian sensor also looks pretty much like the old Enlite sensor, although I’d been assured it was much more accurate. It had to be, I thought, or the FDA wouldn’t have approved it to be ‘in charge’ of my basal insulin delivery.

As I laid out all of the pieces and parts, the old ball and chain feeling came back, but I told myself I’d give it six months, and if it didn’t help, I would go back on MDI. I also told myself the real ball and chain would be going blind, wheeling around in a wheelchair with one foot, or having dialysis several times a week.

As I filled a reservoir with insulin, a new feeling of dread hit me. Time to insert an infusion set. My troubles with Quicksets had spooked me, leading me to stop using the 630g. But in the meantime I’d been advised to try Sure-T infusion sets. At first I was scared of its steel needle, but have since found these to be the most reliable and comfortable infusion sets for me. One obstacle down.

Next, I got all of the wireless devices connected to each other—pump, CGM, and glucometer. Then I programmed in the basal and bolus settings from my old pump. But this one had a new feature. On the advice of my CDE, I turned on the Smart Guard feature, with ‘Suspend Before Low’ and ‘Suspend On Low’ activated. Most of the other alerts I left off. Otherwise there’d be too many alarms and they’d drive me nuts, she said.

The minimum time in Manual Mode before starting Auto Mode is 48 hours, but I did a week. During that time it’s learning about you--exactly how and what, I don’t know, and I’m sure it’s proprietary information. It’s probably also a test run of the system components, assuring they’re all functioning together.

I loved this first week. I tend to go low from exercise or activity, especially my weekly cleaning job. Smart Guard was able to predict that, cutting off my basal before I went hypo. Other times I went low, but it wasn’t a crashing low. I could tell from the graph on the CGM that I was gently dipping below 70, and would come back up on its own in 10 or 15 minutes.

It struck me that as Type 1 diabetics, we’re operating in our own version of Manual Mode. We do manually what other people’s bodies do automatically. A portion of our brainpower is constantly, eternally, dedicated to those calculations and variables that affect our blood sugar. If Auto Mode could take away even some of that burden, what a relief that would be. I was eager to go to my appointment, get started in Auto Mode, and begin my hybrid life.