Between 2003 and 2018, I wore only a Medtronic pump. There were lots of Medtronic pumps that spent some time hooked up to my diabetic body, but the last one I used was the Medtronic 670G with the Guardian Link Sensor (a CGM). I wore this pump for nearly two years and wore the CGM for only half of that time. I had a lot of difficulty with this system, which ultimately lead me to taking my first every "Pumpcation" in 2018, to spend some time on MDI (Multiple Daily Injections). Read about my thoughts on MDI versus Insulin Pump here.
I spent a year on MDI and then after noticing some stubborn patterns in my Blood Glucose (BG) levels, my care team at Steady Health and I decided a pump might be the best thing for me. But I was not going back to Medtronic so instead hooked myself up to the Tandem T:slim X2. Read more about that transition here.
Below I'll be talking about the differences I have found between the two systems. I want to emphasize that this disease is unique to everyone. The way my diabetic-self handles eating a chocolate chip cookie is different, the way I live my life is different and because of the idiosyncrasy of this disease, the way I find best for managing my Type 1 Diabetes will be different too. I encourage you to critically think about what might be best for you based off what I talk about below.
Disclaimer: I am not a medical professional. Please consult your doctor before deciding to switch between the two options, as they can better guide you based off your diabetes management.
Exercise Mode v. Temporary Basal
I really liked the temporary basal option on the Medtronic pump. If I knew what kind of workout I was about to participate in, I could tell my pump what percentage of my basal to give me and this would keep my BG pretty steady throughout the duration of the exercise. It was all a guessing game though and took lots of trial and error. Tandem DOES have a temporary basal option but requires turning off Control IQ, something I haven't experimented with yet.
Tandems response to exercise requires pressing START on Exercise about 3o minutes before exercising so the pump can start to bring your BG levels around 160 and will then work to keep them there for the workout (since working out generally lowers BG levels).
Control IQ v. Auto Mode
Control IQ has been life-changing for me. What Control IQ does is estimate your BG levels about 30 minutes in advance and will decrease or increase your basal rates depending on the prediction.
Auto-mode on the Medtronic had a similar intention to adjust the basal rates every 5 minutes. This really comes down to the communication between pump and CGM though. We'll get to the CGMs next.
Dexcom v. Guardian
Dexcom was also a life-changing moment in my diabetes career. The Dexcom is painless, lasts 10 days and is SO accurate without requiring finger pricks. Because of the quality and reliability of this CGM, I think the Control IQ is able to do it's job at it's best ability.
I really wanted to like the Guardian link sensor. I had used one of the first versions of this sensor back in 2005 and it was like a whale harpoon. Painful and bloody. So when I saw this newer version in 2017, I thought wow at least it's not a whale harpoon. But the sensor still causes a lot of problems. I found it to be inaccurate and required a lot of calibrating. Here's where the problem was: whenever my BG would go down too fast or too low, or up too fast and too high the CGM would freak out and just stop working. I would have to keep calibrating and was at the beck and call of countless alarms.
Rechargeable v. Batteries
Maybe it's the new me trying to be more eco-friendly, but I love that the Tandem is rechargeable. I had a lot of worries about this because my phone is always on it's last bit of juice and is in need of constant charging but the Tandem and I have had no problems. The charge lasts about 5 days, and can be charged from 0% to 100% within 30 minutes. I disconnect it when I take a shower anyways, so I pop it on the charger and bam! All good. The charger is also a very common one that I use to charge my kindle and bluetooth speaker.
Medtronic requires AA batteries. I had a lot of problems with this because the charge would appear to be nearly full and then would drastically drop to empty and I'd find myself scrambling to find a AA battery. I remember staying at a friends cabin and sharing a room when my pump battery went to 0 and the alarm woke up the entire cabin. I had to scramble around a foreign cabin to find a battery and a quarter to unlock the battery capsule.
I hope this helps you decide which pump might better fit your lifestyle! Both pumps are life changing and are nowhere near the technology we had years ago. I am so thankful to both of them for making my life as a Type 1 Diabetic easier throughout the years. They are meant to improve our lifestyle as diabetics and definitely do their job to keep us alive and at our healthiest.