Does anyone else set a higher-than-needed basal rate on their Tandem pump since Control IQ will keep you from going too low?
I don’t think the Tandem x2 pays attention to the basal rate unless CIQ is turned off or your CGM sensor is off. So it is really irrelevant what the basal rate is set to. What the Tandem pays most attention to is the Correction Factor.
Control IQ will regulate basal insulin depending on CGM data. When C-IQ is turned off or the pump loses connection with the CGM. Then the pump uses the set basal rate set in the pump.
This has nothing to do with correction factor. That’s along with g:u are set in the pump. When doing a correction or meal bolus, the pump will come up with units. The important thing is you can override that suggested dose.
I’m currently on prednisone which makes being able to override great. My endo suggested I change settings but I convinced him I’m better at extrapolating than the pump, and when I am through with this awful but necessary drug my pump settings will work well.
Here’s a screenshot shot of C-IQ doing its stuff during sleep mode and before prednisone. Notice the meal prebolus I did for breakfast.
You can raise basal a bit over your normal rate. The downside is if your pump loses CGM data it will go to your basal rate set in your pump. This could lead to overnight hypoglycemia.
1 Like
You said it better than I did. Yes, overriding pump suggested bolus units is what I have been doing since my first Tandem, almost 8 years ago. I do that because I feel best between 80 and 100, while the pump is preset for a target of 110 in Sleep Mode. I have been using Sleep Mode 24/7. And my pump wants to keep me at 124 all night long. When I consulted the Tandem CDE about this, she told me to slowly reduce the Correction Factor until I get the pump to the numbers I want. Reducing the CF number makes it stronger. I am still working on that because I am fearful of going really low. But it seems to be working… slowly. That, and using Sleep Mode around the clock are the only changes that can bring the range down. I was told the same by the Tandem Area Manager.
My trainer calls 25/7 sleep mode users sleep walkers. Another thing to do to get BG below 110mg/dl is to increase your weight on the pump. This is not something Tandem would suggest.
I don’t know where I learned about this, maybe here.
1 Like
You are absolutely correct. I should have included more information about using a “higher-than-needed basal rate” in Control-IQ. I only use this inflated rate during waking hours for the reasons you stated.
I also keep my Control-IQ set to sleep mode. While in sleep mode, IQ automatically adjusts the Basal rate to reach the target as shown in the following table. (IQ in sleep mode never makes a correction Bolus, but one can be done manually.)
1 Like
I think that understates how often the basal rate the user sets is used. It’s the default and, in my experience, Control-IQ leaves it there a lot — really anytime you’re in range or stable or it predicts you’re likely to stay in range or anytime it thinks the insulin on board is going to bring you back into range (even if you’re out of range.)
I think that describes Omnipod accurately. Not Tandem.
This is perhaps starting the obvious, but it won’t always. If you’re basal is too high, insulin will build up and you’ll have plenty of lows and plenty of basal suspensions.
I don’t think the question is specific to Tandem or Control IQ. My general impression is that may people on MDI and, perhaps, a lot of people with pumps end up with a higher-than-needed basal. This works on high protein and, maybe, high fat diets because the short acting insulin we use for boluses runs out before the protein/fat has been processed.
The same applies to pumps; the basal can be used to cover the slowly digested proteins and fats.
I understand that but I do the opposite. I try to lower my basal to the actual amount required by my impaired glucagon response or maybe below because I know that my pump (AndroidAPS/Dash/G7) will correct for the elevated blood glucose.
I’m tempted to try an experiment and half my basal; enough to prevent DKA but not enough to cover all the glucagon being pumped out by my alpha cells. I’m simply not convinced my basal is low enough for the feedback loop to work properly.
As a relatively new pump user, I am a bit confused. What is the difference between turning on Sleep Mode and setting Sleep Schedules?
And if you use one, should the other be turned off?
Thanks
1 Like
Your sleep schedule just turns sleep mode on and off based on when you tell it you are sleeping. Most people sleep the same time every night so it’s easy.
Sleep mode allows for a lower target range, but also it does not give automatic boluses during sleep mode. Likely you don’t eat while sleeping.
Some people run sleep mode all the time because they want that lower target glucose. And don’t need to rely on auto bolus.
When I was on tandem, I ran sleep mode from 7 pm to 7 am. The time where I wasn’t eating. And it works pretty well like that.
You can also just turn it on and off as you like.
1 Like
I know this isn’t what you’re asking about, but bare with me.
I had a profile set up for high bGs that ran at 2x my normal basal, without changes to the carb ratio or correction factor. I only used it if the regular profile and extras boluses didn’t bring my bGs down. I was always careful to keep an eye on it and not leave it on for more that a few hours…except when I didn’t. Then things would go off the rails. Now that they put temp basals back into CIQ, I deleted that profile and use temp rate to be this better and safer.
What I learned from this is that CIQ is limited to how much protection it can give with high basals. When I’d neglect to turn the profile off, my bGs would swing pretty wildly. It would predict a low and turn down or off the basal. Then, as came back up, it would predict a high and start correcting with basal and bolus adjustments. Depending how low it initially went, there might be counterregulatory hormones confusing the matter. This would be based on a 2x basal, so it would over correct. Rinse. Repeat
Another pattern: after bolusing and eating, my bG would drop. I’d still have most of the bolus onboard, so I’d eat more. My bG would start to come back up, then go back down again and I’d have to eat still more. Thinking I’d gotten more sensitivity to insulin, which for me can happen when the seasons change, I’d go to adjust the basal and realize the high bG profile was on.
Back to your question…
It might do better with a smaller basal increase, especially in sleep mode. But watch out and if you see something like this, reduce the extra basal.
I decided for me, that throttling the basal is s safety feature. Using it to enhance control may work well as long as there are no extenuating circumstances. But it also narrows the safety margin. If you get sick or overestimate a bolus, it could cause trouble. I think CIQ works best when it’s setup to give the best control without CIQ. The corrections and safeguards are predicted on that.
It’s all a matter of degree and there is enough variation person to person, that the safety features are more conservative than you need and you may never have a problem running your basals slightly higher.
1 Like
I had my basal rates dialed in pretty well on my tandem. I did all of that by fasting. On a tandem it follows your basal settings and makes corrections from there.
Now I’m on Omni pods so it doesn’t use any programmed rates while I’m in auto mode. So I couldn’t change basal rates like you did on the tandem
The point is that once you can flat line your glucose while fasting and keep that up a whole day, it makes meal dosing easier.
After fasting 12 hours I would have a meal and figure out how much insulin I need for that meal.
That was how I finally got a handle on my diabetes.
1 Like