Omnipod - Correction Factor and Glucose goal range - which has biggest effect (in your real experience)?

Hi all.
Since November I have played with all of the settings on this pump. I recently did a reset, and began again with the previous most aggressive numbers I had dialed in, and that still didn’t seem to give me enough basal. I am now three or four pods in after the reset. I am feeling in this last pod, especially, that there are significant changes going on, and that the algorithm is doing more, but now that leads me to think of ramifications for insulin carb ratios and other things. But without even adding that, if you have an opinion and can share your experience for how much you may have adjusted your correction factors, and or the goal range, and the effects, I sure would like to know. And even just which you feel, if you had to choose, affected the pod’s performance for you the most. I am trying to get a better sense of the algorithm’s working. I have my opinion and will be interested if others experienced the same. Thanks!

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The OP5 algorithm is pretty simple in terms of what we can control. How much or how little insulin the Adaptive Basal Rate delivers is totally based on only two things - your total daily dose of insulin given as experienced by the last three pods worn, and your target glucose. That’s it. All those other settings only apply to mealtime coverage doses or when running in manual mode.

My advice to anyone who is managing their own care and struggling with the OP5 is to run it in manual mode until you are getting the kind of control you want and then for another 10 days. The OP5 is collecting that essential information about TDI while in manual mode. And if you can’t get the results you want in manual mode then the OP5 is set up to fail.

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Thanks for that info., @mremmers. I might be an anomaly here, or just some other variables are happening as always, but when I reduced my goal range to 70-140, it has almost seemed like I need to pay attention because microboluses have been twice as high (.05 to .1) and much more frequent. I had not changed anything else, so attributed it to this range change. I am liking it, though😁! And I do want to go to manual and tweak segments once I see what works for different times, but I am finding I do no know my own basal rate at all. To avoid overnight lows, would you suggest I just put in one rate for the day, to start, and use the rate that most closely matches what the algorithm is giving me, and then proceed to really fine-tune it? I was on 12 units of Tresiba, but on OP5, I get 8.3-high 9s, but OP5 pauses basal during eating, so that is probably part of difference, and at this point, when I forgot to change back to automated after trying a rate matching Tresiba, it was too much. Anyway, I may have answered my own question, but for those of us who have never done basal testing and don’t know, would the above method be where to start? Thanks as always!
Laura

You have to think of the OP5 in Manual Mode as a whole different pump than when it’s in Auto Mode. When I suggest mastering your blood glucose control in Manual Mode first it’s so you’ll know what your ideal settings would look like. We really do need to know those numbers otherwise you are trusting technology to figure it out for you and, well, that’s unreliable in the short term and a very, very slow process.

I don’t see the changes you made as resulting in that 0.4u per hour increase. Instead, the pod is using your TDI data to make changes. When the pod is “learning” you’ll see subtle dosing changes with each pod change. When you hear people say that they had a horrible first three or four months on OP5 in auto mode, then things got better, it is because it took that many pods for the Adaptive Basal rate to slowly get that more was needed and increase the allowed dose. I prefer to teach the pods not let them learn and that happens via Manual Mode.

Yes, basal testing is important. There are lots of articles detailing how to do this. I tend to like the short but intense way of basal testing - I start fasting at midnight, with my blood sugar at or close to 100, without food or coverage insulin on-board. Then I begin 24 hours of only drinking water - no food. (Usually ends up being more like 32 hours, or morning.) If at the end of that fast my line has been flat and in a good fasting range, I know my basal rate. If I drifted low or high at any point I call off the test, adjust my basal insulin dose as indicated, and give it another try in a week or two. This sounds gruesome but it’s really not. Drink lots of water.

Lastly, and I know I sound like a cheerleader for Manual Mode, if you use it to nail your settings before going into Auto Mode you’ll also be able to verify your I:C ratio as well. In Auto Mode it’s hard to tell if your I:C is right because the Adaptive Basal Rate is trying to correct errors in coverage dosing.

Good luck with your OP5 journey.

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@mremmers - Thank-you!!!

I totally agree and this makes sense. I am doing this back-assward and need to get into manual. Thanks for sharing how you do basal rate testing. I think I am struggling, even with acceptable results in OP5 use because of all these other things being askew until I get basal right. Thanks so much! Take care.
Laura

I have a different understanding of the OP5. I don’t know if it is the correct one but it comes from listening to the Juicebox episodes and the Loop and Learn Panel discussions and discussions with my CDE.

Sure it’s valuable to know how to manually use the pump for times when dex is off or your insulin needs are higher but it’s not exactly helping the algorithm. The system isn’t getting any better info during this time. It’s only using Total Daily Dose for this period. You would get the same even in auto mode. If it’s keeping you steady overnight there is no need to use manual while sleeping.

You need to bolus in auto mode to learn to work with the algorithm. From my understanding everyone’s carb ratios are generally more aggressive because the system cuts the basal when below target. If you’re blousing in manual mode you won’t get to practice. It’s a lot of time wasted. My settings are different for OP5 then from dash. I changed them on my second day when in auto mode. I have used auto from day 1. Only changing into manual when it wasn’t aggressive enough.

The reset is really only valuable for times when your basal has dramatically increased for a few days. ie sickness or menstrual cycle. It’s not going to increase your TDD for more the one pod.

I’m not sure where you changed the target to 70 to 140? Is this in Dexcom Clarity? The only target that the algorithm pays attention to is in OP5 110 to 150. If you feel unsafe at night then you can change the target to higher than 110.

Carb ratio, target range, activity feature. These are the only things that you can change. You can manually bolus corrections when needed to add to TDD.

Just my own opinion. I’m not a expert or anything.

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@Josie Thanks for the reminders you have provided, and the balance. BTW, You can change your glucose goal range on OP5 controller - it is under settings and right below reminders. I’ve put mine back to 70-150 on both clarity and controller, but probably not hugely relevant. Though I ultimately want to aim for good TIR in the 70-140 range. It was probably just a bunch of coincidence between OP5 behavior and my changing that last Friday. I suspect that after my reset and starting with more aggressive settings, as opposed to when I first got on it, it is closer to my needs at this 4-pods-in point than before. I am much happier with the OP5 since reset, so something happened to help.

And so relevant to your post here: I think I am making myself crazy with all of this and I have just gotten to the point of realizing I am sort of grasping at straws in search of perfection. Instead of immersing myself in so much of my own previous data and scrambling to get all my questions answered (and they are infinite!), I need to regroup and remember that OP5 is now doing better than I did for myself on MDI and that merging these two data bases of knowledge in my head when they are different beasts, to me anyway, is just using up too much of my time. I could follow the rabbit hole for a long time.

But, with your kind chiming in, I feel confident that I can just master automated and relax a bit. I found this site and just love that people can live so much better with technology than perhaps the corporations can grant, (through looping and finesse of manual, and now I am grateful to know it is there. But, my learning of just diabetes in general, and responses to the changes that can happen that are most healthy, needs to give me a good foundation before I waste time experimenting when I don’t even understand basics. I am, for instance, getting great help for how to exercise with diabetes. And now I can ask all the questions that my NP at the endo only seems to have generic, conservative answers for, or just admits not much is known (but in community, much is actually known). So, I am giving myself permission to slow down and try to live with all the unknowns, back off of anxious pursuit of immediate answers, and learn what works for me. Just knowing there is room to change-up how to do things in the future, if desired, is hopeful, but my enthusiasm to jump right in, just got me in over my head and I will slow down and master the steps before trying to leap over the whole ladder.

Your timing here is perfect and I am so glad you offered your perspective. It supports the notion that it is okay to use automated, especially as I learn how to pump, what interactions the ratios and settings have, and their results, and how best to use the pump. Then, I have room to grow into manual use and even looping. And I have time to absorb all of this knowing that I was surely ignorant of when I started the pump. I do love knowing how others handle their diabetes, so all of this is just such a giant leap from my previously limited world to draw from. Oh - I also discovered the Juicebox podcast, and love it, but I also have to limit myself on jumping into some of the bold with insulin stuff. Sometimes I am too fearless (read - ignorant) until I am dangerous and the can become fearful. Pausing and patience and assimilating is a better approach for me, and not my natural way. But I want to live and live fearlessly! 2.5 years in is really still not much time. Thanks so very much for offering your perspective. I definitely hear you and you have helped me. I hope you have a great day!
Laura

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I really think you don’t get it yet based on your comment. If you are in auto-mode and feel the basal settings you originally entered into the pump or even changes you’ve made to the basal settings since are causing you issues at this point, wrong. The OP5 stopped considering your basal settings when you took that first pod off. I would highly recommend you listen to the 3 podcasts, specific to starting the OP5, found on this podcast:

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I want to make a comment on the basal testing. Everyone has to do what works for them to figure stuff out. And we all have different ways of doing things.

But for a lot of people, when they are fasting, their basal needs are a lot lower than normal.

So doing basal testing to establish the right basal numbers - and doing it when you are fasting - means that those “right” numbers are only right for when you are fasting, but are not right for when you are just eating normally.

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The algorithm is collecting one bit of information from previous pods - the total daily insulin dose. It collects this information the same way to the same degree whether you were in manual or auto mode. It was a bit of misinformation that got amplified to be otherwise, which was unfortunate.

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That’s totally me. My basal needs are DRASTICALLY different when fasting. I have no idea why. If I skip dinner(once in a blue moon) I need 50percent less insulin for the entire night. I am LADA and still have a very small basal response left. Maybe even my sort of low fat vegan diet is causing a little insulin resistance. Or maybe fasting provides a greater insulin sensitivity?

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This is a very interesting topic!

There are a lot of reasons why our basal needs change. What you are seeing is not surprising.

We should create a separate post for this to discuss, so as not to hijack this thread too far off the original topic.

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Actually no…I wasted months trying to let the algorithm handle meal bolus in Auto mode. If a meal or my GI track (or whatever) requires an extended bolus the Auto mode will never learn how to do this, it has to be done manually. Using manual mode because it allows an extended bolus is certainly an acceptable way to use the pump.

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Slightly off topic since I use C-IQ, I find the Tandem extended bolus doesn’t work for me. I tend to have BG start ramping up 3-4 hours after a meal. So I do a correction bolus. I guess this could be called a manual square wave extended bolus.

Back on topic, it appears to me that OmniPod 5 would not be a good fit for people like me. Probably works well for some, OK for some and not so good for others.

I was hesitant about using C-IQ when going off of MDI, but I appreciate the basal reduction at night or during exercise. I use sleep mode go for night but stay on regular for exercise.

It’s too bad that we can’t get an extended trial of day 6 months to learn what works for us. They could send refurbished pumps and controllers to Endos. When one works best for an individual then they get that pump.

Probably too much to ask for.

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I don’t know about the OP5 specifically, but I can comment on this in general. The “goal range” for a closed loop algorithm is the BG values where you don’t desire any change to your BG. If your BG is above the range, the algorithm will try to bring it down. So if you had a range of 70-180 then the algorithm wouldn’t give extra insulin until the BG was above 180. If you then lower the range to 70-140, then any BG from 141 to 180 will now be getting treated with insulin, when it wasn’t before.

For myself, I have a single number for the “goal range”. For me, I’m not equally happy anywhere between 70 and 140. I’d rather be 100 than either 70 or 140, so I want the algorithm’s help to push me towards 100 all the time. At 120, I’d like the algorithm to give me a tiny bit of extra insulin. At 75 I’d like the algorithm to withhold a little bit of basal.

The goal range for the algorithm is different from the target range I tell Dexcom Clarity to consider “in range.” The closed loop goal range (or single number) is instructions for when the algorithm should try to adjust my BG. The Clarity target range is for me to judge myself on how well I’m managing my BG. (And the Clarity AGP report uses 70-180, which is what I show the endo so they can evaluate my BG “time in range.”)

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Well, the OP 5 has “Target Glucose” and “Correct above” which seem to be what you are talking about and I have both set to 110 (the lowest allowed). The range, then, I guess could be more about how to view data? Not sure about that. And probably as @mremmers has pointed out, nothing but tdi matters anyway. Much to ponder for sure.

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@Eric Thanks. I don’t know if I have it in me to do the fast thing anyway. I have planned activity and such. You still believe we can find our most-often-correct basal anyway, don’t you? And do you think I should try another way of knowing? I now have several set based on my variations of TDD over time and such - it has been giving from 8-10 with influences like failed pods and needing insulin on new pod to replace what it thinks I has, and the few times I ate 10 more carbs than usual. I am now try trying to discern interplay between basals and I/C ratios and have stayed in Automated and am trying the new tack of leaving it alone and seeing if it will fix itself in a not too long time. Seems I cannot leave this alone after all, because I do have such desire to master this knowing of what works best for me. In a few days, I am thinking of using my basal rate that matches whatever I find to work best on automated and hope for no lows at night. Between crazy bad dexcoms in a row and my own experiments, I have lost lost of sleep lately, but hoping if this dexcom stays true, and if I can stay good on automated for a while, I will actually be ready to not fear manual. Thanks for chiming in about this method of basal testing. Very helpful!

I deleted the following comment as I saw where this topic had been given its own item. Now I can’t find that item. So, I’ll just add this one short comment.

Basal insulin coverage, by definition, is used to manage the background metabolic need for insulin to maintain a stable blood glucose level in the absence of food. Once you add food, or exercise, you might need more insulin and give that under the guise of an Adaptive Basal Rate or additional Tresiba, and that’s great, but testing for the baseline metabolic insulin needs to happen in a fasting state.

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I’m not so sure about that. I want my basal insulin to cover the background glucose that’s released by my body (mostly the liver?) for “staying alive” energy when nothing’s happened that would change my BG: no special stress, or exercising, or eating, or anything.

If by “a fasting state” you mean I skip a meal and watch what happens, I agree totally. But if you mean something more like a 12-hour fast or a 24-hour fast, then I start to disagree. Because when I’m on an extended fast (such as prior to a medical procedure) my basal requirement seems to drop by about 50% because my body is not releasing a normal amount of background glucose, it is in a mode of “preserve glucose stores because it looks like we’re starving.”

For setting my routine basal, I want to use my routine lifestyle, not a 24-hour fast. I’ll delay a meal by 3 or 4 hours and watch what happens during that meal time in the absence of food and a meal bolus. But after 12 daytime hours without food, my body is already in starvation mode, so my basal needs would appear lower than normal.

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I really think we are on the same page here for the most part. I too consider the liver’s contribution important and that falls under metabolic needs, which is basal insulin’s job. And I see what you are saying about a long-fasted basal dose being lower when long fasting but, for me, that’s when I see the most glucogenesis, where the pancreas and liver both join the party to increase blood glucose levels. So using a 24-hour fast to determine my basal insulin settings actually gives me a slightly higher dose.

I only do a 24-32 hour basal test once every five years or so. I feel what I take away is reasonably accurate and worth the short-term discomfort. But that’s just me. I certainly wouldn’t put a kid through anything like that.

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