Is that the same thing as “extended bolus” on T:Slim? I have a T:Slim but am using it as a Dexcom receiver until I get trained Jan 6.
I was reading on bolusing with the pump last night and there are food bolus using units or grams, extended bolus and quick bolus.
An extended bolus is 1/2 of a dual wave. The other half is the immediate bolus; that’s like a simple bolus based on carbs or to correct a high BG. The dual wave concept combines those two modes into one function.
Before I went on an automated insulin dosing system I used extended boluses to dose for protein and fat. I separately used the immediate bolus to dose for the carb content of my meal. I didn’t like the way that dual wave boluses required using a percentage to split the dose between the immediate and extended portions, so I would, in effect, accomplish the dual wave in two consecutive separate steps. I do know, however, that people successfully use the dual wave.
What I discovered with the extended bolus was that it was highly effective and easy to make changes that worked well. I don’t think many people use extended boluses but people on this forum are much more likely to.
Thanks for explaininging that, Terry. I have no knowledge of the t-slim.
The way I use it, which may be completely wrong, is to consider immediate carbs (say, 50), and delayed needs for protein and delayed carbs due to fat content (say 35g) and then enter 85 g of “carbs” with some of it as a delayed bolus: 60% immediately and the remaining 40% delayed — over the next two hours. This works with Chinese food, pizza, large protein-rich meals; but I’m constantly tinkering with it of course.
And a correction factor is automatically added or subtracted from the initial bolus.
Only one of those options adjustss how the insulin is delivered, the other 2 are just the current means to request a bolus. The third way, bolusing via your cell phone, is coming soon.
The first one you mentioned is the most common way to bolus, and involves using the bolus wizard to automatically calculate your exact dose, and customize how it’s delivered. If you have good CGM data, your BG will be automatically filled in for you. You can also enter the amount of carbs you eat. The pump then uses your settings as well as any insulin on board to calculate a dose for you. You can also just type in whatever number of units you want, or you can override the calculated dose and type something different. (I often add 2 hours worth of basal insulin to the bolus dose, a technique called “super-bolusing”.)
On the next confirmation screen, you have a toggle on/off option to extend that dose. If you leave it toggled off, the entire dose will be delivered immediately. If you toggle it on, you can further customize the delivery timing. While Medtronic favors presets like “square wave” and “dual wave”, Tandem’s touch screen means you can easily tell it exactly what you want and when you want it. There are two data fields. You tell it what percentage of your dose to deliver immediately, and you tell it how long you want the rest spread out over. The extended bolus screen is pre-populated with 50%/2 hours, the common “pizza bolus”, which delivers 50% immediately and the remainder of the dose gets dived evenly and delivered every 6 minutes for the next 2 hours. Yes, this is the equivalent to Medtronic’s “dual wave bolus”. You can change those data fields to be anything you want, though. If you were to select 0% to be delivered now, then you have the equivalent to Medtronic’s “square wave bolus”
“Quick bolus” is just a no input, no screen, no bolus wizard way of ordering up a dose. It’s a combination of button presses that allow you to order an exact dosage. I have mine set up to work on 0.5 increments. So to order a 3 unit bolus without pulling the whole pump out and turning on the screen, I do a long press to activate the quick bolus function, then 6 short presses (3 units / 0.5 unit increments = 6), then count the vibrations as the pump repeats the request back to me, then finally one more long press to confirm. This only delivers an immediate bolus, as there’s no way to extend boluses this way.
That’s not exactly how it works. With Tandem, it’s entirely customizable, but most often it’s just like the dual wave. You tell it what percent to deliver now, and what percent to deliver over an extended period of time. Your “half the dual wave” comment is only true when one tells the pump to deliver 0% now.
I know that being type 2 DM and doing some kind of daily exercise as well as being quite active at 71 will make a difference. Insulin resistance/sensitivity does whatever it want, My total daily insulin is currently 32u to 35u with an odd basal:bolus of 79%:21% instead of the usual for T1DMs of near 50%:50%.
I had to come up with my own dosage, u per carb grams and correction factor.
Thank you for both your informative posts. 
You will need to change your correction factor and basal rates.
I don’t know why but they were different for me going from injections to a pump. They changed again when I switch pump manufacturers.
The biggest shift was going from Medtronic to Tandem
But once I got it going, it’s been a great system.
I don’t doubt that, Timothy. When I started MDI back in January, I had to do a lot of tweaking. I had been on 30u Lantus for several years split 2/3rds at night and 1/3rd in the morning. I was also on 2000mg Metformin. I had 2 big problems when I started Humalog. 1. A big rise 3+ hours after lunch, not other meals. 2. Any exercise caused a steep drop after 15minutes.
Reducing the Met to 1000mg and splitting the Lantus into 3 doses of 10 morning, 10 and hour before Lunch and 5 before dinner. Yeah this meant I was injection 6 times a day, not counting any corrections. This has worked very well for me. I don’t have a big jump after lunch and pretty straight line nighttime levels without a lot of hypo alarms.
From what @Robyn_H wrote, I could probably have done divided the lunch bolus into 2 doses. With the pump, I may find that Extended Bolus feature useful.
It is so much fun living with a dynamic think like diabetes. 
I’ll add a couple of tweaks to your good description of bolus options with the t:slim.
At least two things are different depending on whether or not you are using Control IQ.
One, the Dexcom number does not automatically populate for a bolus if you are not using Control IQ. Lately I have had Control IQ turned off most of the time and It is kind of a PITA to put in the BG number when you’re used to it automatically being there. #FirstWorldProblem
Secondly, if you’re using Control IQ, you can only extend a bolus for two hours. Without Control IQ you can extend it for up to 8 hours. I think that the philosophy is that Control IQ can control BG rises after 2 hours but people who use a lot of long extended boluses are frustrated with that limitation.
Although we’re just talking boluses here, one thing I really miss when using Control IQ is temporary basal rates. But that’s a discussion for another day….
I have a second profile that has a lower basal rate, called “weekend” for when I’m generally much more physically active. Control IQ still works when I’m on my weekend mode.
The one thing I like about temporary basals is that once the time is elapsed, you don’t have to do anything to get back to normal. If I change profiles, I have to remember to change back. But yes, that is a good option.