I’m curious about how much insulin I’m using. I’ve collected a very small amount of data, nowhere near enough for conclusions, but I want to ask what some others think.
I use a Tandem Tslim. I buy novolog by the 1000 unit vial. I opened a vial on August 21. I kept track of when it ran dry and I opened the next one Sept. 15. That’s 26 days, counting both days at the ends of the duration. I then went to my Tandem data site and found that in that period the pump software says I only used 630 units of insulin at an average daily rate of about 24.2 units per day. That means that after going through an entire 1000 unit vial I actually put less than 2/3 of it IN me!
That doesn’t make sense to me. I know I use 12± units to fill the tubing each time I fill, and I did that 6 times in the duration. I know I used a bit squirting out air from syringe each time I filled a new reservoir. But still! From an economic point alone not getting more than 1/3 of the vial into me aggravates me!
Comments, anyone? I’m really confused where the insulin all went, if the data on how much I used is right and my dates are right too. Actually injecting only 630± units in 26 days and having to throw away a 1000 unit vial at the end doesn’t make sense to me at all.
I plan to continue gathering data on how long a vial lasts and how much the software says I actually used, but I’d like to hear from others on this too, if anyone has any comments on where did it all go if it didn’t go INTO ME?!
Difficult to know exactly what you are doing minute to minute, but I wonder why you are using 1000 unit vials. I didn’t even know they made those.
For me I use 100 unit vials and it’s easier to track my usage.
I used to have a tandem pump and although it says it has a max volume of 300 or 200 units depending on which one you get, it holds a lot more.
You mentioned the tubing and the priming, but also the cartridge does not run dry.
Get some 1 ml syringes and fill the cartridge with that. You can easily figure out how much you actually load and how much it says you have.
Even on my Omni pod that says it’s max 200 units, it actually takes 250 units, and 20 units wasted with priming. Which seems like a lot with almost no tubing.
But even after the pod thinks there is no more insulin, there actually is more insulin. And you can keep it going long after it says it’s empty.
The problem with the tslim is that you can’t see the cartridge contents. It’s actually a plastic bag inside there and there is no way to use all of it.
Pumps waste insulin. It’s unfortunate, but it’s a reality
Could the OP be mistaking a 100 unit vial for a 1,000 unit vial, which I doubt exists? He should recheck and recalculate. Yes, there is some waste of insulin when using a pump, especially the Tandem x2. But not to the degree that he thinks.
Yes, the OP (that’s me) could be doing exactly that! The OP has always confused units and milliliters.
What I do know is that when I fill a Tslim reservoir I use their needle (which is marked to hold 300 somethings) and I put in just a little over 150 of whatever units (could be cubic feet for all I know) it’s marked in, or about 1/2 of a full syringe. And I typically do that about six times per vial. So I use about 900-1000 of whatever units we’re talking about and the vial is then empty and I need to open a new one.
The point isn’t my misunderstanding of units although I freely admit I don’t get it right! My point is, I use about 1000 somethings per vial and the Tslim software says about 630 somethings of insulin got into me. So where’d the rest of it go?
Yes, there IS a lot of waste of insulin when using a pump. I use the Tandem x2 and try to use up every last drop in the insulin vial. Of course, that is impossible. There is also the insulin left in the tubing which some users remove with a syringe and reuse. There is the amount that is used for priming and also the insulin that is left inside the plastic bag in the cartridge. I would say that I use about 2/3 of the insulin that comes in the vial. A tremendous waste, indeed. But I know of no way get around that.
Are we confusing reservoirs with vials? The bog-standard vial of U-100 insulin is 10ml of volume with each ml having 100 units of insulin. That works out to 1000 units per vial.
U-40 insulin has almost completely disappeared but was 400 units per 10ml vial. U-500 insulin in a 10ml vial is available and that’s 5000 units per vial. Many pens and I think some pump insuln are also available as U-200?
Insulin pump reservoirs are typically 1.8ml to 3.0 ml and will hold up to 180 (1.8ml) or 300 units (3.0ml) of U-100 insulin.
The OP has always confused units and milliliters.
My point is, I use about 1000 somethings per vial and the Tslim software says about 630 somethings of insulin got into me. So where’d the rest of it go?