Finally started pumping

I just registered on the website and this is my first post. I've got T1 and I had been using MDI before I finally decided to get a pump. My last a1c was 7.5 which is considerably high. I usually try to keep my BGs higher than 7 mmol/l at work simply trying to avoid lows. However, I often used to lose control and mo matter how much I injected, my BGs were around 12-15 mmol/l. So far with the pump my numbers are not in my acceptable range but now I use less insulin (12 units basal vs. 17 units of lantus per day). Plus, I:C ratio is 1:20 now vs. 1:15. Hopefully, with help from others I can bring my BGs a bit lower.

1) I need more insulin in the morning. I work shifts so I might wake up at 5:30am or 5:30pm. I noticed that it's not only in the morning (sunrise) but when I wake up my I:C ratio is 1:10. How long after I wake up this ratio remains the same before I can use my normal 1:20?

2) My healthcare prof also changed insulin sensitivity to 3.0. Does that mean that 20 grams of carbs (10 in the morning) raise my BG by 3 mmol/l as well? Or it's only 1 unit of insulin lowers BG by 2 mmol/l?

3) When you change infusion sets and lots of insulin left in reservoir, do you dispose insulin or top up the reservoir?

4) How long does novorapid really last? I selected 4 hours by default.

These are only a couple questions. Hopefully, I will get some response.

Thank you in advance.

I’ll start. Insulin in the pump is subject to body heat, which degrades it. So the usual rule is not to mix old with new insulin.

Insulin duration can vary by person, but between 4 and 6.5 hours. You can test: be stable, take a small amount of insulin, see when your sugars stabilize after dropping, repeat. A CGM is hugely helpful here.

Hi Vladi, I'm just starting on a pump also. I hope it will work for you- it takes time to adjust to it, I was told it can take 6 months. I was just wondering about one of your questions also- I filled the reservoir with more insulin than I would need for a 3 day period due to issues where I had to refill/prime the tubing and I'm wondering now if I can simply change the inset and not the cartridge. I just emailed that question to my cde. I wouldn't add fresh insulin to older insulin though.

I have my duration at 4 hours but I know on mdi it can sometimes be much longer than that. I think all of these things are different for each person. My doc/cde changed my insulin sensitivity/correction factor to 75 at first, but it is now 70, 60 for various times of day. novolog has lasted much longer than 4 hours in me at times.

Medtronic will send me CGM when I get used to pump first. Four hours seems to be working ok for me except 2 hours after meal my BG raises to 11-12 mmol/l and only after 4 hours it lowers to a number I planned for. I need to figure out how to avoid those high numbers 2 hours after meal.

Keep in mind that number doesn’t change how the pump delivers insulin, it just affects how much insulin the pump tells you is still in your system after X hours.

Addressing that peak will require bolusing earlier before starting to eat. 20 minutes for sure, but some of us do as much as 45.

An advanced technique is the super bolus, but first you should master pumping.

And some peak is unavoidable.

Thank you for the reply. Let me know what your cde told you. Can you use the same reservoir 2 times though?

Thank you! I will try bolusing 30 mins before.

You're welcome- well if you just use the same tubing all you need to do is put a new inset in, reattach the tubing and fill the new cannula. I had to do that when I had a bent cannula which stopped insulin delivery or reduced it anyway, again with no occlusion alert from my pump. My cde said that was due to me using very low levels of insulin. Still I think it should alarm even if insulin flow is reduced or low because my bg climbs very rapidly without basal. I'm not sure though, I will let you know- I don't want to waste all of this insulin, but I wanted to have more of a buffer for other issues and running low before change if I don't have time to change it right away.

Make sure you ask your cde/doc though. Each pump is different. For mine I had to still stop insulin flow to fill the cannula as I recall.

I change my sets every two days and I get 4-5 days out of a reservoir, so I often just change the set and not the reservoir/tubing. I was told that Humalog and Novolog are "ok" for up to 7 days in a pump, whereas Apidra degrades after 48 hours. The only downside I've found is that I throw away a lot of unused tubing...

Amy, someone at tandem told me that you can get just the inset without the tubing for some of the insets anyway so that way you don't waste the tubing. Or you can save it and then if you have a tubing issue maybe you can use them then.

I don’t think the site alone is available for the metal sets…otherwise that would be awesome. As it is now, if I can keep track of the tubing, I do try to use it…but with 3 cats in the house things have a way of moving and becoming less than sterile :stuck_out_tongue:

I can order my Sure-T sets either with tubing or without. i usually order half of them with and half of them without, and change the tubing every other set change.

on #3, once you figure out about how much your TDD is (total daily dose), you can refill the cartridge (reservoir) with the amount you need for 6 or 7 days. This is what I do. I change the cartridge on day 1 with a tubing change, then 3 days later, just change the cannula and give myself about .5 units to fill the cannula. My educator says the tubing I use (accu-chek ultraflex) is designed to keep the insulin good for at least 6 days.

Huh…I’m not a mini med pumper and I order through animas…so maybe that’s why? I’ve never seen the option on the site, so I never thought to ask…I definitely will next time!

Hi Marie,

Can this be done on any pump? I spoke with Tandem today and they said to change the whole reservoir etc. every 3 days with novolog. I don't see why it would degrade in 3 days only from some body heat, but I'm not sure. I filled the reservoir with a lot more than I need this last time due to all the issues I was having with having to refill the tubing.

The t:slim has a plastic bag insulin reservoir (which allows is to be so slim), whereas I believe competitors' reservoirs are glass vials (at last some are, not sure whether that applies to all others). Insulin degrades more quickly in plastic, not sure why, maybe air permeability? Tandem's official policy is to swap out everything every three days. But we're talking about gradual deterioration of insulin, not some sort of binary good-to-bad process, so that's almost certainly a conservative recommendation. If insurance covers it, I see no reason not to stick with the recommendation. But if the dollars come out of your pocket, it might be worth experimenting, though detecting gradual insulin deterioration will be hard.

I'm more concerned about the insulin sitting in my tubing. My short (23 inch) tubing contains about 16 units of insulin. My daily basal is only 9 units, with a bit more than that of bolus, so my insulin is sitting in a plastic tube, against my skin, for many hours before it gets delivered.

Thanks Niccolo,

That makes sense about the plastic bag.

I think I may just leave it till tomorrow. I'm not sure what to do because I have had so many issues and I don't want to deal with another episode of high bg when I teach tomorrow. I had a bent cannula where the pump didn't warn me and my bg went up rapidly which was stressful. My cde said that since my basal doses are so low the pump won't warn me of an occlusion for that and a tandem rep agreed- unless I take a large bolus I will get not warning I'm not getting insulin for things like that. I'm taking about the same as you now almost 8 units still with some corrections and temp rates too, I'm not sure if that is added in or not.

I never thought about the tubing issue, they told me there is 1 unit per three inches of tubing so I assumed there was 8 units in the 23: tubing if you include the part before the luer lock. I spiked up a bit after my brunch and a basal correction and correction brought me down so I think it is still good so far.

I think my insurance will pay for it but I have only just started with the supplies and using older penfills to use my oldest insulin so I'm not sure.

If you leave the tubing outside your clothes most of it won't be subjected to extra heat and kinking- my trainer said she has had occlusion alerts from kinks and she just adjusts the tubing when that happens.

my cde emailed and said it is ok for me to just change the inset this time so that is what I'm going to do.

My reservoirs are big fat plastic syringe I'm not sure that it's just that it's plastic...maybe it's the kind of plastic?