Sites changes and highs

Hello all. Thought I would post this again after a few years. I"m perplexed when I do site changes I usually get to look forward to a half of day of real high blood sugars. Sometime I give myself extra insulin but I believe all areas of my body respond differently. I’m at the point where I need to try to give an extra unit or two just to get started. My insulin requirements are about 25u a day. Anybody else have some strategies they employ?


I have the same problem. About 3 out of 4 changes my blood sugar runs high. Most times I just bolus until it comes within range. Other times I will inject 3-5 units of Humalog. I rotate sites, but I have been pumping for 20 years so I assume it is scar tissue.

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Right. So do you give yourself the extra insulin after insertion or just gradually during the day? I feel like part of the problem with diabetes is just finding good absorption as technology does not seem to address this is of diabetes management.

No, since it doesn’t happen every time I have to wait and see.
Every once in awhile it doesn’t happen until 6-8 hours, which I don’t understand.

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Similar problem here. Different parts of my stomach are different. When it goes real high after a set change it usually my fault on the inseration.

I learned exactly one thing from my pump trainer: That new sites need to be flooded with insulin before they start to absorb properly. She told me to fill my canula with 0.7u of insulin, despite my cannula length only requiring 0.3u.

I’ve long since switched to a full 2 units. I use the “fill cannula” option on my pump so it doesn’t register as IOB. On my t:slim X2, this means doing the max 1 unit, twice.

Also, keep in mind that if you don’t change your site until the last one is toast and your BG is already starting to rise because the site isn’t absorbing insulin anymore, the lack of basal received will affect you for 2 or so hours to come.


Maybe for some people, but that doesn’t sound like a great general principle.

It’s actually becoming a well-accepted principal. It’s the amount your body requires that is debatable. 2 units works well for me, but someone else might only need a half unit.

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I have this issue too. I have pretty much solved it.
I can’t say I know why though.
When I change my set, I leave the old one in. Start pumping with the new one. Then I remove the old one after several hours.
I think maybe removing the set allows the insulin in there to leak out or just not absorb with the change in pressure.
Like I said I don’t know why.
However I don’t have the issue anymore when I leave the old one in a while.
I learned this trick 10 years ago and it still works for me.

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I was surprised Tandem training said to do 1 unit fill cannula, when I always did 1.5 or 2 on Medtronic.

So on Tandem I just do repeat fill cannula to get it working better, depending on cannula length. Also tried keeping old one in, but did not find it making a difference.

You should fill cannula the same as your cannula length. There are several ones. The idea is to just fill it not to actually inject any insulin.

So if the cannula is .3 you give 1 or more units?

@Timothy It makes sense to keep the old infusion set at place. Some of the remaining insulin (~2u) inside the infusion tube somehow find way to leak into tissue without being pumped. This would supplement the absorption issue at the new site.

I have similar issues in certain heavy used sites. I find out only after 2 hours post-meal, the BG doesn’t drop. Your experience gives me the following idea that I plan to try from now on:

  • After the new infusion set inserted, I will keep the old infusion set for several (x) hours (x=2/Basel).
  • I will move or keep the tube anchor point higher than the injection point, so that the remaining insulin could gravity-flow to the injection point since there is no pump to push them in. Hopefully, the gravity will allow portion of the remaining 2 units insulin flow into body.

I can’t look it up on my pump but. I use 6 mm cannulas they are put in on an angle almost parallel to my skin. I think it’s .7

I use XC 6 mm sets, and have tried the 9mm.

This is Tandem instructions for XC.
U-100 insulin:

  • 6 mm: 0.3 units (0.003 ml)
  • 9 mm: 0.5 units (0.005 ml)

On new insert, I do .5 fill for 6mm, and if BG is high, may do additional amount.

I have a strategy that I use that seems to work for me, but I can’t really explain why. Here goes. I also leave my old site in for at least an hour before removing it. However, I don’t use the new site for the first hour or so. I use the Sure-t infusion set by Medtronic. After filling the tubing, I separate at the tag part that you unhook to take a shower and connect to the old site. Then I attach the tag part into a new site. I feel like it is letting the new site get a chance to get settled in. In that window of settling in, I just use the old site.
When I do switch connection, I will give .1 like others have said. If my new site is in a low absorption location I may use a syringe for the first bolus, but basal continues as normal.
An extended bolus for protein and fat are with the new site. I hope this makes sense. It works for me and has cut out some of the highs with a site change. However, not everything everytime with D is predictable.

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I have the same issue. I increase my basal by 95% (which is the most the Omnipod will allow) for 6 hours immediately upon putting my pod on. If I start going low, I can always cancel the extra basal. Has been working for me so far. Steady and can be cancelled.

I have this problem too. Today, for example, got way past my ok zone because of a new site (in my backside) Up and up my BG went. But after I walked my dog, things improved. Use that muscle? Who knows, but thanks for bringing this issue up. I’m kinda out of new real estate, and anxious about what comes next.

For me personally I do it just before breakfast works for me as then I’m doing a bolas for breakfast. This is what has worked for me for 30 years of pumping. I am only 27 units a day.

I came off the omnipod for this reason. It was so bad, I couldn’t take it. It is also based on location. Stomach fastest, arms second and butt forget about it! Hours to a day! I also found a 90 degree steel needle will get in fast than a cannula at a 30 or 45 degree, This is also why the pods didn’t work.
I fortunately went on Tresiba and rotate one month respectively each thigh and butt cheek. That long acting insulin takes 3-5 dats to get working but then I am gold for the month.
Pay attention to the cannulas and see if that helps!