I’ve been on an insulin pump for about 13 years now, and I love the convenience of being able to dose insulin without additional injections, and to create multiple basal rates per day. However, I’ve long had problems with absorption: if I give myself insulin by pump, it can take more than an hour for it to start working. It appears that some sites are particularly prone to allowing the insulin to pool right under my skin. When that happens, the insulin just sits there, unabsorbed, until either hours pass, or I do some sort of physical activity that engages that part of my body — in which case all the insulin will kick in at once and I’ll often go low. Sometimes the issue is a kinked cannula, but more often than not, when I rip out the set in frustration, it looks totally fine.
It’s extremely frustrating, especially when there’s no explanation for why the insulin isn’t absorbing. I used to have a doctor who refused to believe this was happening, which drove me even crazier (note to doctors: patients don’t usually just make things up) — and then I heard someone from a major pump manufacturer talk about how big of a problem this “pooling,” as I’m calling it, is, and how they’re trying to figure out a solution. I found it affirming to know that I wasn’t, in fact, crazy, and that this is indeed a real thing. (It’s sometimes caused when your site is sitting in scar tissue, or when your body’s immune system starts getting active around the site where the cannula’s inserted.) I’m glad people are working on it, because until absorption can be made more consistent, I just don’t see how an artificial pancreas system could work.
In the meantime, I have come up with a solution — albeit an inconvenient and annoying one — of my own: I have started taking my mealtime insulin by injection. I still use my pump for basals (I will never go back to long-acting insulin if I can help it!). And I occasionally take corrections by pump, especially in the middle of the night. But for breakfast, lunch and dinner, I’m back to needles.
Believe me, when my endocrinologist first suggested this to me, my stomach dropped. Injections are a huge pain in the ass (or stomach, as the case may be). I do not like this arrangement at all, and I’ve already run into problems when I forget my pen travel kit at home and am forced to bolus by pump anyway. I would very much prefer for there to be a way to consistently get my insulin boluses to work correctly when delivered by my pump, and I’m already dreading having to convince my insurance company that it should be covering two different forms of the same insulin.
But for now, this is turning out to be a much more effective — if annoying — technique. For the most part, if I give myself insulin by injection it starts working in the 20-30-minute timeframe used to advertise it. I have only had one incident where it didn’t work at all for three hours (only to have my blood sugar crash as soon as I went to the gym). I’m seeing less variability in how I respond to the same bolus. And as a potential bonus, the inconvenience of injections has also helped me refrain from snacking throughout the day and from eating more than I anticipated at a meal.
I’m not enjoying this new system, but at least it removes one variable from the multivariable equation that is blood sugar management.
I may mention this “technique” of boluses via injection and basals via pump to my endo. I think I get “pooling,” wherein the insulin NEVER gets absorbed. Where it goes, nobody knows! As Catherine mentions, when I pull the site, it looks fine. Due to this problem, my high BGs are higher than they ever were during 35 years of injections. (I have only ever “pumped” for 7 years and, BTW, my endo. makes all her Type I’s change out their infusion sites every 48 hours.) My question to Catherine is whether she disconnects and lets the amount of insulin… Read more »
This is a great article. I also have this problem. I always use my stomach, but have found if I stick to changing cannula every 3 days that helps and moving as many differant places as I can helps also. lets face it though activity is the biggest key to diabetes.
I have trouble with infusion sets too. (I wouldn’t describe the problem as “pooling insulin” but it is as good of description as any.) I use Medronic Silhouette infusion sets and my failure rate is nearly 20%. (I order extra infusion sets with just the cannula when I need to replace just the infusion set without the reservoir.) I have always blamed scarring in my belly where I rotate the infusion sets. I’ve experimented with different types of infusion sets (shorter cannulas, 90° cannulas, inserter devices) and have had some but not great success. I am considering switching from Medtronic to… Read more »
An endocrinologist I used to see warned me about this. It’s partly why I avoided going on the pump for so long. Three years post pump, I haven’t had any major “pooling” issues. Though there is an area on my hip that I find suspicious, so I try to avoid it. (Also because having my site there makes it uncomfortable to sleep on my side!) Anyway, you are not crazy. While it must be super annoying to manage with a pump AND shots, it sounds like you’re doing what’s smartest for your body. Kudos to you.
Great post. The occasional “missing insulin” problem has long plagued me (pumping since 2001) after a meal or correction bolus. While I’m not glad to see someone else experiencing this issue, I’m glad I’m not the only one who wonders where the hell the insulin went.