November 27, 2006
Hyperglycemia and DKA, Insulin Pumps
Question from North Tonawanda, New York, USA:
My son has been using an insulin pump for a year. The past three times I have changed his site (in his stomach), he will be extremely high, 400s mg/dl [22.2 to 27.7 mmol/L] for six to eight hours after the site change and then it seems to kick in. We use Sure-T infusion sets. It seems like his body will not respond to the insulin coming through the pump until six to eight hours after a site change and then it will work perfectly until the next site change. I will test him before and after a site change and his sugar is normal, 100 mg/dl [5.6 mmol/L] or so. An hour after the site change, I will check and his blood sugar will have started to rise. I will administer a correction bolus via the pump and check 90 or so minutes later and his sugar will have risen more. I will then administer another correction bolus via pump and check again 90 or so minutes later. He will be even higher and have started developing ketones. This will continue for about six to eight hours and then, all of a sudden, it seems as if the pump kicks in and his sugar lowers and then for the next two days his sugar will be fine until the next site change.
Answer:
What I think is happening is that you are removing the old set and getting “leakage” at the site; insulin is actually coming out just like it does when you give an injection. I tell all pumpers to leave the old set in for several hours to be sure the insulin that was most recently delivered, be it basal or bolus, is completely absorbed before removing the old set. It seems like four hours is about the amount of time to leave in the old site. Let us know if this solves the problem.
NB
