Omnipod malfunction- internal leak?

I’m interested if anyone has experienced the following problem. This has happened to me before a few times about a year ago, so it is rare, but others may have had the same problem.

Over the course of 3 days after changing a pod I gradually experienced much higher post-meal BGs, and corrections took 2-3 times more insulin bolus volumes, as well as running basals at +50% much of the time on the 3rd day. I could feel no leak at the site and no smell of o-cresol from the insulin. No illness and ate and exercised as usual.

I removed the pod and did not deactivate it. I programmed in a 3U bolus and observed insulin pumping out of the cannula as it should. Then I programmed in another 3U and pinched the cannula shut with blunt tweezers. No insulin was pumping out, and after the bolus was done, there was NO occlusion alarm. I again programmed in 5U and pinched tha cannula, and again NO occlusion alarm.

I have done this with “normal” pods and the occlusion alarm always sounds and deactivates the pod.

So my conclusion is that their was an internal plumbing leak that diverts the insulin flow from the cannula, but might also allow lesser flow into the infusion site.

Pods from the same lot appear to function normally.

Has anyone else suspected and documented this problem?

Below is a description of a similar, related problem I sent to the IP list last year.

Mark

On Jul 21, 2008, at 5:56 PM, Mark Yeager wrote:

I put on a new pod last night and woke with a BG at 218. Took 2.5 U bolus. Hour later was at 258. Another bolus of 1.5 U and no breakfast, off to work. 2 hours later BG of 250. Switched to using a pen thinking I had a “site problem”. This has happened before about 5 times since I’ve been using the pod for nearly 6 months now.

However this time I removed the pod without deactivating it. Observing the cannula I programmed in 5 U bolus. There was a slight air gap at the tip, and a clear meniscus where the insulin liquid could be seen. The meniscus did not move at all for about 2-3 units, then started moving, emitting a few drops, then nothing again for the final unit or so. The pump was “clicking” the whole time, and no error msg. I then programmed in 15 U bolus and watched again. After a few units the insulin started moving again, and then an air gap appeared at the base of the cannula. The insulin stopped emitting from the tip, then the entire cannula drained back into the pod!

Clearly there is an air leak somewhere in the plumbing, or the priming step was faulty, but there was no error when I filled and activated the pod, nor any error today.

Has anyone tried observing an active pod after having problems with BG control to see if it seems to pump correctly? I would suggest checking it out. This one is going back to Insulet for replacement and so they can do a postmortem on it.

Hello Mark,

I have had similair issue, not documented though. But I have taken four or five corrections with no results (or much later results). Same thing with meals, I never got an oclusion alarm or have tried what you did (tweezers). Just assumed the canula came out (couldn’t tell in the window though).

I’ve had similar issues, too, but it didn’t occur to me that there might be an internal leak. Next time, I’ll check it out.

Thanks for the heads up!

Janet

i had something similar the other night, but it was because of a bent cannula. no alarm or anything, even with the pod leaking.