Spooky occlusion: when do you switch?

Last night we had a difficult pump event. His pump site was about 36 hours old. Around 1am, my son’s BG started going up. After a major correction, he went down, but not much, then started on an unstoppable climb until 4am, when we briefly started going down, before going up again. Shortly afterwards, we had an occlusion alarm.

Numerous times during his climb, I considered a pump delivery issue, but when I saw the two short decreases I assumed I was wrong. When I talked to Insulet after changing the pod, they told me that you occasionally get some insulin deliveries even on the way to an occlusion.

It was very difficult to bring my son back down, which tells me that most likely it had been mostly without basal for a while, and past corrections had not made it through. I should have switched sites earlier.

When do you decide in the middle if a site session that you need to pack it in? Obviously, the MO for this situation (middle if a site session) is different from that of a site session initiation, where the infusion site health has not been established.

Michel, this is a difficult situation to diagnose. We have had so many of these on day three, that we now change after two days, which has mostly resolved the situation. My son also carries a pen vial of insulin and a couple of syringes in his meter case, because when we suspect a site, we just go ahead and inject the insulin instead of using the potentially compromised pump site. Since dealing with the aftermath is difficult as you have found.

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i usually decide to pack it in after 2 attempts of bring the BG down and getting little or no result. also, sometimes, i will test out my insulin first to see if it is bad by giving myself a correction shot. i like to rule one thing out at a time so i know better what i might be dealing with. generally, though, after several unsuccessful pump bolus attempts, i call it a night, bag the experiment and replace the infusion sight.

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There are a few possibilities. Depending on the alarm, the pod either detected an occlusion at the site, or it can be that it detects a delivery problem internal to the pod. The message you see on the PDM is very generic. You have to ask Insulet specifically what the alarm code means. I have a bunch of codes. If you want to share the alarm code you got I can look it up.

The other problem is that there can be a large passage of time before you get an occlusion alarm. I have done manual testing of this to see. I plugged up some pod cannulas and kept bolusing to see how long it would take to get an alarm. Sometimes over 4 units before I got an occlusion alarm.

If that was just basal at night, that could take several hours! So the occlusion alarm is troubling, in that you can possibly be without basal insulin for a long time before you hear it. At least with bolusing you would know it much sooner.

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We have a rule of thumb. If we suspect occlusion after a decent bolus with little to no improvement of BG (in around 1-1.5 hrs), then we give a manual shot. If the shot shows good responsiveness, then we can surmise an impending occlusion from the pump. If not, then there is probably something else at play.


How did you do that? Very enterprising!


I tried it a few times to test it. After removing a pod, before deactivating it I sealed the cannula tip with epoxy. Then I bolused in small increments and kept track of how long it took before it alarmed. :slight_smile:


We had a recent “is it an occlusion?” moment the other day, but after consulting with @Eric via text, I realized it was probably an impending illness. Your suggestion would be smart - to switch the site by using a pen to test out the bolus.


This thread is a mine of great ideas!

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I tend to change the site out if two or three corrections have no effect. I also change it out if there is itching or irritation at the infusion site (which indicates my body is reacting to it and it’s likely not absorbing well). I also have a blood ketone meter, and if blood ketones are high along with a high BG (usually I feel nauseated) I change the site immediately.


i swear on my life that this is a true story:

yesterday i read your post and i responded, thinking to myself, at the time, “thank god that this hasnt happened to me in a long long time; i feel so badly for you.”

well, i’m certain that you can guess what happened way too shortly after that to make me wonder if i put the kibosch on things :wink: .i was having a great day, BGs perfect flat line, and had been for a long while. but 2.5 hours after eating a NO CARB dinner, my BG went from 70 to 195. OMG. thought i should re-wash my hands and re-test. same answer. couldnt figure out what was wrong. i unplugged from my pump site and ran some insulin through the tubing to make certain that it was coming out and delivering properly; no problem there. so, i plugged myself back in and did a correction bolus. waited 1 hour, tested, NOTHING. not even a budge in the right direction. so i bolused again. waited another hour, tested again. and on and on. nothing. but, by midnight, i had come down to 150 and figured i would give myself 1 last correction and then go to sleep. (since i had in fact come down to 150, i figured something was working, and i had just opened a new vial of Novolog, so i doubted that it was my insulin.)

woke up in the middle of the night and tested. i had come down to 100. phew. then i bolused for a VERY low carb bfast. 2.5 hours post bolus, my BG had shot up to 185. WTF??? so i figured that i would take a correction and see where it went. i had the exact same problem as i had the night before. finally, after 3 unsuccessful tries to bring my BG back into range, i pulled the entire sight out, changed the infusion and essentially re-did my entire pump. did a correction, and within an hour, my BG was coming back into range.

as i write this now, my BG is 90. phew. what a PITA. but what a coincidence.

hope you’re doing better today :blush:


Like DM, I read this thread yesterday and today, wham…first ever alarm that didn’t signal the POD was expiring. It was 30 hours into a new site, no jostling, bumping or unusual exercise that would have caused it to dislodge.

I removed the deactivated the POD and when I removed it there was more than just a little bleeding from the site. I just assumed that was the reason for the alarm so, when I called for a replacement, I didn’t think to ask Insulet what the alarm code meant and the rep didn’t explain it.

Eric, is the Pod alarm ref# the code that can tell why the POD failed? The code was 19-00800-06151-080.

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Static electricity.

Your pod got zapped.

If you see this a lot maybe try different types of sheets, or a humidifier will reduce static, or spraying fabric softener on the carpet can reduce static electricity and
may help.

Oh, yes, I didn’t answer your question. That code is what you can give them to tell why it failed. They will tell you static.


This sounds awful, and I’m sorry it happened to your child. Everyone provided excellent feedback, but I wanted to add one thing that may or may not be a problem in the future for you (I definitely hope not!).

I’m currently using MDI, but I used to be on a MiniMed pump (I forget the model, but purchased about 6-7 years ago). I’ve never had an “occlusion alarm,” so perhaps those weren’t in use with the MiniMed that I used? If my site was no longer able to pump insulin, I would get a “motor alarm.” Anyway, the motor alarm rarely occurred, but I still had trouble with my site not absorbing insulin properly. On one occasion, my blood sugar began rising and I tried to correct for the rise. Nothing happened. I tried correcting again, and after no response, I chose to change the site. Once I changed the site, I corrected for the then very high blood sugar, and my blood sugar began to fall. Then I got a rapid fall alert on my cgm. After awhile, I realized that the rapid fall was a serious cause for alarm. I drank the carbs I had (gatorade) and went to my work snack bar to get additional carbs in case the fall didn’t abate. This became a serious emergency where I had to start guzzling all glucose in sight and an ambulance was called. I never lost consciousness, but it was a horrible experience. This was largely the reason I switched to MDI.

I’m not trying to scare you, but I think Chris’s suggestion of injecting insulin when you suspect a pump malfunction is very wise. My guess is that in my situation my site was “working,” but the absorption was occurring quite awhile after I bolused.


Thank you! I hadn’t thought that static electricity would cause a Pod failure but it makes sense. Interestingly enough, last week we replaced our whole house humidifier after it bit the dust (the one attached to our furnace). The humidity level in our house is now back to normal. And we have no carpeting in our house either.

But I do suspect the culprit is the current US Midwest weather. The high temp here barely broke 5 degrees F today, with much of the day around -4. I appreciate the info.


Michel, like others have shared, the few times I’ve changed a site early due to poor absorption I did so when the only way to get my BG down and into range was a correction with a syringe.

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Do you think static could zap a Dexcom transmitter?? Mine failed yesterday while I was hanging out in my husband’s home office–dry, electric heat plus carpet.

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@daisymae, @Millz, these are crazy coincidences!

This is our first “progressive” occlusion, but, thanks to everyone on this thread, I am a lot less concerned about the next one.

It is a bit spooky to think of how close we can be to a DKA track sometimes.


@Chris, @Katers87, thanks for the input: using a pen injection as a way to test reaction to insulin seems the standard way to go from here on if we have any concerns about progressive occlusion.

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I guess most anything is possible, but probably not a very likely cause. If that happened to Dex’s often, we probably would have heard about it by now.

What did the Dex people tell you about the transmitter? Do they have any ideas?

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