Omnipod PDM failure

So, my new pump is asking me to enter duration of insulin action.

Does this mean for correction or meal bolus?

Both. You only use one kind of insulin, and this number applies to both basal and any kind of bolus. I have mine set to four hours. Once you set it, you usually don’t ever need to think about it again.

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I am kind of curious about the title of your post - Omnipod PDM failure

Was there a failure? What happened?

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This is from the University of California, San Francisco diabetes education site. They specify that the duration of insulin action (DIA) for the three main types of rapid acting analog insulin ranges from 4-6 hours.

I recently updated my automated insulin dosing system app and the programmers have concluded that rapid acting analog insulins (Novolog, Humalog, and Apidra) use a 6-hour DIA for best loop results.

John Walsh also believes a 5-6 hour DIA works best in pumps. Here’s his take on DIA. He also explains how to test your DIA.

Thanks everybody. I’m going 4.5 hrs, temporarily. Until I have a moment to explore it further. I don’t use a bolus calculator, so this may not be really important for me to set. ???

@Eric2, I have had this pump for 5 years, it just finally kicked the bucket. I can get you the error code that showed up on the PDM (reciever) if you like. I don’t have it in front of me just now. But, efforts to reset it failed. Alarms went off - that whole routine. I had surprisingly little difficulty getting some basal in vials. Only took a few hours.

I was wondering about it because you had PDM failure in the title but then were talking about duration of insulin action.

If you manually look at the IOB as displayed on the pump and take that into account mentally when figuring out your next bolus then it would be relevant.

As I see it, IOB is what it comes down to. Whether using the pump bolus wizard (or whatever they call it) or using your own noggin - no diff. You still (likely) use the IOB as input. I think this is why it seems that the “Insulin Duration” (which has different names on various pumps) may need to be different across different pumps even for the same person using the same insulin type. The various Pump companies would appear to use proprietary algorithms to calculate the IOB at a given time.

The academic or theoretical Insulin Duration is IMHO a useless number from a practical standpoint. Which is not to mean it is not still academically interesting.

We need to configure this setting (Insulin Duration) on our pump which will give us the most accurate IOB (Insulin on Board) (which also only accounts for Bolus - not Basal) so as to enable us to most accurately calculate the best Bolus NOW whether using our noggin or the wizard.

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To the point raised by @Eric2, would you be OK with a slight thread title revision to reflect the main topic discussed in this thread which seems to be about the duration of insulin action on your new pump? That would probably be less confusing. BTW - Is your new pump also an Omnipod where you just switched to a new PDM or did you switch to something entirely different?

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Sure thing, guys. I understand your confusion.

They just sent me a new PDM. I mentally calculate my insulin on board, so it might not be a super important setting for me, but I might as well set it incase I ever use the bolus calculator.