Omnipod Loop needs to have a Prime operation

[itsmojo]

Some Omnipod Loop users would like to give additional insulin when starting a new Pod because of site absorption issues. If the user uses a bolus for this, the bolus amount counts towards the Active Insulin which is not wanted. A more desirable way to handle this would be to provide a general Prime operation where a user can specify an arbitrary amount of insulin to be delivered as a bolus that does not count towards the Active Insulin. Ideally this new Prime command could be used at anytime once a new Pod is ready and the prime bolus should behave like a manual bolus as much as possible (e.g., display in the home screen status line, be cancellable, etc) except that it doesn't count toward the Active Insulin. Having a manual Prime operation allows a user to easily adjust the amount given per site as well as being useful for other situations that a Medtronic Loop user can address using the pump's prime operation.

A long time workaround for this has been to take a manual bolus and then deleting the entry from the Loop's Insulin Delivery Event History and the Health app's Insulin Delivery log. A newer workaround available to deliver an extra fixed amount of insulin for each new Pod site in the current dev version of rileylink_ios is to edit the cannulaInsertionUnits constant which can be found in rileylink_ios/OmniKit/Model/Pod.swift to be a larger value than the default 0.5 (e.g., if this constant is set to 1.2, then 0.7u of insulin will be delivered immediately after the cannula insertion which uses 0.5u of insulin to deploy).

[yeagerm]

I recounted my own experiences dealing with this problem that has helped considerably:

https://loop.zulipchat.com/#narrow/stream/144615-omnipod_users/topic/Slower.20insulin.20absorption.3F/near/166178297

It's not foolproof- I still have noticeable "underdelivery" about 20% of the time and sugar surf a bit until normalizing. I agree that your proposed workaround is a better solution.