Disscussion: Looping < 5 Min = Frequent CGM Updates

[Tornado-Tim]

Hello All,

Just raising a discussion in regards to a post on Facebook about the Libre 2 and its possible 1 min delta updates.

Medtronic Pumps are fairly slow to Loop from (well to loop from safely anyway) in comparison to Modern Loopable Pumps (Dana R/RS), with the possibility of CGM delta Updates being less than 5 min in future CGM devices, its worth discussing changing how to approach this.....

As it currently stands: OpenAPS (oref0/1) will Loop on every CGM Update, Since Loop times on a Edison OpenAPS rig are around 2-3 min, this poses a question of the system will always be in the middle of a loop (ie: no-rest period). On AAPS oref0/1 will loop in under 15 seconds with a DanaRS.

SMB's will only be enacted every 5 min (so this would not change under the above), but should the 5 min rule be changed? Current SMB Status: Currently delta changes used for SMB are in every 5 min delta update, but we have the option for even more safety here, while achieving sub 5 min SMB's in a rather safe manner:

Proposal for a safe sub-5 min SMB dosage So if CGM updates were coming in on the min, we could ensure delta updates were "Smoothed" based on on the sub 5 min delta updates by taking a sample of the 3 most recent delta updates getting the avg delta increase and dosing a SMB on that value. This avg delta increase can be added to the 15 min delta weight to even add more safety and less likey overdosage, yet kick more quickly for those unexpected UAM's or carb heavy meals.

Anyway just opening up the discussion on this, should OpenAPS loop on every update?

In some situations where the Pump can do it, I would say yes, but for Medtronic and OpenAPS rigs, this would need limiting to a setting say "Max_Loop_cycles_per_5_min", but keen to get others ideas on this.....