Not something I worry about. Been using pump for 30+ years. Carry a U100 syringe whenever out of house. With normal syringe, I can withdraw insulin from pump cartridge, in case of pump issue, and do manual injections. But have never needed to do so.
Or could carry insulin pen for backup, which I have never used.
Some folks do partial daily injection of long action, then pump lowered basal from pump. This may work well for active sports, when pump is removed during sport.
I just take the glucose, and maybe a couple extra. In theory the food should slow down the glucose, but somehow it seems I can still get out of trouble by chewing some glucose tabs and rinsing it down with water. If it felt like the glucose wasn’t enough, I would microdose some glucagon. I have several of those glucagon rescue kits, and supposedly they still work after expiration. So maybe I’d mix one up and take 10u or 15u (rather than the full amount) to provoke my liver to release some glucose. I think one of the new glucagons (was it Gvoke?) is available in a vial, which would also be suitable for microdosing.
I used to fill the t:slim cartridge completely full and run it 5 to 6 days until it ran out. (I treated the cartridge with an infusion set tube as a single unit, but I changed the infusion itself set every three days and saved the tube from the new set.) The extended duration still worked fine for me. I have seen postings from others who felt that the insulin wasn’t working as well after being in the cartridge a few days, but I don’t think that’s a widespread experience. You could always run the experiment yourself: pre-fill a cartridge a few days before starting it, and see whether the insulin seems to be working normally for you. Anyway, I wouldn’t pre-fill multiple cartridges. I’d prepare one, and use it up at the next cartridge change.
But I have to say, I wouldn’t use that approach for myself, because I don’t understand the 20-30 minute cartridge change. For me, I would guess it takes about 5 minutes, so I’m wondering if you just haven’t yet learned how to do it efficiently. These are my steps: Suck air out of the cartridge using the syringe, fill the syringe, remove bubbles, flush remaining air from the cartridge, remove bubbles, fill the cartridge. Attach the new tube to the cartridge, put the cartridge in the pump, and have the pump fill the tube. Connect the tube to the existing infusion set. That really shouldn’t take anywhere near 20 minutes, so that’s something to explore to reduce your burden on the t:slim.
Wait a minute. I just reread what you said. I don’t understand how a cartridge can fail in the middle of the night. If an infusion set fails, just insert a new set, remove it’s tube, connect the existing tube from the existing cartridge, fill cannula. Two minutes?
@bkh Wow! That is all good info. You are right - I never thought of using a new set and reusing the tube! Geez! And yes, I have been wathcing youtube videos to learn how to be precise when changing the whole thing and it does take me 15-20 minutes, but I will improve over time. Just so much more than OP5 that I have now made a mountain of a molehill because I used t-slim first and then got accustomed to OP5. Thanks for all those pertinent points, especially about my brainfart about i fusion set pulling out in middle of the night.
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