Does anyone know if Tandem makes clear cartridges like Medtronic does? Getting the air bubbles out is maddening with these black cartridges! Especially frustrating because I’m really insulin sensitive and don’t need much for my TDD (~25 units will serve me). I already waste a ton of insulin because Humalog is only good for 2 days in the t;slim and minimum fill is 50 units. Tired of wasting another 20+ trying to get the bubbles out!
Thanks for letting me vent, btw. Insights on whether an existing alternative is out there or how we can petition for one is appreciated.
I switched from Tandem to Omnipod a while ago and don’t know about current cartridge options. I can only suggest you try to eliminate as many bubbles as you can when filling the syringe. One thing that helped me was making sure the needle was tightly connected to the syringe before drawing up insulin - it may sound obvious, but I remember calling my doctor’s office about excessive air bubbles when I first started on Tandem, and getting that suggestion. Likewise make sure the tubing lock connector is securely screwed in place.
Here’s something from Tandem that may help:
I wasn’t aware Humalog only lasted 2 days in a Tandem pump - is that new? Years ago I used to use it for 5-7 days in mine (although now I know 3 days is the maximum recommended), and three in my Omnipod. If it does in fact last longer, since your daily needs are low you might look at drawing out the remaining insulin to use in a new cartridge when you change your site after two days.
As far as I know, tandem does not sell clear cartridges. Would be nice if they did! I’ve been using the tandem for 3 years and for most of that time I’ve been filling my cartridge to the max, 300u, and only changing it when it’s empty. That means that the insulin is in the cartridge for about 7 days. The only times I’ve had issues with the insulin degrading are when exposed to extreme temperatures (upwards of 90 degrees) for several days. I solved that issue by changing my cartridge out every 3 days as suggested by tandem and using a frio pack. Another time I had a ton of bubbles in my tubing after we’d been skiing for a day. I pumped about 30-40u of air out of my pump that day. I think that was due to altitude but I don’t know. It’s never happened again.
The Cartridge load process can be a bit tricky, there are lots of little steps. You could go watch the “how to load a cartridge” video on tandem’s YouTube channel just to make sure that you aren’t accidentally skipping a step- sometimes those videos are helpful to review again.
Some other tips:
- like @wadawabbit suggested, make sure that the needle is tightly screwed on and that you’ve pushed all of the bubbles out of the syringe.
- don’t shake your insulin vial before you pull the insulin out.
- when filling the tubing, hold the pump straight up vertically so that the tubing sticks out of the top. This can help pump air bubbles out first because they’re supposed to float to the top.
- REMEMBER to pull the air out of the cartridge before filling it with insulin!!! Sometimes I forget this step and it always results in a bunch of bubbles in my tubing.
Good luck trouble shooting!
Another suggestion to add - let your insulin get to room temp before filling. Back in the day (cough cough 30 or so years ago) I kept mine in the fridge until I was ready to load a cartridge. Now insulin is good at room temp for 30 days once opened, and that alone prevents a lot of bubbles from forming.
@Htanona Welcome Helen to the JDRF TypeOneNation Community Forum!
The only cartridge for the t-Slim x2 is the one you are currently using; two weeks from today I will be using the t-Slim for five years and I haven’t had any issues with air bubbles in my insulin. Yes, at first I found the cartridge-fill process a little slower than the Medtronic but after a month or so it became routine. As far as air bubbles in insulin, NEVER use cold/refrigerated insulin for a pump or an injection - unless you are using insulin taken from a live animal and, when injecting air into a vial before extracting insulin make certain that the vial us facing upright - this method [in both Medtronic & Tandem instructions] prevents us from “bubbling” the insulin.
Insulin in a Cartridge or Reservoir is okay to use for seven days, not two days - printed on the flyer packaged with the insulin vial. In recent years for my moderate carbohydrate healthy daily food intake [230 to 250 grams of carb], I average 19 - 21 units of insulin per day and never waste any insulin in the cartridge and total tubeing-fill and priming totals less than 15 units even when using a longer tube length. There isn’t any law or rule that states a cartridge MUST be changed every time an infusion set is swapped out.
Thanks all for pushing me to try to find the Tandem site page where I learned that Humalog was only approved for 48 hrs in the T:Slim cartridge. Long story short, I can’t find it, though there are breadcrumbs scattered in the Tandem documentation and posters in other forums complaining about the same information as received from their doctors. My search on the FDA. gov site turned up some evidence that 48 hrs was the approved duration in 2005 (https://www.accessdata.fda.gov/drugsatfda_docs/label/2005/020563s054lbl.pdf) but I also found documentation from Eli Lilly that the FDA changed that direction in 2011 (https://investor.lilly.com/static-files/32cb1a6d-7642-4928-9804-2ec05070a5ab). My guess is that the Tandem site wasn’t updated timely since I found that page sometime in 2022 after fighting some persistent highs that led me to believe my Humalog must be crystalizing in the cartridge (I was, as Lise suggested, filling the cartridge full and then filling the tubing of new infusion sets so that I could change the sites every two days).
Anyway, thanks for making me question my source and dig around some more.
Helen @Htanona, rather than refilling the tubing every time you put in a new infusion set, disconnect the tubing at the old set and attach the already filled tubing to the new device - and only use prime cannula for the new.
I rather throw out an unused tue than waste 10+ units of insulin.