Air bubbles

Is anyone encountering air bubbles in their Medtronic quick set MMT-397. I have a 630G and have encountered problems with air bubbles.

I think the #1 tip is not to use insulin straight out of the fridge. Let it come to room temperature before filling. have the pump standing on the short end (tubing connection up) when priming, and give it a couple of good whacks to get any air in the reservoir up to the top, so you can prime past them easier.

If you use the magnifying glass icon (upper right) and search for “air bubbles” or “bubbles in the tubing” you’ll find lots of old topics on the subject.


Thanks for your reply. We have been doing everything Medtronics ask us to do. I suspect problem is with these quick sets. They need further testing.

I ran quick sets for 11 years until a month ago, and never had bubble issues that didn’t start in the reservoir. I have recently seen here people discussing bubble issues with the Quick Set Luer Lock, but I never used that. Are you on a luer lock?

We are using the Medtronic reservoir paradigm - mt332a

One of the things I really hated about the old R/NPH days was trying to thwack the bubbles out of the syringe so as to get an accurate dose amount. One of the things I loved about switching to Lantus/Novolog MDI was: pens! thwack no more! And then there was the moment in pump training when the Medtronic rep demonstrated… bubble thwacking! Noooooos! And then, as if to punish me for daring ever to think bubble thwacking was gone from my life, the T1 Gods declared that my first batch of reservoirs, covering like my first six weeks on the pump, would be defective, which was only brought to light after I’d been struggling with bad numbers far past the point when I’d expected to be back in regular control or better. Because voids in the tubing! No matter how much I thwacked! Finally though, my penance had been served and the curse was more or less lifted by a recall notice in the mail and a fresh set of reservoirs. And yet, still must we thwack.

@MarieB’s tip about letting the vial get to room temp is what my trainer taught me, too, back when. It’s funny because I’ve run across comments here on TUD from experienced pumpers who say they’ve never heard of it and don’t do it. But it does help. Also you can check for voids in the tubing by eye–I think there are even some videos out there showing how to do it and what to do about it. It’s a more common failure point than the sets themselves. They can fail too but it’s usually pretty obvious and the causes are usually things like hitting a blood vessel, getting a partial yank-out that bends the canula etc.

1 Like

Also too: Welcome to TUD @michi! It’s a great community and there are lots of experienced patients and parents here who can help with just about any question you have!

1 Like

I run quickset on a Medtronic 620G and I am not having any issue. I do find I need to run more U in the tube prime to get insulin to appear at the end of the line before insertion. I used to run 5U in the paradigm and now I seem to push 7U.

1 Like