Bubbles 640g Humalog

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jusme

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Hello please can you help as I am having great trouble with bubbles forming in the reservoir of my 640g. I use Humalog and have never had the problem before but I have found over the last few days that bubbles are forming in the reservoir for no particular reason and of course they are stopping me getting my basal insulin and my BGs are rocketing and I have resorted to having an injection to bring my BGs down. I change the reservoir and Mini Med Quick Set and after 12 to 18 hours it starts all over again. I contacted Medtronics yesterday but because I had just changed everything again they said to call before I changed it - I tried today but after being transferred to America I got fed up of waiting after 15 mins and signed off.

Any ideas please?

jusme
 
Hi sorry I can't help, but wanted to give your post a bump up.
I hope you can get it sorted out soon.
 
Maybe the Humalog is off: have you got another vial you can try? Also do you keep the one you're using at room temperature? I've always been told that filling the pump straight from the fridge causes bubbles.
 
How do you get on expelling the bubbles when you fill the reservoirs and do you ensure you can actually see a bubble of insulin right out of the top of its neck, before attaching the tubing?
 
Hold the end of the cannula in the air higher than the pump, I never have had bubbles, bottles straight out of fridge ? Good luck jusme 🙂
 
Thank you for your replies.

Radders I keep the insulin I am using in a cupboard, the others are stored in the fridge until I need one.

Jenny you can see the bubbles when you are filling the reservoir and the large bubble that always occurs is pushed back into the vial, when the vial is removed I always tap the reservoir and push a small amount out to get rid of others that are in the neck and then I fit the cannula this is where I have been going wrong.

Hobie thanks I will try that.

Late yesterday when I had to change everything again I followed the instructions in book and it was a slightly different method to how I had been shown when I was put on the pump and so far no bubbles have appeared and I am keeping my fingers crossed. It seems so strange that after 13 months of filling it as I was shown that the problem appeared.

jusme
 
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Hope you have cracked it now @jusme! 🙂 So frustrating when the technology starts playing up for no apparent reason!
 
Well that last bit's exactly what I used to do with the Combo - leave to plunger in situ in the bottom of the res and attach the tubing and give it another shove, before removing it and loading the res into the pump - all upright, then priming. Because of the few units already in the tube, the insulin would drip freely out of the other end by the time it reached the end of the amount I'd set for the prime.

Do you want to share the difference for those of us without access to the 640g instruction book - cos my friend with a Combo using Apidra has always had shedloads of bubbles and occlusions and I've never been able to understand why she does yet I hardly ever did - but there again I've never seen her filling a reservoir or inspected her insulin vial before she did it.
 
Yes please from me too. It would be good to know what the magic trick was.
 
Jennie & SB2015 if you take a look at Filling Your Reservoir Medtronic Diabetes (Settings and Features for C512/712) it gives you the instructions that I followed the other evening. It is number 10 that I have not done before.

It sounds just like you described Jenny.

jusme
 
Hope your new method is working OK for you @jusme

I had all sorts of issues with bubbles in the tubing in my first year and eventually ended up with this method: https://www.t1resources.uk/resources/item/medtronic-minimed-640g-set-change/

I still get occasional small bubbles appearing during use as the insulin warms up next to body temperature, even though insulin is at room temp when I fill. My other strategy is to hang the pump such that the tubing is towards the bottom when in use. That way if there *are* any pesky little ones in the reservior they float harmlessly upwards away from the the business end.

Out of interest - how do you get on with Humalog in the pump? My clinic do not allow it for use in pumps as it used to have a bit of a reputation for crystallising in pump tubing.
 
Thanks Mike that was very interesting and I will try out your tips when I do a change tomorrow. When I was given my pump as I was already using Humalog I was kept on it but I did notice everyone else was using Novorapid, I haven't noticed any crystallising in the tubing as yet.

jusme
 
jusme said:
When I was given my pump as I was already using Humalog I was kept on it but I did notice everyone else was using Novorapid, I haven't noticed any crystallising in the tubing as yet.

jusme
Click to expand...

So was I! And they swapped me back to NR when I started. Good to hear it hasn't caused you any problems.

Fingers-crossed for a bubble-free future 🙂
 
jusme said:
Jennie & SB2015 if you take a look at Filling Your Reservoir Medtronic Diabetes (Settings and Features for C512/712) it gives you the instructions that I followed the other evening. It is number 10 that I have not done before.

It sounds just like you described Jenny.

jusme
Click to expand...

It is what I said LOL - but I wasn't actually shown to do that, however it is the equivalent to doing an airshot with a pen to me, so I simply considered it was sensible to make absolutely certain no air from the new tubing decided to percolate into the reservoir. My DSN actually said to remove the plunger and tap the bottom of the res on a flat surface before attaching the tubing - but the snag with that is if there IS any air in the res, then you have to reattach the flipping plunger again, what an unnecessary palaver LOL
 
Bubbles appearing in the reservoir during use are due to any temperature difference between filing and use. Unlike solids, gases become less soluble as the temperature rises, so if you filled the reservoir at room temperature (maybe a bit colder than usual at this time of the year) and then kept the pump in your pocket at a nice warm temperature you will find that some air that was dissolved in the insulin will start to form little bubbles. Personally I don't worry too much about them as they tend to take a few days to form and it's then time to change the reservoir.

BTW how did you see them in the reservoir with the 640G? Mine is totally enclosed when in place.

You might try keeping the insulin vial in your pocket for an hour or so before filling the reservoir. That way there should not be too much of a temperature change.
 
m1dnc said:
BTW how did you see them in the reservoir with the 640G? Mine is totally enclosed when in place.
Click to expand...

Only observing that the reservoir is bubble-free when I fill it, but there are often one or two small ones lurking near the plunger end when I do the next set change.

They never seem to cause me any problems (at least not that I have identified) so I have not bothered about warming ht einsulin to nearer body-temperature before filling each time.
 
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