Wednesday, 28 March 2012

Infusion set drama

I feel like my pumping life has consisted of a heck of a lot of infusion set drama. I'm on the Medtronic 522, and in this blog I am going to account what has put me off each infusion set, and why I'm now kind of stuck.


The Quick-Set was the first infusion set I used. I used 6mm Quick-Sets because I don't have much body fat. My foray into Quick-Sets was awful, short-lived and almost made me quit the pump entirely.

Through this period (several weeks) my BGs consistently ran over 20 (360), however much insulin I took. Occasionally I would put in a new set and come down to the 100s for a few hours, before dramatically shooting back to the 300s. When I removed the Quick-Set, it would inevitably be kinked. It was a horrible start to pumping for someone whose BGs only went over 300 occasionally whilst on MDI. My parents were even encouraging me to go back to MDI.

Luckily I continued with it, and moved to the next infusion set recommended by my CDE.


I used the shorter of the two Silhouette options - I think they are 13mm. They are an angled set, as opposed to the Quick-Sets which go in at an angle (both Quick-Sets and Silhouettes are made of teflon).

Silhouettes were what showed me that pumping really could work. My BGs were beautiful for the first week that I used them. However, on my third Silhouette my BGs ran higher and when I removed it I saw that it was kinked. I kept using the 3 month supply that I had, but found that between a quarter and a third of the Silhouettes I inserted would end up kinking.

The kinking of Silhouettes was not as bad as that of Quick-Sets. Because the Quick-Sets tended to kink at a 90 degree angle and block all insulin flow, I would rapidly end up over 300 or even 400, with ketones. The Silhouettes, on the other hand, would make my BGs run a little higher (in the 200s, usually), but there was clearly not a total blockage of insulin, just some kind of impediment in flow. However, I still felt that I could do better; having kinked infusion sets a lot of the time felt sub-optimal, even if the insulin delivery wasn't totally blocked. So I called my CDE and we decided that I would try out a new infusion set, that I had been wary about.


The Sure-T is a 90 degree infusion set (like the Quick-Set) but it has a steel needle which remains in the body, rather than a teflon cannula. A steel needle clearly will not kink in the same way that teflon is prone to, but I was wary of having a needle in me all the time. What if I bumped it on something and it poked me and really hurt, and surely it would leave a bigger bruise and more damage than my other infusion sets. Also, it just felt kind of creepier to have a piece of metal stuck in me than a piece of teflon. These worries about the Sure-T are not uncommon, I've seen a lot of people worried about it over at the CWD forums. But in the name of science, I decided to go there anyway because I didn't like the whole kinking thing.

Sure-Ts actually really aren't that bad. There are two 'stickers', one which sticks on the actual needle, and then another further up the tubing. This means that if you catch your tubing on a doorhandle, it doesn't pull the needle itself out (unless you tug really hard, which I actually did yesterday..) but only pulls on the sticker further up the tubing. That is a really good feature, because if you think it hurts to accidently rip a teflon cannula out of your skin, it HURTS to rip a steel needle out. Extra security is good.

It seems that I have used Sure-Ts for longer than 3 years of my diabetes timeline. For the vast majority (more than 3 years) of that, I had absolutely no problems. They removed a whole factor from my diabetes care. When I used teflon sets and I was troubleshooting a high BG, I always considered the fact that my set could be kinked, but steel sets never kink and for a large part of my Sure-T usage I didn't even have a blockage. I didn't have any set issues at all, which was amazing.

Sure-Ts are also really easy to insert, and wearing them is hardly ever painful. The insertion is just like doing an injection (no horrible insertion device). Having the needle in the skin is surprisingly painless, unless you hit a particularly sensitive area (my infusion site sometimes hurts a little for an hour or so after insertion, but that is not unbearable and it is very rare for the pain to go on longer). I'm not involved in contact sports or anything, but I am hugely clumsy and have hit my site with things more time than I can count, and it was never a problem.

Sadly, my love affair with Sure-Ts is over. In the past 6 months or so I have had serious problems with blockages (not in the main part of the tubing, but either in the needle or in the shorter part of the tubing, the 'tail' at the end). These occlusions end in 400+ BGs, no delivery alarms and ketones. I have been trying to ignore it but my overnight nausea filled ketosis on Monday night has meant that I'm really going to have to do something.

With my last shipment of Sure-Ts I ordered two boxes of Silhouettes so that I could try them out again.

Silhouettes, take 2

I weigh a bit more than I did last time I used the Silhouettes, around 135lbs rather than 115lbs (at 5ft 5). This means that I do have more of a layer of fat, and that probably helps (perhaps I should try the Quick-Set again!). I've gone through 20 Silhouettes and only had 1 kink. 1 in 20 is not a bad failure rate, and certainly better than I'm getting with Sure-Ts (especially because that was only a small kink, I didn't have any ketones or a markedly high BG).

In so many ways, I like the Silhouettes less than the Sure-Ts. They are less comfortable for me, insertion is more painful and sometimes the teflon causes itching. They also seem more prone to inflammation (perhaps minor infection, although nothing that I've needed antibiotics for).

However, I can't deal with any more of the Sure-T problems so I think for my next shipment (which I will order some time this week) I'm going to have to get Silhouettes.

In case anyone is interested, here is my ranking from best to worst on different factors:

Comfort: Quick-Set, Sure-T, Silhouette
Low failure rate (overall): Sure-T, Silhouette, Quick-Set
Low failure rate (right now): Silhouette, Sure-T (haven't used Quick-Set recently)
Ease of insertion: Sure-T, Quick-Set, Silhouette
Adhesive: Quick-Set (they stuck really well for some reason!), Sure-T, Silhouette
Attractivness: Quick-Set (adhesive rarely peeled up), Silhouette, Sure-T (I just don't like how they look)
Itchyness: Sure-T, Quick-Set, Silhouette

The funny thing about my rankings is that Quick-Sets actually win at quite a few things. They just had SUCH a poor failure rate that I can't imagine them working for me. Although I do still have a few lying around, so perhaps I should try again (I like going full circle).


  1. What kind of insulin do you use? I remember hearing that Humalog clogs infusion sets but Novolog was actually designed for use with pumps.

    1. I use Apidra - actually, my problems with Sure-Ts only started when I switched from Novolog to Apidra.

    2. Hmm. Any reason for the switch?

    3. Also, you might want to read this:
      and this:

      Seems like a lot of people have this issue with different types of pumps, infusion sets, and timing.

    4. I switched because for me Apidra has a DIA of 3 hours compared to Novolog's 5 hours, which makes it way better for dealing with meal spikes. However, it's worse for site failures. There's always a downside, right? But I do still have some Novolog in the fridge, so I could switch back until I've used up all the Sure-Ts I have left. Thanks for the links - I'll take a look!

  2. Have you tried Mio sets? They're sort of like the quick-sets but seemed to work better for me because each one has a new inserter. And they come in different colours :)
    Hope you find ones you like!

    1. I haven't tried Mios, mostly because I wouldn't like to throw out that much plastic with every set change, KWIM? Thanks for reminding me though, I will look into them if these problems don't resolve.