How many days do you wear an infusion set with steel cannula?

I’ve read somewhere that two days are max, but can’t find this info when I search. Is this true or just something I’ve made up?

And have you worn yours for more than two days without trouble?

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I can't speak for all the different makers of steel cannula but in the instructions for the ACCU-Chek Rapid-D steel cannula it has the following under "Steps to Avoid Infection"

• Rotate the sites as recommended by your healthcare
professional or every 24–48 hours.

The link to the pdf is as follows:

I am sure other companies will have similar documentation available so for the brand you are using I would go and look for the info on their web site just to be certain but from what I have seen it seems to be the same for most steel sets.

I myself don't use the steel ones but with the Teflon ones, I know they recommend 3 days and when I have tried to go a 4th day, I have seen a rise in blood sugars which I have put down to poor absorption around the cannula. Someone else maybe able to give you more info having tested the steel ones beyond 2 days but I thought I would pass on what I think most of the companies will say and it isn't just something you have made up.

Thanks, thewall. I had forgot that I could check the instruction leaflet that comes with the cannulas, which - off course - I never have read

"Change the infusion set after maximum 12 hours use...."I

I think I just stick with 48 hours like I do today.

The sets I use is is Neria detach from Unomedical. The pharmacy refers to them as Contact detach.

I’ve gone three, three and a half… occasionally reached four… with no real problems. I’ve also removed and reinserted those sets when I suspected something may be wrong with the site. Does that count as restarting the clock? I’m not quite sure.

The steel cannula is much thinner than the teflon one, so I find it lasts more comfortably, longer. (That, and the two-sticker design means you never encounter tugging on the site)

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I get almost two whole extra days from the steel ones (contact detach is my favorite) than I do from the teflon ones, although like thewall points out, the directions actually say to change more often. I get at least three days and usually 4 is okay, but I'm generally out of insulin by the end of 4 days and I think its easier to just swap it all out at once even I could maybe get another day out of the site. My results with the teflon sets were pretty poor, and I was changing those at least every other day, and sometimes every 24-36 hours. Getting 72-96 hours out of my sites makes me a lot happier!

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i wear mine always for 4 days with no problem. The problem I have is finding enough new places to put it? Any suggestions? Can't use my stomach anymore cause I have scar tissue there after 4 years.

Hi Siri & others, I’m persuaded to try the steel cannulas and before I order them I’m trying to find out why the general recommendation is to change them every 1-2 days compared with every 2-3 days with the teflon sets. So your post here is nicely relevant!

I started pumping nearly 2 years’ ago & stretched my teflon cannula changes to 4-5 days, occasionally 6. Then I gradually learned about the risk of infection (which personally I wasn’t gonna worry about & don’t feel I’m particularly at risk) and scar tissue formation. So I got into changing every 3 days and occasionally 4 days.

Scar tissue BAD news for future reuse of sites!!

My question of why do you need to change steel more frequently than teflon has resulted in someone on a UK list saying cos of scar tissue forming more easily. It’s really difficult to find out (books, googling, lists…) WHY! If the steel ones cause scar tissue to form more easily or more quickly than the teflons, then why is that? I know there’s some nickel in the steel cannulas and that could be a problem if you’re allergic to nickel, but otherwise steel seems pretty well tolerated.

What do you guys who stretch the limits on the steel think about scar tissue formation if you don’t change every 24-48 hours?? I really don’t want to change my cannulas that often! It’s putting me off trying them.

Siri - how have you got on with them?

Hi Siri, I have worn the sure-t infusion with steelcannula for nearly a year now & change every 4 days. Never got an infection yet nor scar tissue. I had to do this because after 3 yrs of the teflon cannula in my stomach area I did get scar tissue, bg's were high & my diabetes educator informed me that I couldn't use my stomach any more. Advised me to use my sides. I don't have a lot of fat there,& hard to find new places to go. Good luck if you decide to try the steel ones.

Thanks, that’s very useful to know.

After much more googling, have now found this very recent paper :

which includes this little gem

“Length of use recommendations for IIS is generally 2 days for steel sets and 3 days for Teflon sets, although we are unable to find any data supporting these recommendations and at least one study found no difference.”

So, it seems there’s no evidence-based reason for the 2 day recommendation for steel vs 3 days for teflon, and in the end it’s what suits you (& maybe your pocket unfortunately) &/or the risks you’re prepared to take. Although I stretch some things to the limit, I would be concerned about inadvertently causing too much scar tissue by leaving sets in for too long, too frequently, and it may be deep or cumulative scarring build up, so not be apparent for a long time.

Betts - just wondering what your D educator thinks about the 4 day change period? Are they ok with that?

Yes, she knows & is ok with that.

I still stick with every second day, Ingřid Glass. I change the reservoir at the same time as the cannula because Eli Lilly says they can´t garantuee the effect of Humalog in a plastic container for more than 48 hours. I still like the steel cannulas and they work almost 100% of the time and that´s a relief.

Hi Siri, Oh how interesting! Animas say 3 days for cartridge change, Roche say up to 6, but Eli Lilly say 2 days… I just wish they would be consistent with each other!! So confusing. I often use my cartridges for 6-7 days, and even up to 10 days yikes, and then refill (I know this is not approved of…) and have never observed loss of potency. As I change cartridge and cannula separately, I can tell easily if BGs go up or down what the cause is, and it’s never been the insulin/new cartridge, only failed cannula or bad (or extra absorbent I had recently!) site. I’m not recommending anything to anyone else, it’s important to feel safe and comfortable with what you do (I remain cynical about pharmaceutical/medical co.s’ recommendations however, as it’s in their financial interest to encourage frequent use or change of consumables, but I accept it’s up to the individual (& their purse or insurance co. or NHS in my case) in the end).

Well…I have my steel cannulas now but as I’m away from home I feel safer waiting til I’m back to try them out. Quite excited by it!

Hi Ingřid Glass, I found this about Novolog:

"Reservoirs and infusion sets:
NovoLog is recommended for use in any reservoir and infusion sets that are compatible with insulin and the specific pump. In-vitro studies have shown that pump malfunction, loss of cresol, and insulin degradation, may occur when NovoLog is maintained in a pump system for more than 48 hours. Reservoirs and infusion sets should be changed at least every 48 hours."

It´s from here,- it´s written by the NDA.

I know I found something about Humalog too, but I can´t find it right now. It´s not the pump manufacturers but the insulin producers that have a say about how long they can garantuee the insulin to work a 100% when taken out of the original glass container and put in a plastic cartridge. It was my pump rep. that originally told me that 48 hours was max for my Humalog.

I change my set every 3 days, reservoir about every 6 days.
i have never noticed any changes in insulin efficiency over the days. of course that can be different with everyone, if you want to go sure, change it every 48 hrs, but i personally have had no problems using it way over that limit.

Hmmmm this is from Eli Lilly for Humalog :

“To avoid insulin degradation, infusion set occlusion, and loss of the preservative (metacresol), insulin in the reservoir should be replaced at least every 7 days; infusion sets and infusion set insertion sites should be changed at least every 3 days.”

from (section 17.2 on pump use)

I’m sure the different insulins need different recommendations and some degrade or crystallise more quickly once decanted into plastic reservoirs, but there is still inconsistency in advice given within that it seems! In the end, do what feels safe and works for you I think!

And this says up to 6 days in reservoir for Novolog

Oh, inconsistency reigns supreme! I think I’ll stop googling now!!

Happy set changes everyone whichever insulin you use and however frequently you change…

Hi, Ingřid Glass. I´m just curious,- have you started with the steel cannulas yet? And if so, how is it working out?

Hi Siri, used a few now (wasn’t convenient until after Easter to start something new) and I’m liking them - no pinching during yoga which I was concerned about. I like the ease of insertion with no worries about cannula failure/bending with manual insertion.

But…Roche sets don’t really fit the Vibe, there are extra plastic ‘wings’ above the luer lock coupling which I have to force thru the end cap before screwing it in place securing the cartridge in. Doesn’t seem right to me. So I got some steel sets from Animas & several things about them annoy me, not least that I’m comfortable with ~30" tubing which they don’t do!! Only 23 or 43. And I forgot how I’d got used to the clearer to see Roche tubing…back to Animas “is that or isn’t that an air bubble?” markings. Other things too like the Animas click clips for disconnection of tubing…much much prefer Roche. I’m currently trying to get hold of Orbit Micros to try, having seen them mentioned here, but not sure they’re available in UK.

I’m leaving the steel cannulas in for 3 days which seems ok so far, in fact I’ve had fewer & shallower post-set removal ‘lumps’ compared with teflon.

Glad you like them so far, Ingřid Glass. I have an Animas Vibe and to secure that it stays waterproof you need to use a tubing with luer lock only. Like this one

You can, like I do, use only the 6 (or 8) mm steel cannula from one infusion set and the tubing with a luer lock and the length you prefer from another infusion set. If you are able to money wise or insurance wise, of course.