Blocked Infusion Set

My son, Dylan, is 4 years old. He started pumping on February 13, 2010. He uses the Animas Inset 90 6 mm. His infusion sets are lasting 48 hours at the most. On Sunday, only 1 day into that infusion set, he spiked to 440 with moderated ketones. So, we switched out the infusion set and everything went back to normal. Today is Tuesday and he spiked again around 2 am. He was 264 and I gave him a correction. By 7 am, he was 289 with small ketones. I assumed the infusion set had gone bad again (only about 36 hours into this one). When I removed the old infusion site, I could see that the cannula was clogged with insulin crystals. I've been pumping for 8 or 9 years and have never seen this on myself.

Does anyone know why this would happen? Is this insulin bad? Should I consider changing infusion sets for him?

I’m not sure Roxanne - I would call Animas and ask them for advice as well but I would also call your son’s Endo.

My son is also 4-years-old and we use the Inset 30’s (angled instead of straight). He’s been pumping since July 2009 (when he was 3). We’ve found that the sets last longer when put into deep enough fatty tissue and MUCH shorter if too near muscle or an area that has a lot of skin movement… because of this Tyler can only take sets on his butt right now and only in the fattier parts… we try to avoid putting it directly on the area where he sits and we also try to avoid getting too near the edge… that leaves about 3-4 square inches on each cheek that we can carefully cycle through and rotate.

As he grows I know we’ll have more areas we can use - but for now that’s it.

We typically and regularly get 3 full days (72 hours) out of a set with Ty… and he’s a rough and tumble boy all the way. Sometimes only 2 days… but that’s rare.

I’ve never experienced the “crystalizing” that you speak-of… we use only Novolog as that’s what our insurance covers but we have used Humalog in the beginning and that seemed fine as well.

I don’t protect it at all. It’s hooked on his waistband or in his pocket. When I do a site change I blow all the dust off of it :slight_smile: We have not had any crystalizing, but nobody told us to keep it extra clean or in a baggy either. I read that there’s a “breathe hole”, the dot next to the cartridge cap that you need to make sure stays clean. That’s the spot I blow on to make sure there’s no dirt in there. We go 3 days between changes and could probably go longer most of the time. The few times we’ve had to change sooner were on the skinniest parts of his belly. There’s not a lot of room there with enough fat, we also use the top of his buns when he’s running high due to a little more fat there.

Good Question!

We live in Colorado and have been pumping since July so we have seen a couple hot days and have definitely seen some cold days. For most of the hot summer though we were still on MDI (shots) so I haven’t been through a full summer with him yet.

In the winter it’s been “ok” because his pump sits in a homemade thick fabric pouch right next to his skin… I feel like this keeps it just warm enough without being too warm. We’ve never put it in a ziplock bag. I wonder if you’re having excessive moisture problems in MD inside the bag? It’s very dry here in CO so I couldn’t say.

In the summer so far (last year) - since pumping - we’ve just been watching his numbers after a hot day/event outside. I think once or twice we have had to do a set change after a particularly hot day but for the most part he’s been ok. Maybe we’ve just been very lucky.

Hi Roxanne,

My son Matthew (5) began pumping in Nov '08. Our first six months went very well, sets lasting 72 hours, A1C’s of 6.1 and 6.1. During the second six months we couldn’t get a set to last longer then 48 hours, and when we tried, we’d experience the random highs you’re having. A1C’s reflected this and were 6.5 and 6.3. We thought it may be the summer heat, but it didn’t get any better as we rolled into winter. In the last few months it had gotten very bad and we experienced many spikes and early set changes, often less then a day. It was frustrating and his last A1C a few weeks ago was 6.7, his worst on the pump (his standard deviation had really gone up too, that telltale sign of poor control, even with a decent A1C).

In the past few months we’ve tried changing insulin, different infusion sets, different sites, and even exchanged our pump (MM Paradigm).

In the end, we ended up where we started: MM Paradigm, Quickset 90’s, 6mm (similar to what you are using) and Novolog, but he has been doing much better recently. Indeed, we’re back to 72 hours per set, with only occasional early changes required. I attribute this to two things.

  1. We are now using his stomach and not just the butt as we had been, providing more site availability. I think that after only having used that area for over a year he may have developed some scar tissue, inhibiting absorption, although it has gotten much better with less use.

  2. We elevated his basal rates slightly so there is a higher flow of insulin. I think the higher rates may prevent some clogging/crystallization. Of course, that is an option for the daytime, but obviously there’s not much you can do at night. The difference in basal rates may be why you’ve never experienced this, but your son has.

Additionally, the number of times we test per day has gone up compared to when we first started on the pump as a result of trying to head off the random highs. This has had no effect in avoiding early set changes, but has provided indication of pending failures and kept some numbers lower then they might have been.

There were several days we considered putting Matthew back on MDI. It was difficult seeing the 400’s pop up and knowing we had more consistency and better control with shots. I’d keep experimenting until you find a combination that works for your son, keeping in mind that it may be awhile. Matthew loves his pump. For us, it’s been worth the effort.

Wow - very enlightening info from Dean for me as well since my son has only been pumping for about 6-7 months now. Things are still going “well” for us but we certainly have our days.

Just for a point of reference, Ty’s latest A1C was 7.4 (still down from previous scores)… his Endo is happy with it… I’m not so sure.

Also for a point of reference, Ty’s basal rate runs around 1.250 (varies depending on time of day) but it never goes below 1… so that’s a big difference in flow rate - attributing to Dean’s idea.


I forgot to mention one more change we have incorporated (or tried to) in Matthews pumping. In the past, I would load his reservoirs for three days of insulin when we did a set change (60-70 units) to cover priming, use, and a little spare. I found that Matthews set failures always occurred when the pump was less then 45 units remaining. Maybe coincidental, but an observation nonetheless. Recently, I started loading him for six days (Novolog approved reservoir duration) plus 50 units “spare” with the intention of changing the reservoir at 50 units - a lot to throw away, but insignificant when you consider what we tossed during the multiple early set failures. Along with the previously mentioned changes, it seems to be working. And yes, that means I carry over a reservoir and “old” line to a new set.

Here’s a bit of anecdotal evidence. This morning he woke at 110 with 39 units remaining (I was supposed to change the reservoir last night). In a hurry to get to kindergarten, I sent him off without changing it. Results, 193 at snack time (highest in three weeks) and home for lunch at 214. Changed out the reservoir, and he’s back down this afternoon. This has happened to many times for us to ignore and I’ll do better changing it out at 50 units.

I would guess that you don’t load your son’s reservoirs with too much insulin due to his low use/low basal rate and presumably high sensitivity (?). Just something else to consider :slight_smile:

Matthew’s basals range from .20 to .50. During his honeymoon phase on MDI his Lantus use was between 0 and 1 unit (there were times we coudn’t give him any because he would go hypo overnight with only .5 units - we used the BD needle with the half unit marks to get him there). Today, Matthew’s total basal is 7.50 units/day which translates to the low rates, so his basal has increased over time. Looking at Ty’s rates above I’m amazed at how different two children around the same age can be! Again, I assume that is reflected in each childs sensitivity. As a point of reference, Matthew is set at 250, determined after many hypos post correction (no carb).

His “sensitivity factor” used to calculate his correction insulin when BG is off target (or how much one unit of insulin will lower his BG). Actually, his drops to 220 during the day (0600-2100). These are the numbers I have programmed, or “set” in his Paradigm.

I say Matthew’s sensitivity is high as a 220-250 range would be indicative of somebody using 7-8 units total daily insulin (where he uses 15-16 units).

So, Dylan’s sensitivity is “normal” and your endo’s assumption that his low basal rates may be due to his honeymoon phase sounds right. Whereas Matthew’s endo isn’t sure why his rates, sensitivity, etc. are what they are, only that they work.

In any case, I hope you work out the infusion set issues. I know how frustrating it is to see the unexpected 300+, having your child deal with that and a set change after one day of use.

this-from what i read-sounds like a great idea…i just want to make sure that i’m following you to a ‘T’ !
my son, ben is 3 yrs. old and is on an animas 2020 and uses the contact detach infusion sets. weve been pumping for 1 1/2 years.
his ‘sites’ usually last about 3 days…considering he doesn’t take 2 baths a day…because he HAS to play with his shark toy or get yanked out for being a rough n’ tough lil’ guy.
when i fill his insulin cartridge, i fill to about 55-70 units and after priming the tubing, i’m left with about 40-60 units.
when i change his site every 72 hours, i change the cartiridge, tubing, etc, the whole shabang…usually we have under 10 units of insulin left in the pump.

so with what you are saying…i hope i follow…
fill up for 6 days vs. 3, and when i change his site every 72 hours, don’t toss the remaining insulin until the NEXT change…and just change the tubing/insertion set???


We’ll load up a reservoir (cartridge) for six days during a set change. Three days later, we insert a new infusion set, disconnect the new tubing, and reconnect the pump with the reservoir and old tubing, and just fix prime to fill the canula (so you don’t have to prime out new tubing). I do inspect the old tubing to ensure it has no damage as it’s been worn for three days, but I’ve never replaced one because of that. Also, we’ve kept a few of the new tubes in a zip lock bag just in case, but again, we’ve never used one. If everything goes well, you’ll use half as many reservoirs as infusion sets (and have a lot of left over tubing).

Keep in mind, Matthew uses a MM Paradigm, and that this is a technique I use, but I’m sure Animas would not recommend it.

i couldn’t imagine paradigm would recommend it, either…right!!!
thank you so much…i am going to try this. many times, if bens site gets yanked out, i will just change out the canula…no reason to do an entire site change with new insulin for a little malfunction!

i will update you and let you know how it goes. thanks again…and best of luck to you and matthew!

wow! that is good to know, i will ask our educator and see what she thinks.
i am going to do a trial run of it first and if it turns out successful, we’ll continue, if not-it was worth a shot!

thanks again.

I get between 10-30 hours out of my 4 year olds set. He always gets an occlusion alarm under 10 units of insulin left. I change the cartridge with 20 units left in it. We have had two days in a row with a 12 hour set and a 10 hour set. I am about to put in the 3rd set in 1.5 days.

I feel like giving up. There is no fat to use. He is skinny. The bum is used up.

I think I will try the Inset I which are the 30s. I am using the 90s right now. Arghh! I know how you guys feel.

We tried Orbit Micro steel, Accu check rapid D steel, cleos teflon, and now we are on INset II 90 degree teflon.

Changed the site this morning when Payton hit another “18” high. The leg site lasted only 10 hours, not even.