T-Slim or T-Flex and Occlusion Alert


@taytay1 have you checked for air bubbles in the tubing? T:slim is well-known for this.


You are correct about my antique real estate! However, it seems I do fine for awhile and then I get this rash of occlusions which I can’t figure out. Thanks much for brainstorming with me.


Oh wow! Zombie thread.


I switched to the Tandem T:Slim X2 recently. I have been experiencing a large number of occlusion alarms (2-3 per week) compared to my past experiences pumping over the course of the past 10+ years.


I have been using the X2 for about a month and have averaged 1 occlusion alarm per week. Whenever I get the alarm, I just press Resume Insulin or whatever the prompt is and I have no more problems. In 12+ years of pumping with Animas and Medtronic, I previously only had 3 or 4 occlusion alarms ever. So this really concerns me and lowers my trust in the pump.

At the same time I have to admit that I use the cartridges for more than 3 days. Each of the occlusion alarms has occurred when the cartridge had been in use for 7 or more days. I regularly used Animas and Medtronic reservoirs for 8 days with no problems. However, it looks as though I may need to limit Tandem cartridges to 6 or 7 days.


I normally don’t go up to that many days, but interestingly enough (because I have been lowering my carb intake), I have almost halved my daily insulin needs, so cartridges have been lasting longer… and now that I think of it, the past two occlusion alarms I have had were past the 3-day usage point.


I also made the big jump and went to Tandem a few years ago after being with Medtronic for 20+years. I use the t:slim not the t:flex but I also had occuslion alarms, which I almost never had with Medtronic. And after a lot of talking with the great people at Tandem and working with my pump trainer, I changed infusion sets. I went back to metal. I really don’t know why I waited so long. I think because when I first started pumping there was only metal and wow, they hurt. But I got a few samples, and discovered the new metal infusion sets don’t hurt. So I have been using metal for almost 6 months and have had no occuslion alarms. I really think most pump issues are not pump issues but infusion set issues. See if one of the infusion set companies can get you a few samples. Good luck!


I do not believe that my occlusion alerts are at all related to infusion sets. Not one of my occlusion alerts on happened with a set that caused any problems before or after the alert. I have used manually inserted Silhouettes/Comfort Shorts for my entire pumping career. I never got occlusion problems or even bad sites before Tandem and for me I don’t think that magically I am all of a sudden having site problems.

But of course I can’t say that your alerts were related to sets. I tried the metal sets a year or two ago and found them incredibly painful. It was like having a tack stuck in me. Plus the adhesive was horrible on the needle part and I had to use tape to keep it on. The anchor piece stuck great, just not the important piece with the actual cannula.

Good thing that we have choices. :grinning:


I have never done metal infusion sets. I don’t think I could get myself to go on them… :frowning:


My daughter had 5 yrs on the Ping with only 1 occlusion alarm. She’s been on the t:slim for just over 2 years. Occlusions were a regular occurrence for the first 3 months or so. Tandem’s advice was to try different infusion sets, which didn’t help at all. My personal belief is it’s the cartridge. We started tapping the cartridge before & during tubing fill & that helped. Since we’ve done the software update & can now fill the cartridge prior to attaching it the pump, we’re seeing regular occlusions again.


I have the t:slim and get semi-regular occlusion alarms. This happens most often if I’ve just programmed a bolus (especially a large one) and then return the pump to its resting place (usually in my waistband or a pocket). If I get the occlusion alarm, I clear it, reprogram the bolus, but keep the pump out until the bolus has been delivered before putting it back. That usually resolves the issue for me. So it seems I get the alarms if the tubing is coiled up or kinked.


I suspect the Tslim occlusion problem is in the micro-delivery or slow delivery of insulin. Tslim is one of the few pumps that delivers quite so gently and in such small doses. Slow delivery may be good for fresh, new sites or certain skin and tissue types, but not for mine. I seem to need faster, more forceful insulin delivery to cut through the tissue and deliver insulin deep enough.

In my 20+ years pumping, I’ve used Minimed, Animas Ping, Animas Vibe, Omnipod, Snap and TSlim. Both Animas and Minimed delivered most forcefully. Snap was in the middle. Omnipod and Tslim were too gentle and both gave me frequent occlusions. Though I love the TSlim and Omnipod technology and features, I cannot handle the soft delivery and resulting occlusions. While I don’t understand the design reasoning behind TSlim’s slow delivery, I wish they would offer a fast-delivery option to customers so more of us can enjoy their beautiful pumps.


@Sally7, I’m glad you were able to get relief from occlusions by using the metal infusion sets. I also swapped out my Comfort Shorts for the metal sets you described, but continued getting occlusion alarms. I wonder if anyone has found occlusion improvement with the X2 upgrade.


I have been on the X2 for six days and have had two occlusion alarms. Each time I straightened out the tubing, hit resume insulin and all was ok. I use a tiny amount of insulin.


After about 10 years on Medtronic pumps, I switched to the Tandem X2 about 3 months ago and since that very day, I’ve have had a lot of issues with the X2. With Medtronic I had about 1 occlusion a year. Now I have 1 occlusion alert per infusion set. I have tried every infusion set Tandem sells: T90, T30, Comfort Short, and Contact Detach (steel cannula) and I’ve tried them on multiple places on my body. The pump has reported occlusion alerts on each and every set, each and every time. I even had an occlusion alert when the pump was disconnected, sitting on the counter. Most of the time I can clear the alert and continue with a new bolus and it works fine the second time but sometimes it will continue to report an occlusion. Every time I’ve taken out the set and looked at it, the cannula looks fine and the site looks fine. Reading that others are having the same problem makes me feel like this is possibly just a design flaw in the Tandem pump. Speaking to Tandem Tech support has not been terribly fruitful as they continue to point the finger at everything besides the pump. It looks like this is up to me to solve or to go back to my medtronic which, while not exciting, was extremely reliable. I’ll continue to experiment with new sites, who knows maybe I’ll get lucky. When the medtronic did very occasionally have an issue they always overnighted me a new pump with no hassle. Tandem tech support has refused to send me a new pump. I’m guessing this smaller, newer company that has yet to show a profit can not afford to replace pumps that are showing this issue. This really saddens me because I really want to love the X2. It’s great in so many ways but it’s unreliable at the most crucial job: pumping insulin. I would love to hear how others have solved this problem on a T-Slim or X2.


Argh. This is distressing and really make-or-break for me. I’m at the four-year point with my first pump, a Medtronic, after 30 years on injections. I had a brief 3-month sojourn with an Assante Snap pump before they went out of business and loved everything about it EXCEPT the frequent occlusion alarms. Drove me crazy–couldn’t get through a night without getting zapped awake multiple times. They said “scarring” and had me switch to angled infusion sets and that fixed it but those things have their own problems–take up a LOT more real estate, painful, harder to insert, etc. The real problem was that the occlusion sensors were just too damned sensitive. T:Slim is attractive to me because of the interface, but especially because of the remote software update capability–LONG overdue in this industry–which is huge given that we’re locked into these things for 4 years, which is to say, locked OUT of improvements for four years. But I’ve already gone through being zapped awake multiple times a week because of hypersensitive occlusion sensors. I’m not thrilled about Medtronic–I made the decision to use Dexcom some time ago and I’m not interested in changing my mind about that, which obviates their current selling points about semi-closed loop capability–but the occlusion thing? I really don’t want to go there again. Damn.


I got an X2 right when it came out. Sent the first one back due to multiple occlusion alarms. New pump has been better. I wear dress slacks to work and have button holes cut in the pockets. Pump goes in the pocket and tubing goest thought the hole and up to the set which is usually in my abdomen. I’ve found that my belt can pinch the tubing. I only get he alert during bolus and I just deactivate the pump, dispense the remaining insulin and get on with my day. I know everyone says you need to change the site, but this works for me. I think the pump is just a little too sensitive to the back-pressure


Is that with a Tandem pump or something else?


no, Accu-chek, which unfortunately has recently announced it’s not taking new customers


Dang. I so want to be reassured about T:Slim but that hyper-sensitive occlusion thing just depressed the heck out of me when I had the Snap and I don’t want to go back to that feeling. Trying to convince myself something’s ok when it isn’t because so much else about the pump was great. I don’t know why but that experience put me in the worst T1 funk I’ve been in since the first few years after DX. I think that was when I coined the term “T1 claustrophobia” for how it felt. Kinda left a mark…