Thinking of getting a Tslim for my next pump

My total basal is 2.375u. I was wondering what others think if my basal amount is too low for the delivery system on the tslim? My basal program reads as: 12a-5a .050,
5a-10a .175
2p-9p .125
9p-12a .025

The t:slim x2 allows you to change basal in 0.001 increments, HOWEVER, there’s a minimum basal of 0.1u. There’s also a minimum cartridge fill volume of 50 units, which may or may not be too much for you. If this doesn’t meet your requirements, they do make insulin dilutant. It’s basically expensive saline that’s pH buffered to match the insulin. You could dilute your insulin 50/50, and then basically take twice as much.

I’ve been on the x2 for two years now, and I’m THRILLED with the system. There’s a few annoyances, like the FDA-required redundancies, but every one is worth it to me.

I don’t have any first hand knowledge of it, but I do know the omnipod is approved for very young children, so it might have settings that match your minimal needs. Either way, I hope you find something that works for you.

Actually the Omnipod settings are not as precise as Tandem.

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I think Laddie is right. But, should double check the study that cites the error in Omnipod pump delivery - its called the siphon study. I don’t have anything for T:slim.

I am very interested in the tslim pump but I still have 13months to go before I can get it. I have heard people say that it doesn’t work if you are on a low dose of insulin. My daily requirements are between 12 to 14 units a day. The only thing I am not sure about with the tslim is the cartridge change process. I was on an animas for 12 years and now the 630g so I have only had the plastic cartridges. I used medtronic’s enlite sensors for about 6 months but went back to using dexcom. I have read many posts of people saying how they used medtronic’s crappy sensors but always ended up switching back to dexcom. They have a great product. I am using the g6 along with my 630. I would love a pump and a cgm that talked to each other and regulated my basals and high bloodsugars. My main reason for wanting the tslim is the cgm part of it. I also want something that can be updated so I don’t have to wait for the latest and greatest update. With it being a touchscreen that is just an extra. How long did it take you to get adjusted to the tslim? Did your settings change that differently? As I can see that is the only pump that talks to dexcomg6 except for the omnipod which I am not too crazy about.

I had forgotten about this study which was published 10 years ago. They did measure significant differences of actual insulin delivery depending on the relationship of the pump position versus the infusion site position. When the pump was higher than the site, over-infusion occurred and when the pump was lower, under-infusion resulted.

These variances affected most the people who were most sensitive to insulin and only needed small amounts, like young children. I have worn an insulin pump for almost 33 years now and have never considered this phenomenom.

The study did say that in people with higher infusion rates, the other things that affect blood glucose levels such as tissue permeability may overcome any effect that pump position may play. My experience of this effect is likely also influenced by the fact that I have always worn my pumps on my belt and infused just above belt height.

Your basal rates are unusually low, @Dee_Meloche. If it were me, I might risk getting a Tslim pump but would make an effort to keep the pump at a similar elevation to the infusion site in order to avoid this effect.

I also wonder if closed loop systems like Tandem’s Control-IQ that the Tslim can use may counteract this siphon effect.

This is my first insulin pump in 30 years, so I didn’t have the adjustment period most will face with the t:slim. They tried to give me one when I was first diagnosed at 8 years old that weighed nearly as much as me, and I wasn’t having anything to do with it. I had been on MDI ever since, with miserable control, I might add. In general, people aren’t very good with change, though, so I can understand why some people have trouble making the change or show brand allegiance.

I have a molecular and cellular biology background and even worked as the chief science officer for a medical device company for 12 years, meaning it was my job to appease our FDA liaison. I know more about the FDA workings than probably anyone on this board, and how they handle medical devices, and I don’t trust them for anything. What they do has very little to do with ensuring safety, and everything to do with business politics, lobbying power, and bankrolling the existence of the FDA. Did you know you can flat out buy the “FDA listed” designation, and put that shiny, familiar FDA logo all over your marketing that everyone automatically associates with safety? FDA-registered devices are handled differently. The first thing our FDA liaison asked us was if we wanted to be a “big dog” or a “little dog”, meaning how much money were we bringing to the dog-fight and did we want the lobbying power to go up against the reigning “big dog”, it didn’t matter that we had a far superior product, it was all about the bankroll.

Because of all the aforementioned, I was exceedingly neurotic about my insulin pump research. I researched all of the adverse reported events. You can do so yourself at MAUDE here: httpsss:// But I warn you, it’s a lot of technical jargon to get bogged under, but enlightening if you’re willing to spend the time. There is an European equivalent, eudamed database, but it wasn’t accessible to the general public when I did my research, though that is supposed to be changing. I wanted to know about the algorythyms used and had some programming questions. My local Tandem rep was able to get someone from the development team to call me and answer all my questions and even forward me data, while Insulet and Medtronic reps were either slow go-betweens with info, or flat out refused my requests. I was furthermore impressed with Tandem’s willingness to play well with others. They partnered with TypeZero and were willing to learn from the existing diy closed loop community what was already working for them, building on the past experiences of others. I LOVE that the t:slim is rechargeable and touchscreen, just like all my other familiar devices. Heck, I even drive an electric plug-in, why shouldn’t my insulin pump plug in? I also think the ability to update the T:slim is a game changer for the industry. I’ve done so twice now, and am looking forward to Control-IQ this month.

Honestly, though, Insulet’s omnipod was eliminated quickly just because they had a hard time delivering the promo kit to my rural address. I’m not making a 3 hour drive every month to retrieve my supplies!. They may have fared better in my research had they not been eliminated so quickly. And I’m definitely a champion of the underdogs when it comes to medical devices. They’re fighting so hard just because they’re passionate about bringing forth a better technology, and it is a FIGHT. So, Medtronic started with that demerit. I would have over-looked that bias if the research proved they had the best device for my health and safety, though.

When it came down to it, I was excited for Tandem and disgusted with Medtronic. I honestly believe Medtronic dominates the industry just because they are such a massive company with equally massive influence. People stay with what they know, doctors stay with what they know… It’s just easier that way. The reality is that their technology is stagnant, and they have a history of rushing to release a sub-par product just to be the first and sweep up that share of the marketplace. (My reality? I know there are others that will disagree with me here.)
Based on the current available options, I’m a Tandem girl all the way. I’ll be repeating my research all over again in a few years when I’m next eligible, though.

If insulin volume is your only concern, seriously look into getting the dilutant. It’s readily available, though I know nothing of the cost. I assume it’s also covered by insurance. I used it once upon a time in my honeymoon period when I was really low dose still. It’s just the safest way to water down your insulin, so you can easily deliver a bigger volume.

A lot of people complain about the cartridge fill experience. I think the description and tutorials make it look worse than it is, though. Once you do it a few times, you’ll realize that the whole thing becomes second nature and only takes a few minutes. I need about five minutes total to do the full site/cartridge change

Sorry, I’m long-winded!


I’m pretty sure the micro-delivery method of the t:slim renders this a moot point.

Yeah, I think I might take the risk and try it out when I am able to if nothing better comes out. If medtron’s 780 connects to the g6 and is updateable I would probably go with that. Those are the two main reasons for wanting the tslim.

@Robyn_H - This alone grabbed my attention, as well as my instant respect.

I humbly offer you any pumping tips I might share to ensure your experience with your pump is a +’ve one.

Thank you so much. I’ve got it pretty much figured out now, but I’m always reading here for more insight. On MDI I struggled to keep my a1c under a 13, got it down to an 8 with Tandem and the switch to analog insulin (yay for better insurance!), and 6.1-6.4 with dexcom G6 and basal-iq. So for now, I’m just as pleased as could be. Though admittedly, I still need more practice avoiding the post-prandial spikes, but setting a really high temp basal rate is helping there.

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@Robyn_H . I found by being a bit more aggressive with my pre-bolusing I could virtually eliminate most post-prandial spikes. That and switching from Humalog to FiASP, allows me to run normal night-time BG and to run near normal A1C’s.

My secret to success is to focus on each day and attempting 100% time in range.

I hadn’t thought of that @Robyn_H. It appears that Tandem’s design effectively isolates the reservoir from the infusion set. If true, then that is a moot point. The only reason I tentatively state, “if true,” is that I don’t think the tslim pump has undergone a study like the 2010 set-up details.

Fair point. I don’t know of any study off-hand. I did mention a few specific “adverse events” surrounding pump malfunctions and resulting severe hypoglycemia when I spoke with the development team, which is how I know that this micro-bolusing was specifically designed to avoid potential over-delivery… But I don’t know if it was specifically tested against gravity and wasn’t aware of that study when I asked my questions.