I'm new to an insulin pump! What do I need to know?

I was diagnosed with T1D almost a year ago and am now using a pump. I went with a t:slim. So far I am LOVING it and it’s only been three days! I don’t know much about insulin pumps besides what I was trained on. Does anyone have any tips and tricks to their t:slim pump? Is there anything you wish you would have known when you first started using a pump?

I’m not sure how much you know overall about insulin dosing in general, so please excuse me if I’m telling you something you may already know.

The first thing you must realize is that the pump is just a fancy syringe. The real brains behind making it work well is you. While learning about your T:Slim will help, the more important knowledge is about things like the onset, peak, and duration time for the insulin you use. Read the insulin package insert. You need to understand roughly how your insulin on board quantity is calculated and how it affects your dosing. I would read a least a few books on using insulin and pumps. John Walsh writes Pumping Insulin and Gary Scheiner authored Think Like A Pancreas. Read your T:Slim user guide at least twice - cover to cover.

Be ever-aware that since you are only delivering fast acting insulin, you are vulnerable to quickly slipping into real trouble if a site becomes fouled or otherwise not absorbing well. Using a pump means you need to more vigilant with monitoring your blood glucose levels than you were on MDI. You should be consistently fingersticking many times per day or better yet, using a CGM.

Acquaint yourself with some of the more advanced techniques like super bolusing, extended bolusing, and combo-bolusing. Tandem may use slightly different terms but these functions are explained in the books I listed above. You want your insulin action curve to ideally match your food action curve. One of the best ways to do this is to take your insulin in advance of your meal. This is called pre-bolusing. How much in advance? Like all things with diabetes, it depends. The best way to discover the ideal time is to test yourself. Fingersticks at appropriate times and writing down this info will help you to discover a good prebolus time for you. It may be longer in the morning than it is later in the day.

Develop an attitude of seeing insulin dosing as an ongoing science experiment. It is the best way to get things customized for you.

Don’t look at any of the settings on your pump in a “set it and forget it” fashion. None of those settings are sacred. Our metabolisms change and unless we’re willing to change with them, it’ll be harder to keep things under control. I regularly make changes to my basal profile.

If your blood sugar starts rising and keeps rising and you can’t attribute it to something concrete, consider changing the site and starting fresh. Sites can go bad or you may have a bent cannula or some other delivery impediment. Don’t stick with any site too long. Instead be quick to change. It’s much better to change too soon than too late.

If your BGs rise over 300 mg/dl, deliver any corrections with a syringe.

Always have your supplies with you to do a complete set change. I try to carry three sets with me. If you only have one back-up and that back-up fails for some reason, you’re stuck. Murphy’s law rules, especially with diabetes.

If you get an unexpected fingerstick number, real high or low that will require adding lots of insulin or carbs to treat, wash your hands and do the fingerstick again. In fact, always wash your hands before doing a fingerstick.

Always carry at least one extra battery for your pump.

I’ve written more then enough but there are other things. Pumping is a wonderful way to dose insulin. Good luck!


Excellent advice from @Terry4 above!

The main thing I would add at this stage is that the key to getting pump therapy to work well is getting your basal rates set as accurately as possible. The ONLY way to do this is by tedious basal testing. Your pump trainer and/or the DSN/CDE at your clinic should have instructed you in how to do this (and hopefully should be available to assist or give advice). Unfortunately this is often not the case - if so you can still work this out yourself. There are plenty of posts on this and other Diabetes sites explaining how to do this. You can do it using fingersticks BG testing. However if you can use a CGM this makes it much easier AND more precise. The T-slim pump should integrate with the Dexcom CGM - talk to your doctors to see if they will provide you with a system, even if it is just a loaner.

As a recently diagnosed T1, you probably still have some residual beta cell function. This will actually assist controlling your basal requirements and make setting basal rates on your pump a whole lot easier. Most people have multiple rates that differ depending on time of day (sometimes 8 or more segments). so it can take time to get it right.

All the best, and remember, if you have any questions, there are people on this board who have the T-shirt.


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My tip would be to take care to rotate your sites well with every set change. I was told never to go within a square inch of a previous site within a 30 day period.

Know what insulin smells like. If you happen to have some leakage at the site, you’ll want to change out immediately.

Let us know if you have any questions, we are here to help!


A really helpful book is “Pumping Insulin” by John Walsh. A lot of people consider it the pumping bible. It covers everything, read it & then keep it around as a handy reference. You can find it on Amazon or the Diabetes Mall (www.diabetesnet.com) which is John Walsh’s site & has a lot of good information & tips for pumpers.

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Good advice from all of the above. Nothing to add here, just take the advice to heart.

In my case, with the tslim, I realised I have to look at the luer-lock once a day (and make it tight again) and inspect for bubbles at least once a day. I usually do a flush of a 1-1.5 inches bubble per infusion set.

sorry I’m, on the OmniPod. but i do find, out i can trouble sooner, with my.

When it doubt, change it out. If you’re experiencing some higher-than-normal BGs and are not coming down with pump corrections, change out your site. If your BG rises about 250, it’s a good idea to do a ketone check to make sure you’re receiving insulin. If the ketone check comes back positive (you’re urinating ketones, or blood ketone levels are above a certain threshold -I use urine ketostix and am not sure what the threshold is for blood ketones), change out everything on the pump and administer a syringe correction.

With basal rates, remember that it’s going to take 1.5-3(ish) hours before that basal insulin starts affecting BG levels. If I perform a 9AM-3PM basal test and see a gradual trend upward, I’ll need to modify my basal from about 7AM-1/2PM. This is also important to know for temp basals -I have experienced too many lows from me lowering my basal and immediately going for a run (and not remembering that the lowered basal won’t “kick in” for a good 2 hours, and I’ll need to supplement any physical activity with carbs before then).

In terms of the TSlim, the fill tubing process takes quite a while. I like to insert my site before I begin the load process, disconnect myself to fill the tubing, and then can walk around the kitchen and get other stuff done while the tubing gets filled (the fill tubing process takes about 2-3 minutes). One of the cooler things I saw recently with the TSlim is people using one of those portable phone chargers to charge their pump while they’re moving around and getting stuff done (you don’t need to disconnect to charge the pump, but it takes about an hour for my pump to go from 50% to 100%).