Pumping 101

Time for a new set. I’ve gotten disorganized and ParaPump has been warning me that I’m running on empty. A quick check of the pump status screen shows me I’ve got juice for six hours of basal. It is after 10pm…I’ll run dry at four in the morning. I think I’ll change my infusion set tonight instead of in the morning. It gives my bride, who’s usually snoozing during site changes, an opportunity to check out the new gear. I spread out the tools of the trade on the kitchen table.

Reservoir. Check.

NovoLog vial. Check. Looks like there is just enough left for one more fill up of my 522’s baby 176 unit reservoir.

Quick-serter. Check.

IV3000 and new lancet needle. Check and check.

Reservoirs come individually wrapped in long perforated sheets, like an ammo belts for those big machine guns. You can tear them off one at a time. I think ten or so come in a box. For those of you new to pumping I’ve probably done you a disservice in not laying out more clearly how the whole system works. The reservoir is the clear plastic syringe-like cartridge that holds the pump’s insulin supply. You fill it to suit your needs for a three day period. It is one of the disposables. The pump will drip little bits of the fast acting NovoLog or HumaLog into your body 24-7, 365. This covers your “basal” needs.

Basal is the insulin that keeps you alive between meals, at night, and when you are lost on a deserted island with nothing to eat. When you eat you need either a lot more insulin, a whole lot more insulin, or tons more insulin—depending on how much you are eating and what you are eating. This meal time insulin is called Bolus insulin. In a pump, the two types of insulin are the same juice, the only difference is in how it is delivered.

You figure out your basals needs by time-consuming trail and error. Some people can get by with one “rate” all day and all night. Most people need different rates for different times of the day. We call these different rates the “steps” of a “basal pattern.” Again, one size doesn’t fit all. Most folks have four to six steps. I happen to have 18 steps throughout the 24-hour day. Once your pattern is established you can program it and forget about it. The pump will handle this part on its own. Of course you can increase it or decrease it at will using a feature called a Temporary Rate. For instance, on days that I work at the clinic I get so jazzed by the excitement of the work that my sugars skyrocket. I’ve found that using 150% of my normal basal rate for ten hours usually does the trick. Other, more athletic folks will use lower rates while they are working out.

Bolus insulin takes some work to figure out too. In a nut shell, you need to know or guess how many carbs are in the food you are going to eat. Carbs are various types of sugars, both natural and un-natural that are in most foods. Carbs impact blood sugar very quickly, which is why we worry about them. Type 1 Diabetics need to “cover” the carbs we eat with insulin. Every time you put something in your mouth you’d better be pushing buttons on your pump. It sounds like a lot of work, and it is. But funerals are a lot of work too. A quick and important point. The pump is NOT an artificial pancreas. Nor does it serve as a replacement for your brain. Even with CGM, the pump part of the pump doesn’t know what your blood sugar is. Just because your sugar is displayed on the screen doesn’t mean your pump is any smarter than you are. You must tell your pump what you want it to do. Even with our fancy CGM and B-wiz, the pump is just a time saving tool, not a miracle. You must think about what you are doing. You must tell the pump what to do. They are working on closed-loop pumps, but it’ll be quite a few years until your Doc can write you a script for one.

Anything you are eating out of a box will have the carbs printed on the side or back. Some things are “free” of carbs. Modest amounts of protein, for instance. So you can eat anything that runs, flies, swims, crawls, or slithers without taking insulin. Cheese is safe too, as are most veggies in small amounts (beware corn and carrots!). For real food there are a ton of resource books you can use to look things up, and in time you can get pretty good at estimating by looking. In more time you’ll get lazy and be wrong more than you are right. One of my crew (I’ve trained three of our best “control enthusiast” patients to become Diabetes Peer Educators at the Clinic) has a great set of about a thousand food flash cards. He has a blast doing carb drills with other diabetic patients.

Usually basal is half the total insulin you use in a day, and the other half is bolus. Excepting days that you find yourself at the all-you-can-eat buffet and China Star, you generally use about the same amount each day. You fill your reservoir with that much plus a little extra, just for in case. Or maybe you don’t. Depends how well your insurance covers insulin.

MedT has built a better mouse trap with their Paradigm reservoir. It’s topped with a (you guessed it) blue plastic “transfer guard.” The guard is the best thing since saran wrap. It is a little bracket that securely holds the reservoir in alignment with the vial of insulin. It reminds me of the little docking collar they used for the Apollo/Soyuz rendezvous back in ’71. Ya just snap the insulin vial onto the top of the collar, pressurize the vial by pushing down the reservoir’s plunger, tip it vial-side-up and draw the insulin into the reservoir. Slick.

The transfer guard even places the needle just inside the vial so you can suck it dry. OK, I gotta admit it. I’m really liking the MedT Paradigm infusion set system. The whole kit and caboodle, and I’ve never had fewer bubble head aches! I like the little baby reservoir that actually is the size I need.

Next Time: more on pumping and the MedT ParaPump system parts and pieces.