By: Katherine Marple
One of the greatest technological advancements in diabetes care has been the insulin pump. For one, it gives you the illusion of being “normal” because you no longer have to inject insulin throughout the day. Instead, you “bolus” by pushing a button on the pump itself or using a remote control. It allows better glucose management because you can adjust your basal rate (the “background” insulin dose) by increments of one thousandth of a unit every hour. Especially when you’re moving from the peaks and valleys of NPH or the restraints and hazards of Lantus, the freedom of living with an insulin pump is incredible. But pumps do not come without their kinks.
Most people in the diabetes community know what a pump is, but for those who don’t, I’ll give a quick overview. A Medtronic MiniMed insulin pump, for example, carries about 200 units of fast-acting insulin in a machine about the size of an early pager. The insulin moves from the pump via a tube that is connected to your skin through a cannula. The cannula is inserted into your subcutaneous layer via a two-inch needle. After insertion, the needle is removed and the plastic tube remains under the skin, held in place with sterile medical tape. The pump pushes insulin through the tube into your body in increments as small as .05 units per hour. Pumps like the OmniPod don’t even have a tube; they’re connected directly to your skin after being pre-programmed with your insulin requirements. When you’re using a pump, you no longer require insulin injections via syringe and you no longer use basal insulin (NPH, Lantus, or Levemir).
I have learned many lessons while on the insulin pump. For example, I learned how my body reacts to the Dawn Phenomenon, that early morning rise in glucose levels that occurs when the liver dumps glucose into the bloodstream to prepare the body to awaken. I found that my body begins this process as early as 4:00 AM, so I need approximately two extra units of Apidra (the fast-acting insulin that I have relied on for the past six years) per hour to keep my glucose from shooting outside my target zone. At 7:00 AM, my basal needs are adjusted back down to my normal “daytime” rate.
I have also learned that to avoid insulin shock in the middle of the night, I need to lower my basal rates by a half-unit per hour from midnight to 3:00 AM. With these kinds of needs, you just can’t maintain a consistent glucose level throughout the night using injections and a basal insulin such as Levemir (my personal trusted basal insulin) without waking in the middle of the night to test and correct.
I used the Medtronic MiniMed insulin pump (as well as many samples of the OmniPod) for almost three years. During that time, I learned incredible things about how my body reacts to foods and how intricate an insulin regimen I require to keep a balanced A1C. Using the insulin pumps helped me to find my unique treatment path.
However, I also came upon the harsh reality that I cannot depend on anything but myself to survive this mean beast of a disease. The main issue I have with the insulin pump is that it uses only fast-acting insulin. With multiple daily injections, if you inject into a poor injection site, at least you have the background basal insulin that is injected once or twice per day to get you through until you can inject another bolus shot. The basal insulins act as a buffer to make sure that your glucose levels never get too far out of control.
Fast-acting insulins, such as Humulin R, Apidra, and Humalog, stay in the bloodstream for a maximum of only four hours. Let’s say you have a pump malfunction and you don’t receive any insulin. After four hours with a malfunctioning pump, you no longer have any insulin whatsoever coursing through your veins. This, of course, leads to the extremely painful, scary, A1C-shattering, and life-threatening condition of ketoacidosis.
Once I was fast asleep when my Medtronic pump malfunctioned and stopped delivering insulin. It also failed to sound an alarm to let me know that it had stopped working. When I woke five hours later, I was already in full blown ketoacidosis and was rushed to the ER. I ended up staying in the ICU for three days while my levels were re-adjusted. I notified Medtronic of the malfunction, and they promptly sent me a replacement pump.
A few months later, now using the new Medtronic, I was working at my office desk when my pump malfunctioned again. Once again, it didn’t sound an alarm that it wasn’t delivering insulin. This time, however, I could feel my glucose levels rising. Because I was awake, I was able to test my glucose on my meter and notice the steady increase as time went by.
After the first hour, I simply input a few units of bolus, hoping to bring down my level that way. I didn’t realize that my pump was not delivering insulin because no alarm had sounded. At the second hour, still not realizing that the pump wasn’t pushing any insulin through, I used my back-up syringe to dose a small bolus of Apidra. By the third hour, however, my glucose was still rising.
Finally guessing that the pump wasn’t working properly, I discarded my cannula set and changed out the reservoir. I primed the pump and re-inserted a new cannula under my skin. By this time, however, more than three hours had passed without insulin delivery and I was already in the throes of another episode of ketoacidosis. I was driven to the ER and enjoyed another three-day stay in the ICU.
I haven’t been back on the pump since then. I later learned that my difficulties with the pump may have been because I am allergic to the cannula that is inserted under the skin. My endocrinologist believes that I have an allergy because although it has been six years since I’ve used an insulin pump, I still have snakeskin-like bumps across both sides of my stomach where I used to do the majority of pump insertions.
I never had a set in place for more than three days at a time, usually changing it every two days. I tried using my abs, my lower stomach, my thighs, my hips, the upper flesh of my butt, and my lower back (even trying the back of my arm with the tubeless pumps). Every site had failed absorption rates, sometimes infecting within just one day and sending blood back up into the tube that was connected to the pump. In the end, the two threats to my life in a few short months, not to mention my steadily rising A1C and the endless frustration and pain, were just too much. I haven’t been able to trust my life to a computer since.
At least when I’m injecting via syringe, I know that the insulin is delivered because the syringe comes back empty. If I inject into a bad site that has low absorption, then I still have Levemir in the background to save me from ketoacidosis, and I can inject another dose via syringe in the next hour in a new site. To battle the Dawn Phenomenon, I wake in the middle of the night and check and correct.
It’s inconvenient, but so was having failed pump sites, infected cannula scars, and ICU stays due to a failed pump signal. Having insulin-dependent diabetes is inconvenient, in general. I just can’t bring myself to trust anyone but me to manage my diabetes. That includes a machine, no matter how many other people swear by its design.
The lessons I learned about myself and my body while using an insulin pump are priceless. I doubt that I would have the stellar control that I have today, six years after discontinuing the pump, without first trying to use one. While I don’t blame the pump manufacturers for my disappointing experiences, I have made my decision to steer clear of machines that deliver the insulin I require to keep breathing. Although the insulin pump is an incredible advancement in diabetes care, it is still just a computer attached to your body. In my 14 years with type 1, I’ve tried just about everything available on the market. While the insulin pump is a huge help for some, it is a cure for none. I’m still asking and waiting for more.