What is an Insulin Pump?

Type 1 diabetes is an autoimmune disease which renders the pancreas unable to make sufficient insulin to meet the diabetic's needs, rendering them dependent on injected insulin. For many diabetics, this means giving themselves several injections every day. The advent of fast-acting and extended time-release insulins has improved the control that diabetics have over their blood sugars, but has also increased the number of injections required in a day. An insulin pump provides a diabetic with even tighter control of their blood sugars, while removing the need to treat the disease via injections.

An insulin pump is a device about the size of a pager, which can be conveniently carried in a pocket, on a belt clip, or in another discreet place on the body. A line carries insulin from the insulin pump into the person's body, where the tip of the line, called the cannula, is inserted just under the skin and taped down. This tiny catheter must be changed every couple of days, and can be changed by the diabetic; most diabetics report that inserting the cannula is relatively painless, certainly preferable to injecting insulin every time it is needed.

The insulin pump affords much greater control over diabetes than traditional injections. An insulin pump uses fast-acting insulin, which flows slowly but steadily into the diabetic's system in a manner that imitates the function of the pancreas. This flow is called a basal rate and accounts for the sugars released regularly into the bloodstream from the liver's sugar stores. Accurately estimating this rate of insulin flow may take some trial and error, as well as guidance from the diabetic's doctor.

Aside from the basal rate, however, additional insulin is needed whenever the diabetic ingests anything with carbohydrates, which the digestive system quickly breaks down into simple sugars for use in the body. To prevent the diabetic's blood sugar level from spiking, the diabetic programs the insulin pump to release the appropriate amount of insulin, in addition to the basal rate. This amount is called the bolus.

Diabetics on a regimen of injected insulin not only have to take a separate shot every time they need insulin, but they also have much less immediate control over their blood glucose levels. There are two basic forms of treatment via injection. The traditional treatment plan requires two or three shots a day of slow-acting insulin, which must each be taken at the same time each day. The traditional treatment plan also requires that the diabetic eat meals at the same times each day, each containing a very specific amount of carbohydrates, so that his or her blood sugar remains at a constant level. The more modern treatment plan, made possible by new forms of insulin, requires only one daily shot of 24-hour insulin, but also means that the diabetic will have to take a shot of fast-acting insulin with every meal, snack, or drink that contains carbohydrates.

Although the latter treatment plan allows much greater control of the diabetic's blood sugar levels than the former, there are still limitations. Once the injection of 24-hour insulin is in the diabetic's system, the control is out of the diabetic's hands. During physical activities, the body uses insulin much more efficiently, so unless the diabetic eats a carbohydrate-laden snack, without correcting with the normal injection of insulin, the diabetic's blood sugar levels can fall dangerously low. With an insulin pump, however, the diabetic can simply program a temporarily reduced basal rate, or even disconnect from the insulin pump entirely while they remain physically active. Thus, programming the insulin pump affords diabetics a greater flexibility in self-treatment than they have ever had in the past.

Each advancement in the technologies used to treat diabetes comes closer to imitating the function of the pancreas, which the diabetic no longer has. The first miracle was to copy the hormone the pancreas produces -- insulin -- so that diabetics could survive without being able to produce it naturally. Modern insulins allow treatment to more closely mimic the work of the pancreas, as long as the diabetic is willing to give himself an injection each time the pancreas would normally be releasing insulin.

The insulin pump has come even closer to mimicking the actions of the pancreas, as diabetics who wear the pump need only program the device with their needs, and the pump will do the rest. The only pancreatic function that an insulin pump cannot yet handle is the monitoring of the body's blood glucose levels; diabetics still have to do so manually. However, as rapidly as technology is advancing, it will not be long before an artificial pancreas -- a device that can both monitor blood sugar and release insulin accordingly -- will enable diabetics to live perfectly normal, healthy lives.