Introduction
People who do not have diabetes have a functioning biofeedback loop in their bodies that keeps a small amount of insulin in their bloodstream at all times to keep blood glucose levels steady. When they eat carbohydrate-laden meals, their bodies release even more insulin into the bloodstream to protect them from spikes in blood sugar. This does not happen in people with type I or type II diabetes. Historically, people with diabetes have had to manage their blood glucose levels with multiple daily injections of insulin---one or more injections of long-acting insulin to keep baseline blood sugar levels steady and another injection of insulin to cover meals. This has recently changed, as insulin pumps have given more freedom and flexibility to those living with diabetes.
What Is an Insulin Pump?
Insulin pumps are small, cell-phone sized devices that deliver insulin continuously throughout the day to keep blood glucose levels stable. The electronic device is programmed to deliver insulin through a tube that is thinner than spaghetti into a catheter that is inserted under the skin. The catheter is typically inserted in the abdominal region, while the electronic programming monitor is worn in a pouch clipped onto the belt or waistband. Some insulin pumps have recently become wireless, making it easier to dress because there are no tubes to tangle or hide, and the electronic programmer can easily be slipped into a handbag or backpack.
Programming the Pump
Patients with diabetes who begin insulin pump therapy work with their diabetes care teams to program their individualized insulin delivery. First, they must calculate the average insulin they use over several days. Approximately half of this insulin will be programmed into the pump to be delivered as basal insulin---the baseline amount of insulin in the bloodstream at all times. The other half of the daily insulin will be programmed as bolus insulin---the insulin delivered when eating to avoid blood glucose spikes triggered by carbohydrates.
Correcting for Food and Activities
People on insulin pump therapy may program different basal insulin delivery amounts depending on their activity or time of day, and the pump will automatically increase or decrease the insulin amounts at the programmed times. For instance, if someone has a tennis match scheduled before dinner, she can reduce her basal insulin to avoid hypoglycemia, or a low drop in blood sugar. When she eats dinner after her tennis match, she will program her pump to deliver the amount of bolus insulin required to cover the carbohydrates in the food she is consuming and increase her basal insulin level back to its normal setting.
Conclusion
Insulin pumps not only eliminate the need for multiple daily insulin injections but deliver insulin more accurately and improve blood glucose levels better than injections. They also allow people living with diabetes to enjoy a variety of foods and activities without worry---they need only push a button on their pump to cover any type of meal or physical activity.
