When you have diabetes and rely on insulin to help control your blood sugar, insulin administration can mean multiple daily injections of insulin. Insulin pumps can serve as an alternative. Instead of injections, the insulin pump delivers a continuous, pre-set amount of insulin, plus bolus doses when needed. While you must still check your blood sugar levels, the pump can take the place of multiple daily insulin injections. While insulin pumps are not without their disadvantages, they can help some people with diabetes obtain better blood glucose control.
An insulin pump is a small device that closely resembles a beeper or miniature computer. Slightly smaller than a deck of playing cards, the insulin pump has several key components:
- reservoir: the reservoir is where the insulin is housed. This must be refilled periodically to ensure a steady stream of insulin.
- cannula: a small needle and straw-like tube inserted subcutaneously, or fatty tissue under the skin, that delivers insulin. The needle is withdrawn while the straw remains. You must switch out the cannula and its site periodically to reduce infection risk.
- operating buttons: These buttons program insulin delivery throughout the day and also deliver mealtime and bolus doses.
- tubing: thin, flexible plastic that transports insulin from the pump to the cannula
For some patients, wearing an insulin pump provides more flexibility to administer insulin doses on the go without the need to carry many diabetic supplies.
Insulin pumps offer two dose types. The first is basal rate, which is a continuous infusion that delivers a small amount of insulin throughout the day. This insulin helps keep your blood sugar levels stable between meals. The other, called a bolus dose of insulin, is given at meal times to help keep blood sugar levels in their target range after you eat a meal.
Your healthcare professional will help you determine both basal and bolus dose amounts based on your blood glucose levels, the time of day, your typical daily routine, and your insulin needs
Wearing an insulin pump means that you must maintain the pump and the pump site. You must alternate your pump’s location every two to three days to avoid infection. You must also refill the insulin reservoir as needed. To make it easier to remember, each time you change your infusion site’s location, plan to change or refill the insulin reservoir within the pump.
Several different manufacturers make insulin pumps. Read your pump’s instructions carefully to ensure you are using your insulin pump appropriately.
Insulin pumps are a safe and convenient way to deliver insulin and maintain blood sugar control, provided you use them carefully. However, they are not for everyone. Insulin pump users must test frequently and understand how to count carbohydrates so they can determine how much insulin they need at meal times. They also must manage their activity level. Although it may seem easier, using a pump takes dedication, and only those who are ready to commit to regular testing and close management of diet and exercise should consider using a pump.
Some of the risks associated with insulin pumps include:
- added training needed to properly operate the pump
- expense associated with purchasing and operating the pump (although some insurance plans do cover some of the costs)
- possibility for skin infections
You must also continue to check your blood sugar levels at least four times daily. This can alert you to the fact that the tubing or cannula has detached from your skin or has become clogged..
Also, you must disconnect your pump when you are exposed to water or excessive sweat, such as when taking a shower, swimming, or exercising in hot weather. Because the cannula is protected and held in place with an adhesive covering, the water can make the adhesive wear off and dislodge the cannula. You must remember to re-apply the pump after water exposure. Talk to your health care team to decide when to disconnect and determine how long you can stay disconnected. Most people should not disconnect from their pump for more than two hours at a time.
This information is a summary. Always seek medical attention if you are concerned you may be experiencing a medical emergency.
Some insulin pumps on the market are equipped with continuous blood glucose monitoring (CBGM) systems. This means the insulin pump can monitor blood sugar levels without the need to check with a finger stick. According to the American Diabetes Association 2014 Clinical Guidelines, combining insulin pumps with CBGM helps to reduce blood sugar drops at night ( nocturnal hypoglycemia) without impacting a person’s A1C levels. CGM does not completely eliminate the need to test your blood sugar. You must calibrate the meter twice every day to be sure the CGM is accurately measuring blood sugar levels.
However, this does not mean the insulin pump acts as an “artificial pancreas.” This is because researchers have not created an algorithm to program the insulin pump to administer insulin based on blood sugar changes. Patients need to know what to do once they notice that their blood sugar level is out of its target range.