Insulin Delivery Method: Insulin Pumps

Before deciding on an insulin pump, weigh the pros and cons carefully

Recent technological advances have led to smaller, more comfortable external insulin pumps that are easier to use, making them an ideal option for carefully selected patients. About the size of a pager, these computerized devices are usually worn discreetly on a belt or placed in a pocket. Insulin passes from a reservoir within the pump through a thin, flexible tube to a fine needle (or soft catheter) inserted beneath the skin and taped in place. Known as continuous subcutaneous insulin infusion, or CSII, this method continuously delivers measured amounts of insulin (basal dose) over a 24-hour period; in addition, the pump wearer simply presses a button on the pump to release a supplemental (bolus) dose before each meal. People adjust the size and timing of these bolus doses according to when and how much they wish to eat. The use of external insulin pumps has been almost entirely limited to patients with Type 1 diabetes.

Before deciding on an external insulin pump, weigh the pros and cons carefully.

• The basal rate of insulin can be adjusted, for example, infusing less insulin as you sleep to prevent hypoglycemia during the night. The pump also makes it easier to adjust mealtime bolus doses. Often, therefore, better blood glucose control may be achieved than with standard self-injections. In addition, the pump offers greater convenience and a more flexible meal schedule, which may particularly benefit people who are very active or who travel frequently.
• Most people find the pump quite comfortable, even during vigorous activity. (The needle is painless once inserted.) The pump unit is waterproof or has a waterproof pouch, so it can be worn during bathing. It can also be removed for brief periods, such as during exercise or for special occasions.
• Pump therapy is appropriate only for people who are highly committed and responsible. Because the pump uses only rapid-acting insulin, any sort of malfunction (such as a detached needle, blocked tubing or battery failure) causes a rapid drop in blood insulin levels; dangerously high blood glucose levels can develop within hours. Although pumps have built-in alarms to alert users to such problems, they are not foolproof. For this reason, pump users must frequently monitor blood glucose levels throughout the day and diligently keep their pump in working order. This includes making sure the basal rate is set correctly, checking the tubing for blocks or kinks, keeping the insulin reservoir full and changing the infusion needle every two to three days to prevent infection.
• Pump therapy is expensive and may not be a viable option unless your insurance carrier covers most or all costs.

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