The aim of the insulin pump is to mimic the pancreas. In people without diabetes, the pancreas continuously releases a low level of insulin throughout the day and night (known as basal insulin production), with boosts of insulin released at mealtimes.
The pump is programmed to deliver a continuous background amount of insulin; similar to the basal insulin production of the pancreas and matched to your own requirements. This is called the “basal rate.
The speed of insulin delivery may be programmed to differ at different times of the day and can be altered to match your activity levels.
In addition, a bolus dose of insulin is delivered by pressing buttons on the pump to cover carbohydrates in food eaten or to give a correction if the blood glucose is high.
The pump uses quick-acting insulin (called analogue insulin); such as Novorapid, Humalog, and Apidra.
Because insulin pumps deliver rapid-acting insulin continuously, there is no need to use a long-acting insulin analogue as well. The insulin basal rate can be adjusted at any time. When you eat, you give a bolus dose of insulin through the pump.