Insulin pump - Medical Experts

Insulin pumps are small devices worn on the body that provide a continuous supply of insulin to people with diabetes. They mimic the way a healthy pancreas works, which normally provides the right amount of insulin on an ongoing basis.

Instead of injecting insulin several times a day, people with diabetes wear the pump directly on their body. The device continuously delivers small amounts of insulin and can also be controlled at the touch of a button to deliver insulin at mealtimes. This ensures that the insulin is delivered to where the body needs it.

An insulin pump continuously delivers insulin into the body. The insulin travels from the pump via a thin tube (catheter) to a fine cannula, which is inserted into the subcutaneous fatty tissue at the injection site. From there, the insulin is absorbed into the bloodstream.

Insulin is delivered in two ways: via the so-called basal rate, the pump delivers a small, constant amount of insulin round the clock to cover the body’s basic needs. At mealtimes, the user also administers a bolus to cover the carbohydrates consumed.

This allows individual insulin requirements to be controlled very precisely – it also helps to better manage specific situations such as the dawn phenomenon, the morning rise in blood sugar. The aim is to maintain stable blood sugar levels throughout the day.

When it comes to the different types of insulin pumps, there are essentially two main designs.

Traditional tubing pumps are connected to the infusion set and the cannula via a flexible tube. The pump itself is worn, for example, on a belt or in a trouser pocket.

Tubeless models, known as patch pumps, are, by contrast, attached directly to the skin as a small plaster. With these skin-adhered pumps, the mechanism sits directly on the injection site, so there is no need for a separate tubing. They are usually controlled via a separate device or a Personal Diabetes Manager.

The type of insulin pump that is suitable depends on personal needs and everyday life. The insulin pumps currently available cover both designs.

An insulin pump is particularly suitable for people with type 1 diabetes whose blood glucose levels are difficult to control using conventional intensive insulin therapy (ICT). A pump may also be beneficial in cases of frequent hypoglycaemia or highly fluctuating blood glucose levels.

The treating diabetologist will decide whether an insulin pump is suitable in each individual case. Patients who wish to use an insulin pump in particular should receive thorough training beforehand – for example, in how to use the device and in recognising the signs of impending ketoacidosis should the insulin supply ever be interrupted.

Insulin pumps can be used by children as well as adults.

Costs and cost coverage

An insulin pump is prescribed as a medical aid where there is a corresponding medical need. Where this is the case, the costs are usually covered by health insurance.

The statutory health insurance provider assesses on a case-by-case basis whether the criteria are met. In addition to the pump itself, ongoing consumables such as catheters, infusion sets and cannulas are usually reimbursed.

In everyday life, an insulin pump is less of a hindrance than many initially fear. As it automatically delivers small amounts of insulin, there is no need for daily injections – the right amount of insulin is available at the touch of a button.

Many pumps are waterproof or can be disconnected for short periods, so showering or bathing is no problem. This means the pump can be worn comfortably whilst showering, exercising or sleeping. When exercising, the basal rate can be adjusted as needed to prevent hypoglycaemia.

It is important to change the catheter regularly and to check the injection site – for example, in case the cannula becomes blocked. This ensures that insulin delivery remains reliable and makes it easy to plan daily life with diabetes.

Modern insulin pumps can be paired with a continuous glucose monitoring (CGM) system. A small sensor in the subcutaneous tissue continuously measures blood glucose levels and transmits the readings to the pump or a separate device.

In such linked systems, insulin delivery can be adjusted automatically: if hypoglycaemia is imminent, the pump reduces the insulin flow. This close integration of the sensor and pump makes it much easier to manage blood glucose levels and increases safety in everyday life.

Like any form of treatment, the insulin pump has both advantages and disadvantages.

The advantages include highly accurate, continuous insulin delivery, greater flexibility with meals and exercise, and often better blood glucose control. There is no longer the daily hassle of injections.

The disadvantages of an insulin pump include the fact that the device must be worn on the body round the clock, and that components such as catheters or cannulas can cause discomfort or become blocked. If insulin delivery stops unnoticed, blood glucose levels can rise rapidly. Whether the advantages outweigh the disadvantages always depends on the individual’s personal situation.