Insulin pumps are portable devices attached to the body that deliver constant amounts of rapid or short acting insulin via a catheter placed under the skin.
They are seen as a better alternative to insulin injections as they reduce the need for multiple insulin jabs per day and give the user increased ability to control blood glucose levels.
Around 1 in 1,000 people with diabetes wears an insulin pump.
What is an insulin pump?
An insulin pump is a small device (about the same size as a pack of cards) that delivers insulin into the layer of fat that sits just below the skin (subcutaneous tissue).
Because the insulin pump stays connected to the body, it allows the wearer to modify the amount of insulin they take within the press of a few buttons at any time of the day or to program in a higher or lower rate of insulin delivery to occur at a chosen time, which can be when sleeping.
An insulin pump consists of the main pump unit which holds an insulin reservoir (usually 3ml capacity like the cartridges used in an insulin pen).
The reservoir is attached to a long, thin piece of tubing with a needle or cannula at one end.
The tubing and the bit at the end are called the infusion set. Insulin pump therapy is also referred to as continuous subcutaneous insulin infusion therapy.
How common are pumps?
The UK Insulin pump audit of 2013 showed that:
- Around 6% of adults with type 1 diabetes use an insulin pump.
- Around 19% of children with type 1 diabetes use an insulin pump pump.
- Insulin pump therapy is offered to people with type 2 diabetes on a case-by-case basis, when a diabetes consultant with expertise in pump therapy believes strongly that it is the only appropriate treatment for a specific patient. Current research suggests that there is a small proportion of people with type 2 diabetes that have a clinical need for an insulin pump.
Currently, 7 insulin pumps are available in the UK. Read more about eligibility for getting a pump on the NHS.
Its called the Combo System because it combines a blood test meter, bolus calculator and insulin pump.
The Accu-Chek Spirit Insulin Pump allows the administration of bolus without having to look at the pump.
DANA Diabecare R is an insulin pump that also features a remote control as well as blood glucose measuring.
The Animus, part of Lifescan UK is a small insulin pump roughly the same size as a mobile phone.
The Animas Vibe has been designed to ease some of the hassle that can come with using an insulin pump.
The latest incarnation from Medtronic’s Paradigm range is the Veo System. With expert comments from Sue Marshall.
The mylife Omnipod from Ypsomed is an insulin pump with technology that has evolved over the last 18 years.
How does an insulin pump work?
Most insulin pumps (tethered insulin pumps) work by sending insulin, stored in a reservoir within the pump, into your body via an infusion set – a thin plastic tube attached to either a steel needle or a plastic cannula (a very narrow plastic tube). The needle or cannula is inserted into the subcutaneous tissue (the layer of fat tissue just beneath the skin), enabling the insulin to be absorbed gradually into the bloodstream.
Another common type of insulin pump is a patch pump which largely works in the same way except that patch pumps attach directly to the skin and therefore do not require a line of plastic tubing to help deliver the insulin to the cannula.
- Read more on how an insulin pump works
The dose of insulin that is delivered through the day and night can be varied depending on the rate that is pre-set according to your needs (i.e. diet, exercise and blood glucose levels).
Insulin pump history
Insulin pumps are a relatively new piece of diabetes design, invented in the 1970s, although the first insulin pump prototype was developed in 1963.
- 1963: The first prototype of a 'pump' that delivered glucagon as well as insulin was similar to a backpack and was developed by Dr Arnold Kadish.
- 1973: Dean Kamen invented the first wearable infusion pump.
- 1976: AutoSyringe Inc begin to manufacture and market the pumps Dean Kamen invented.
- 1976: Development of continuous subcutaneous insulin infusion begins (insulin pump therapy).
- 1980s: BioStar glucose controlled insulin infusion system used- functioned as an artificial pancreas
- 1990s: Minimed released.
- 2012: Trials of artificial pancreas' begin in the USA.
Currently, companies such as Animas, Ypsomed and Medtronic lead the way in insulin pump technology, which has become smaller over the last 50 years.
The insulin pump has been around for a couple of decades actually. They were very unwieldy to start with as people would have to carry them on a back pack. Insulin pumps are much, much smaller and more sophisticated now.
Very similar idea (to the insulin pen) but you only have one insulin; you don't have to use two because the pump does two things. It gives you what they call the Basal Rate - so it's your base, your Basal rate. You end up having to discover your own needs of a sort of day or night basis. I take silly amounts, very small amounts of insulin. I'm on about half a unit an hour which is like 12 units a day; which is very modest indeed. However, it's just a number for you to get the idea of. Other people would be on different measurements. Nobody actually knows why, it's not actually to do with body mass or anything else.
With your insulin pump, the background is always programmed to go in. That's going through every hour - through the day and night, you wear the pump all the time. Then when you have food, you have to mimic a shot - it's called a Bolus and you basically programme it in and you've got an insulin reservoir which is terribly similar to the cartridge that is linked. The insulin goes through here.
There is a plunger here; it's mechanical instead of manual and that very slowly pushes the insulin out. When you have food, for example if I had sandwiches at lunchtime, I'd probably need about four units of insulin so I'd programme in four units and it'll deliver it through this which is attached to another little canular that drops the insulin into my body. You just use the one insulin and it keeps you going.
The other alternative coming out to this kind of insulin pump is the patch pump. The difference being that instead of the insulin being in this unit, this would still be the control centre. It would be where your blood test results go in and it's where you programme your Basal rate and your Bolus. The insulin will probably be on a patch that is stuck to the body and what it means is no tubing, which really is quite a leap forward.
Tubing can be a little bit in the way sometimes but the downside is that at the moment your infusion set is really quite small. It's about the size of a 10p piece and maybe only 5 millimetres off the body - whereas if you move to a handheld device and a patch (or a pod) then those are bigger. But if you want more freedom, it may be a better choice for you.
How is an insulin pump worn?
Insulin pumps are connected to the body via the infusion set. The small needle or plastic cannula sits under your skin through the day whilst the infusion set is held in place by an adhesive that is similar to the sticky backing of a plaster.
The infusion set can usually be placed in the same sites on the body as are used for injections. The infusion set can usually be left in for two to three days. After this you must insert a new infusion set into a different place on your body. It is important to rotate sites, just as you should do with standard insulin injections.
The pump itself can be safely and discretely attached in lots of different ways, such as to a belt or the waist of trousers, held in pockets or in pouches attached to your thigh or upper arm.
Types of insulin used
Insulin pumps generally use rapid acting insulin, which acts very quickly to minimise the rise in blood sugar after eating. The pump, because it can continually deliver insulin through the day, can therefore use the same rapid insulin to provide a basal (background) dose of insulin.
What is insulin pump therapy?
Insulin pump therapy is the term used to describe the use of insulin pumps in managing blood glucose levels in people with insulin-dependent diabetes.
It is also known as continuous subcutaneous insulin infusion (CSII), which basically explains the function of an insulin pump; to continually infuse insulin into the layer of fat just under the skin (subcutaneous tissue).
Insulin pump therapy has been recognised as being effective in helping people with diabetes, particularly people with type 1 diabetes, to achieve improved HbA1c levels and, in many cases, helping to improve quality of life.
Are insulin pumps better for people with diabetes?
Supporters of insulin pumps believe that they allow diabetics to be more flexible, and eliminate the need for a wearing, daily routine.
A diabetic with an insulin pump does not necessarily have to rise at a certain time to take insulin. When it comes to diet, insulin pumps allows you to be more flexible with that they eat, if they are used in the correct way.