INSULIN PUMP THERAPY
Continuous Subcutaneous Insulin Infusion
Insulin pump therapy or CSII is a treatment that some people with Type1 diabetes may find
beneficial in terms of improving overall glycaemic control and quality of life.
Insulin pump therapy was first introduced in the 1970s but recent advances in the way
insulin pumps work have renewed interest in this method of administering insulin.
Insulin pumps cost approximately £3000 to buy and attract an annual cost of approximately
£1500 for the consumables required.
How do insulin pumps work?
Most insulin regimes are based on a long-acting insulin combined with a smaller amount of
faster-acting insulin, normally injected either twice or four times a day.
Pumps work by delivering a variable dose of fast-acting insulin continually throughout the
day and night, at a rate that is pre-set according to the patient’s requirements. This is
referred to as the basal rate.
Pump users then calculate bolus doses of insulin that are also administered via the pump.
Bolus doses of insulin are given if the patient is planning to eat more than 5gm of
carbohydrate and it is essential that all patients who use pumps have a good
understanding of ‘carbohydrate-counting’ so they can calculate the dose of insulin required
As a general guide patients are advised to administer 1 unit of insulin per 10 gm of
Pumps are able to deliver very small doses of insulin e.g. 0.1 unit if required. Patients are
taught how to administer correction doses of insulin if blood glucose is raised, based on
the formula that 1 unit of insulin will drop the blood glucose by approximately 2.5mmols/l.
The pump is about the size of a pager and is worn 24 hours a day. Patients are advised
not to be disconnected from the pump for more than one hour. The pump runs on batteries
and has many safety features that will alert the patient to the fact that the pump may be
malfunctioning. Patients should always carry with them their insulin pen in case the pump
As the pump delivers only fast-acting insulin Diabetic Ketoacidosis (DKA) can develop very
quickly if there is a malfunction and insulin does not reach the patient. Patients are fully
educated as to how to avoid DKA.
The pump can be safely and discreetly attached in a variety of ways e.g. to a belt or to the
waist of trousers. It can also be placed in a small bag that is attached to the arm or leg, if
the insulin is being administered via these sites.
Running from the pump is an infusion set, which is inserted under the skin via either a
small needle or plastic cannula. This cannula needs to be changed every three days and
reinserted into a different site.
There are different types of pumps, but most can be safely worn during exercise. However
the pump can be disconnected for a short time if the patient thinks it may become damaged
e.g. whilst doing contact sports or swimming (some of the newer pumps are waterproof) or
during periods of intimacy.
When disconnecting the pump, the needle or cannula stays in the body. Caps are then
placed over the exposed end of both the needle or cannula and the tubing to maintain
Who can use Pump Therapy?
Pump therapy is not suitable for all people with Type 1 diabetes. A thorough assessment
of the patient’s suitability for pump therapy needs to be carried out by the diabetes team
and in order to be considered the patient must:
Have a good knowledge and understanding of diabetes.
Have a good understanding of carbohydrate counting before pump therapy commences.
Be well motivated and willing to take control of their diabetes.
Be prepared to test blood glucose levels at least 4 times a day and be confident in acting
on those results.
Be willing to learn and attend for education sessions as deemed appropriate.
Have a sound understanding of how insulin, exercise and food intake affect blood glucose
To ensure that everyone using a pump learns to do so safely and gains the greatest benefit
from the facilities of the pump, healthcare professionals undertaking pump therapy, with
their patients, need to have been adequately trained. This is a specialised area and as
such should only be undertaken by diabetes teams who possess these specialised skills.
In July 2008 the National Institute for Clinical Excellence (NICE) issued guidance on insulin
pump use in the NHS. They have recommended that insulin pump therapy be available as
a treatment option for people with Type 1 diabetes in cases where:
Multiple dose insulin therapy (including insulin glargine) has failed
The person is willing to use insulin pump therapy effectively
Multiple injection therapy is considered to have failed when a person is unable to maintain
their blood glucose levels without disabling hypoglycaemia occurring or has failed to
achieve a reasonable HbA1c target. This failure must be despite a high level of self care of
Failure to achieve targets because of poor self care of diabetes is not an indication for
pump therapy, indeed starting such patients on a pump is a recipe for disaster.
For full NICE guidance on insulin pumps please see the NICE website
At Trafford NHS Healthcare Trust 30 people are currently using pump therapy (July 2008).
For further detailed information see:
Medtronic Minimed www.minimed.com
Roche Diagnostics www.roche-diagnostics.com or www.accu-chek.co.uk
Author: -Diabetes Multidisciplinary Team. Version No 1.Issue Date: -July 2004.Review Date: July 2006
Author: -Diabetes Multidisciplinary Team. Version No.2.Issue Date: -Jan. 2009.Review Date: Jan. 2011