2.2 Self-monitoring of blood glucose
Many people with diabetes are encouraged to monitor their blood glucose as it gives them immediate feedback to help them in the day-to-day management of the condition. It can help them to make decisions about lifestyle changes and choices, and to adjust their medication as required (Figure 3). It can therefore be a powerful education and empowerment tool if the person using it has been trained properly in how to do the test correctly and to know what to do with the test results. (Empowerment is an important concept in diabetes management and involves people managing their condition themselves, and making informed choices about their treatment.) However, at the time of writing (2005), there is considerable controversy about whether only people on particular diabetes treatments should be encouraged to do the tests. This is because the cost of the blood testing equipment is relatively high, and in some areas, more money is being spent on the equipment than on the tablets used to treat diabetes. Unfortunately, many people test their blood glucose regularly but do not use the results constructively (often because they have not been shown how to adjust their medication or where to access advice), and therefore the expense of the tests is not justified by an improvement in blood glucose control and a reduction in diabetes complications.
Activity 2 What does Diabetes UK, which represents people with diabetes, say about self-management?
Look at the Diabetes UK website and read the position statement on ‘Glucose Self-monitoring in Diabetes’ (Diabetes UK, 2003).
You will see that Diabetes UK takes the stance that all people with diabetes should be able to test their blood glucose as often as they feel is necessary. However, the National Health Service has a limited budget, and money spent in one area of care means less money for another area. Primary Care Trusts (PCTs), which control budgets for prescribing, may try to limit the number of blood glucose strips being prescribed by the GPs in their locality. Primary Care Trusts are made up of GPs and other health care professionals and are responsible for planning health care services for a local population.
To monitor their blood glucose, people may be given, or may purchase from a pharmacy, a blood glucose meter. This is a device for analysing the glucose content of a small sample of capillary blood, usually obtained from a finger, which is placed on a disposable testing strip and then inserted into the meter. There is a variety of meters available (Figure 4), each using a particular blood glucose-testing strip. The strips are available in containers of 50, and are supplied on prescription from the patient's GP via their local pharmacist.
Activity 3 Finding out about choosing a blood glucose meter
The next time you are out shopping, visit a local pharmacy and look at the range of blood glucose meters available, or if you have access to your local diabetes centre, ask to see their selection of meters. Compare their size, weight, price, the technique for using them, and the blood glucose strips recommended for use with them.
You may find several meters on display in your local pharmacy. They vary in price depending on additional functions. Some are very small and can be carried discreetly in your pocket. However, for people with poor eyesight a meter with a large display may be more suitable.
A person using a blood glucose meter must learn how to use the device correctly (Box 3), especially if they are then using the results to adjust medication. As you saw from Activity 3, there are several types of blood glucose meter available, all with different methods of use, and all requiring a particular brand of blood glucose-testing strip. If you have diabetes, it is important to find a meter that you find easy to use, and has the functions you require to manage your diabetes. For example, some meters have a large memory, which means the results can be downloaded onto a computer. This is useful if you want to look at trends in your blood glucose level over a period of time.
Box 3 Accurate blood glucose monitoring
Some procedures are common to all blood glucose meters, whether you or your carer is doing the test.
Make sure you have the correct strips for the meter you are using. They are all brand-specific, and a meter will not work accurately with the wrong strips.
You must always wash your hands before testing your blood glucose. Any substance on your fingers will contaminate the strip and can give an inaccurate reading.
The meter must be correctly calibrated for the strips in use. This may involve inserting the chip included in the strip packet into the meter each time a new box is opened, or typing in a code number stamped on the package.
Check that the strips have not expired, and that they have been stored at room temperature.
Make sure you have an appropriate device for pricking your fingertip. Needles should not be used. Lancets are available on prescription and should be used once only.
You should prick the side of your finger (Figure 5), avoiding the thumb and forefinger as the skin on these digits is tougher from greater use. Using the side is also less painful than the centre of finger pads. Allow a few seconds for bleeding to start, to allow a sufficient drop of blood to form.
Read and follow the meter instructions carefully!
The sharp lancets that have been used to obtain the blood sample from the finger, or alternative site, must be disposed of carefully. The safe disposal of sharp devices that can transport viruses and infection from one person to another is extremely important. In the diabetes clinic or surgery, sharp devices (lancets and needles) can be safely disposed of in designated sharps boxes or bins (Figure 6a). Unfortunately, you may find that the procedure for disposing of lancets, blood-contaminated strips and tissues, and used needles from insulin devices, is not straightforward outside the hospital or clinic environment. Some local councils provide a sharps disposal service by supplying individuals with sharps boxes and collecting them when they are full. Other areas recommend the use of a ‘safe-clip’, a small device for clipping off the needle and lancet point, which is then retained within the clip (Figure 6b). The remainder of the lancet, needle base, and blood contaminated tissue and strips should be stored in a screw-top container such as an empty bleach bottle (Figure 6c). When the clip and bottle are full, they are placed in the household rubbish.
Can you think of any disadvantages of having a sharps box delivered and collected from an individual's house by the local council refuse department?
The person may be concerned about their privacy. They may not want their neighbours to know they have diabetes. What happens if the person was out when the box is to be collected? Would it be safe to leave the full box on the doorstep?
If a blood glucose meter is used competently, home blood glucose results provide valuable information about the user's daily management of their blood glucose level and this often helps to increase their understanding about the condition. The results are usually recorded in a blood glucose monitoring book or can be downloaded from a computer and printed out as a graph. The record contributes to the assessment carried out during the annual review. As seen in the DCCT and UKPDS studies, long-term complications from a persistently high blood glucose level can occur particularly in small bloodvessels.