Calibrating Glucose Monitors: Steps To Accurate Readings

Glucose monitors are small devices worn on the body that consistently monitor glucose levels, reducing or eliminating the need for finger sticks. Calibration is a process that ensures the monitor's sensor provides accurate glucose readings. Calibration can be done by the manufacturer, the person wearing the monitor, or both. To calibrate a glucose monitor, you will need a glucose monitor and testing supplies on hand. It is important to ensure that your testing supplies are stored at a cool temperature and that the test strips have not expired before use. Wash your hands using soap, water, or alcohol to prevent anything from causing an inaccurate reading. You should only check blood glucose on your fingertips. After checking your blood glucose with your meter, enter this value into your monitor receiver, insulin pump, or phone app.

Wash hands with soap, water, or alcohol to prevent inaccurate readings

Calibrating a continuous glucose monitor (CGM) is important to ensure you are getting accurate data from the device. CGMs are small devices worn on the body that consistently monitor glucose levels, reducing or eliminating the need for finger sticks.

To calibrate a CGM, you will need a glucose monitor and testing supplies on hand. It is important to ensure that your testing supplies are stored at a cool temperature and that the test strips have not expired. Before you begin, wash your hands using soap and water, or alcohol, to prevent anything from causing an inaccurate reading.

Washing your hands with soap and water, or using an alcohol-based hand sanitiser, is an important step in preventing inaccurate glucose readings. This is because glucose meters measure blood glucose by taking a drop of blood from the fingertip, and any residue on your fingers can affect the reading. For example, if you have handled fruit, invisible pieces of fruit sugar may remain on your hands and cause your blood sugar level to appear higher than it is. Similarly, if you have consumed sugary drinks, residue on your fingers can cause a spurious result. Therefore, it is always best to wash your hands thoroughly with soap and water before testing your blood sugar.

In a clinical study, participants who washed their hands with water before testing had the same blood sugar readings as before they had handled fruit. When they peeled fruit and then tested their blood sugar without washing their hands, their levels were often twice as high due to the residual sugar on their skin. Even swabbing the finger with alcohol multiple times did not produce correct results.

Alcohol-based hand sanitisers have become a popular alternative to soap and water, especially when the latter is not available. They are effective for reducing infection rates and are recommended as a component of hand hygiene in clinical settings. However, depending on the surface area, hand sanitizers may not be adequate for cleaning the skin prior to glucose meter testing. This is because alcohol may lead to sample contamination, which can result in the denaturation of the enzyme used in measurement methods. Therefore, when using alcohol to clean your hands before a glucose test, it is important to ensure that the disinfectant has completely evaporated before taking the measurement.

Check blood glucose on fingertips only

How to Calibrate a Glucose Monitor

Checking your blood glucose levels regularly is vital for managing diabetes. If you use a continuous glucose monitor (CGM), you can check your blood glucose on your fingertips only. CGMs are small devices worn on your body that consistently monitor glucose levels. They reduce or eliminate the need for checking finger sticks.

If you are calibrating your CGM yourself, you will need to have a glucose monitor and testing supplies on hand. It is important to ensure that your testing supplies are stored at a cool temperature and that the test strips have not expired before use.

Before checking your blood glucose levels, always wash your hands with soap and water for a more accurate result. Do not use hand sanitiser before doing finger sticks. After washing your hands, check your blood glucose with your meter, then enter this value into your CGM receiver, insulin pump, or phone app as soon as possible.

While finger sticks can be painful and time-consuming, they are still extremely important for those with diabetes to keep track of their blood sugar readings. If you are tired of the pain of finger-sticking, alternate site testing is an option, such as testing on the palm of your hand or your thumb. However, these sites may not always provide easy access to get enough blood for a test strip.

It is important to note that there is a timing difference in blood glucose levels between the forearm and fingertip. A blood glucose result taken at the fingertip will not reach the forearm capillaries for 20 to 30 minutes. Therefore, if you are concerned about the timing of testing or suspect that your blood sugar level is low, it is best to stick with finger testing.

Input blood glucose value into CGM receiver, insulin pump, or phone app

To input your blood glucose value into a CGM receiver, insulin pump, or phone app, you will need a glucose monitor and testing supplies. Make sure your testing supplies are stored at a cool temperature and that your test strips have not expired. Wash your hands with soap, water, or alcohol to prevent anything from causing an inaccurate reading.

Check your blood glucose level with the meter, and then enter this value into your CGM receiver, insulin pump, or phone app as soon as possible. Remember, your glucose levels are constantly changing, so you want to calibrate with a recent blood glucose number.

The best times to calibrate are when your blood glucose levels are stable, or when the trend arrow is lying flat. This will usually be first thing in the morning or before meals. Avoid calibrating when your blood glucose levels are changing quickly, or when the trend arrows point up or down. This may occur after eating, taking insulin, or exercising.

Store testing supplies at a cool temperature

Calibrating a glucose monitor is a process that ensures the device provides accurate glucose readings. To calibrate your glucose monitor, you will need a glucose monitor and testing supplies.

It is important to store your testing supplies at a cool temperature to ensure accurate readings. Exposure to extreme hot or cold temperatures may affect the accuracy of your readings. Aim to keep your testing supplies between 35 and 86 degrees Fahrenheit. Store your supplies in a dry, room-temperature location in your home. Avoid storing them in areas that are not temperature-controlled, such as an unheated garage or basement.

Additionally, do not keep your testing supplies in areas that experience temperature changes, such as a bathroom cupboard or a kitchen counter exposed to heat from an oven. Check your testing supplies for any potential damage, such as leaking or torn packaging, before use. By storing your testing supplies properly, you can help ensure accurate and reliable results.

Use test strips of the same brand as your meter

Using test strips of the same brand as your meter is one of the most important factors in ensuring the accuracy of your glucose readings. While it may be tempting to opt for third-party products, these are not always compatible with branded meters and can cause inaccurate or error readings. This is because different manufacturers have their own unique processes for developing their test strips.

To ensure the best results, it is also important to check that your test strips are not past their expiration date. Test strips also need to be stored correctly—extreme heat or cold conditions can affect their performance. Therefore, it is not recommended to store your testing supplies in your car. High altitude can also impact the accuracy of readings, so be sure to follow the manufacturer's storage instructions carefully.

In addition to using the correct test strips, there are several other steps you can take to ensure accurate glucose readings. Firstly, always wash your hands before testing your blood sugar and clean the area around your finger. This will prevent dirt, food, grease, or any other kind of residue from affecting your reading. It is also important to ensure your testing site is dry before taking a reading, as moisture can dilute the blood sample.

Another factor that can impact the accuracy of your readings is the amount of blood on the test strip. If there is insufficient blood, this can cause an error or false reading. You can adjust the settings on your lancet to ensure you are drawing enough blood. It is also important to fully insert the test strip into your meter.

By following these steps and using test strips of the same brand as your meter, you can help ensure the accuracy and reliability of your glucose readings.

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