Diabetes self-management: the correct way to use a home blood glucose meter

Author: Wang Xuejing, Chief Physician of Civil Aviation General Hospital

Reviewer: Zhang Yu, researcher at Chinese Center for Disease Control and Prevention

For diabetic patients, self-monitoring of blood sugar has become a part of daily life. However, many people are concerned about how to use home blood glucose meters correctly, how to calibrate them, and how to properly arrange the relationship between self-monitoring and hospital testing to ensure the accuracy of measurement results.

The accuracy and stability of home blood glucose meters are crucial. First of all, when purchasing a blood glucose meter, you should choose a reputable brand and read the instructions carefully before using it for the first time to understand the working principle and operation steps of the blood glucose meter. New blood glucose meters have been calibrated at the factory, but after long-term use, the measurement results may deviate due to problems such as aging of electronic components or blockage of internal pipes. For this reason, it is recommended that users send the blood glucose meter to the sales point or the manufacturer's service center for calibration at regular intervals. Usually, the service point will be equipped with three concentrations of calibration fluid, high, medium and low. By testing these standard samples, it can be determined whether the blood glucose meter is still accurate. If the test results show a large deviation, calibration or replacement of a new instrument is required. In order to ensure the accuracy of the blood glucose meter, it is recommended to calibrate it at least once a year, and if conditions permit, it can be calibrated every six months.

In the actual operation, patients should pay attention to the following points to ensure the reliability of the measurement results. First, before collecting blood samples, patients should be in a quiet state and avoid strenuous exercise or emotional fluctuations, because these factors may cause a temporary increase in blood sugar levels, thereby affecting the measurement results. Secondly, the preferred site for collecting blood samples is the inner side of the tip of the ring finger, because the pain sensitivity here is low and it is easy to compress and stop bleeding. Before collection, the blood collection site should be disinfected with iodine or alcohol cotton balls, and the disinfection range is about 1-2 cm. It should be noted that the first drop of blood collected should be discarded because it may be mixed with disinfectants or tissue fluid, which will affect the measurement results. The correct approach is to wait for disinfection and dry, pierce the skin with a spring needle of appropriate depth, and collect the second drop of blood for testing. In addition, excessive squeezing of the fingers should be avoided when collecting blood to prevent tissue fluid from mixing into the blood, resulting in low measurement results.

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In addition to the above operational details, the impact of external factors on blood sugar measurement should also be considered. For example, taking vitamin C or glutathione may interfere with the working principle of the blood glucose meter and cause deviations in the measurement results. In addition, factors such as the oxygen content in the environment and the number of red blood cells in the blood may also affect the final measurement results.

Although home blood glucose meters are convenient, they cannot completely replace professional testing in hospitals. Diabetic patients still need to go to the hospital regularly for comprehensive examinations, including the measurement of blood sugar, glycated hemoglobin, and glycated albumin. This is because these tests can more comprehensively reflect the recent blood sugar control situation. For example, glycated hemoglobin reflects the average blood sugar level in the past 2-3 months, while glycated albumin reflects the blood sugar status in the past 2-3 weeks. By comparing these two indicators, doctors can more accurately evaluate the effect of blood sugar control, whether the medication is used regularly, etc.

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