This is the most useful device for self-monitoring of blood glucose (SMBG). Various types and brands of glucometers are available today based on the following two principles:
1. A chemical is present on the test strip which on contact with glucose produces a colour. The meter measures this color intensity and the level of glucose present is expressed in mg/dl.
2. The other type of glucometer measures the electric current in the blood, which depends on the amount of glucose present. When blood is put on the test strip, an enzyme transfers electrons from glucose to a chemical in the test strip and the meter measures the flow of the electrons as current. The amount of current depends on the amount of glucose present and the meter produces the reading in mg/dl.
Accuracy of Glucometers:
Sometimes people are worried about the accuracy of the meter readings. The values are generally quite reliable. There may be a slight inconsequential difference between the laboratory sample and glucometer reading due to the following reasons:
1. A 10-15% difference in readings - because laboratory uses plasma blood while glucometers use whole blood.
2. Meters use capillary blood while laboratory uses venous blood. Capillary blood can give a slightly higher reading than venous blood.
Advantages of glucometers
There are obvious advantages -
It empowers diabetics to take care of themselves without the need to visit doctors and labs regularly.
It promotes well-being of the patient.
It helps to detect and confirm hypoglycemia.
It provides better understanding of medications and also helps to alter medications.
It helps in detecting infections. High blood sugars may be a sign of infection or illness that needs to be treated.
Each glucometer has its own test strips and one must be sure of buying the correct strip for the glucometer. The test strip has a code and before using any test strip the glucometer must be set to the correct code.
These are used to prick the finger to obtain a drop of blood to be placed on a test strip. Each pricking device has its own size of lancet. The lancets are sterile and must not be shared. It can be used for multiple pricks by the same person.