A blood glucose monitor works by measuring the amount of glucose present in a blood sample, typically obtained from a finger prick. While traditional blood glucose monitors analyze a direct blood sample, Continuous Glucose Monitoring Systems (CGMS) use a different approach.
Here's a breakdown of how both types function:
Traditional Blood Glucose Monitors
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Sample Collection: A small drop of blood is obtained, usually by pricking a fingertip with a lancet.
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Application to Test Strip: The blood sample is applied to a disposable test strip, which contains specific chemicals.
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Chemical Reaction: The glucose in the blood reacts with the chemicals on the strip, often involving an enzyme like glucose oxidase. This reaction produces an electrical current.
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Measurement and Display: The monitor measures the strength of the electrical current. The current's strength is directly proportional to the glucose concentration in the blood. The monitor then displays the glucose level in a numerical value (e.g., mg/dL or mmol/L).
Continuous Glucose Monitoring Systems (CGMS)
CGMS offer a more continuous reading of glucose levels. These devices have three key components: a sensor, a transmitter, and a receiver.
- Sensor: According to the provided reference, the sensor is inserted under the skin to measure glucose levels in the interstitial fluid, which surrounds the cells below your skin.
- Transmitter: The transmitter wirelessly sends the glucose data from the sensor to the receiver.
- Receiver: The receiver displays the glucose levels, providing a continuous stream of data that helps users track glucose trends.
The primary difference between the two is that traditional monitors measure glucose in blood, while CGMS measure glucose in interstitial fluid.
Summary Table
| Feature | Traditional Blood Glucose Monitor | Continuous Glucose Monitoring System (CGMS) |
|---|---|---|
| Sample Source | Blood | Interstitial Fluid |
| Measurement Method | Chemical reaction and electrical current | Sensor measuring glucose in fluid |
| Frequency | Intermittent (as needed) | Continuous |
| Components | Monitor, test strips, lancets | Sensor, transmitter, receiver |
