Specifications.

1. Material: Most disposable ESR tubes are made of plastic, which reduces the risk of breakage and potential exposure to bloodborne pathogens.
2. Graduations: The tubes are graduated (usually in millimeters) to allow for the direct reading of the erythrocyte sedimentation rate.
3. Volume: Typically, the tubes are designed to hold 2.0 mL of citrated blood.
4. Length: The standard length for Westergren tubes is approximately 300 mm, in accordance with international recommendations.
5. Closure: Some disposable ESR tubes come with a cap or stopper, making them suitable for mixing blood and citrate without spillage.
6. Compatibility: They’re designed to be compatible with standard ESR racks and automated ESR analyzers.
7. Usage: The procedure begins by mixing venous blood with anticoagulant (often sodium citrate) in the recommended proportion. This mixture is then filled into the Westergren tube, which is placed vertically in a rack. After one hour, the distance (in millimeters) that the red blood cells have sedimented is the ESR, which is read directly off the tube’s graduations.
8. Safety: Disposable tubes reduce the risk of cross-contamination. After a single use, they’re disposed of safely, in accordance with biohazard waste protocols.
9. Advantages: Apart from the safety aspect, disposable tubes ensure consistency in the testing process since they’re uniformly manufactured. They also save time, as there’s no need for washing, disinfecting, or checking for imperfections as with reusable glass tubes.