Erythrocyte sedimentation rate (ESR)


The rate of erythrocyte sedimentation of the citrate blood is monitored in a specially graduated pipette at certain time intervals. Results are expressed in millimeters per hour.

1. Classical procedure
The content of the tube should be thoroughly mixed before its transfer to a dry, graduated pipette (according to Westergren). The blood is drawn into the pipette up to the mark 0, then it is mounted onto the tube holder taking care it stands in vertical position.
Erythrocyte sedimentation is read after 60 and 120 minutes.
2. Blood sampling by use of vacutainer
The tube is gently stirred 5-10 times, the stopper is removed, and a special sedimentation pipette is inserted directly into the tube. The pipette is filled with blood by capillary force to the mark 0. The tube with the pipette is placed onto a special holder, and erythrocyte sedimentation is read after 60 and 120 minutes.
• The procedure should be performed at room temperature. ESR should not be determined at a temperature below 18 °C because of changes in erythrocyte membrane (such results are clinically useless). Performance of the procedure at a temperature exceeding 18 °C will produce falsely increased results.
• During test performance, the tube holder should not moved and should be protected from direct light.
• False results can be due to inappropriate position of the pipette, inappropriate blood to anticoagulant ratio, effect of sun light, etc.