erythrocyte sedimentation rate
- Introduction
- Method
- Principle
- Normal range
- Specimen
- Requirement
- Procedure
- Precaution
- Clinical significance
Table of Contents
Introduction
- erythrocyte sedimentation rate (ESR) is a blood test that that can show if you have inflammation in your body.
Method of erythrocyte sedimentation rate
- it is two method .
- Westergren’s method and Wintrobe method
1. westergren’s method
Principle of erythrocyte sedimentation rate
When whole blood mix with anticoagulant and it is allow to stand on a veritcal tube,the red cell is settled down due to gravity.
Normal range of erythrocyte sedimentation rate
- Male 0 to 15 mm after one hour
- Female 0 to 20 mm after one hour
Specimen
- Small tube (100 x 10 mm) with 2.5 ml mark is used for blood collection (If the tube is not graduated, pipette out 2.5 ml of 3.8% sodium citrate in the tube and after marking the level of fluid, remove 2.0 ml of the solution leaving 0.5 ml of the anticoagulant in the tube).
- The tubes with 0.5 ml of 3.8% sodium citrate should be kept ready before blood collection.
- Patient should be fasting for 12 to 16 hours. Collect blood by vein puncture and add in the tube up to the mark and mix carefully.
Requirement
1 Westergren’s ESR tube
2 Stand for holding the tube
3 Timer or watch
Procedure
1 Fill the Westergren tube exactly upto zero mark by means of a rubber bulb (avoid air bubbles).
2 Place the tube upright in the stand. It should fit evenly into the groove of the stand.
3 Note the time. Allow the tube to stand for exactly one hour.
4 Exactly after one hour, note the level to which the red cell column has fallen.
5 Report the result in terms of mm/after 1 hour.
Precaution
Wash the tubes as early as possible, under running tap water. Rinse in de-ionized water and dry in the incubator between 40-50°C.
2. Wintrobe method
sample
- Fresh fasting EDTA anticoagulated and undiluted blood. (It is necessary to draw at least 2 to 3 ml of blood for both CBC and ESR determinations).
Requirement
1 Wintrobe tube
2 Wintrobe tube stand
3 Pasteur pipette or 2 ml syringe with needle
4 Timer or watch
Procedure
1 Mix the blood carefully
2 Fill the Wintrobe tube to the zero mark by using a Pasteur pipette or by using a syringe.
3 Place the tube in exact vertical position in the stand. Set timer for one hour.
4 At the end of one hour note the level of erythrocyte column in terms of mm after 1 hour.
Precautions
1 Wash the tubes under running tap water by introducing a thick wire in the tube repeatedly to remove the packed cells completely. Afterwards dry the tubes in the incubator (40-50°C).
2 In the case of infants and if blood quantity is insufficient use ‘Landau’ method
Note
This method provides both ESR and PCV values. After noting the ESR value, the same tube can be centrifuged for PCV.
