Wintrobe Tube

Method of Westergren
For the Westergren method, 2 ml of venous blood must be drawn into a tube containing.5 ml of sodium citrate. It shouldn’t be kept for more than two hours at room temperature or six hours at four degrees Celsius. A Westergren-Katz tube is filled with blood up to the 200 mm mark. The tube is kept rigidly vertical in a rack at room temperature for an hour, after which the distance between the upper limit of the red cell sediment and the lowest point of the surface meniscus is measured. The ESR is the erythrocyte fallout measured in millimetres over a single hour.

Wintrobe technique

The Wintrobe procedure is carried out identically, however the Wintrobe tube is only 100 mm long and has a smaller diameter than the Westergren tube. After one hour, the rate of red blood cell loss in millimetres is measured in the tube using EDTA anticoagulated blood that hasn’t been given any additional diluent. This method is less sensitive than the Westergren method since the greatest possible aberrant value is smaller due to the shorter column. This approach is more useful for demonstrations, though.

Healthy males typically have values of around 15mm/hr; healthy females typically have values of around 20mm. Both genders’ values rise modestly as they get older.