1. Performing a Erythrocyte Sedimentation Rate

2. Erythrocyte Sedimentation Rate
The erythrocyte sedimentation rate (ESR or sed rate) is a test measuring the rate at which erythrocytes (RBCs) settle.
This test is used to diagnose inflammation and inflammatory disorders.
The test is also used to monitor the treatment of an inflammatory disorder.
A sample of anticoagulated blood, commonly EDTA, is placed into a tube and the blood is allowed to settle.
After a specific amount of time, per the procedure used, the amount of RBC settling is measured.

3. Erythrocyte Sedimentation Rate
Performing an ESR
To perform a manual ESR test you need a
calibrated tube filled with anticoagulated blood.
The RBCs will settle toward the bottom leaving
plasma at the top area.
The sample is left for a specified amount of time.
At the end of the time period, you measure the distance
from where the sample started to the settled RBCs.
Most healthy people have slow ESR rates.
In patients with specific inflammatory disorders,
the rate of sedimentation is faster.
Sometimes the faster the settling the worse the
severity of the disease.

4. Erythrocyte Sedimentation Rate
Factors effecting an ESR include…..
The plasma’s properties  if rouleaux is present
Rouleaux is when the RBCs form stacks
Rouleaux increases the mass of the RBCs and
increases the rate of sedimentation.
The RBC’s properties
Large RBCs (macrocytes) settle faster than small
cells (microcytes).
Irregular shaped cells cannot settle as fast and
result in a slower rate of settling.
Spherocytes (small compact cells) fall at a
slower rate.
The rate of settling is also affected by the
number of RBCs present

5. Erythrocyte Sedimentation Rate
Factors effecting an ESR include…..
Way the procedure is carried out
The settling tube must be kept upright, straight,
and standardized
Counter should be level
Temperature should be kept constant
Blood sample should be used within 2 hours of
collection and well mixed
Test must be timed correctly
There are several methods used for performing an ESR.
Manual methods
Automated methods

6. Reference Ranges Each method has its own reference values.
Reference values differ slightly depending on gender and age.
Most range from 0-20 mm/hr