YES! Finally it’s the end of SIP. But it also means submission for reports and all are coming. Hmm.. Anyway, I was posted to blood bank for the last week. But I am going to post on another test done in the Haematology lab, which I was in for 3 weeks before blood bank lab.
In Haematology lab, it is actually one of the busiest lab. There are constantly a lot of samples sent to the lab to be tested. There are only two types of specimen sent; blood and CSF samples. I am going to share on Erythrocyte sedimentation rate test. In the lab, they make use of the method Sedi-rate P4-Micr System to test for ESR.
Principle Erythrocyte Sedimentation Rate is the rate of sedimentation of red cells in the first 50minutes. This will happen when anticoagulated whole blood is allowed to stand for a period of time, which the red cells will settle from the plasma. The increase in ESR shows indicates some abnormalities in the body.
Sedimentation of the red cells actually occurs in 3 stages. 1) Preliminary stage: In the first few minutes, rouleaux occurs and aggregates forms. 2) The sinking period: This is where the sinking takes place at a constant speed. 3) Last stage: This is where the rate of sedimentation slows which is due to the aggregates settling at the bottom of the tube.
Methods 1. The EDTA blood samples sent to the lab should be mix well. 2. 320µl of blood were pipetted from the EDTA sample to an Aquisel tube containing Trisodic Citrate. 3. The Aquisel tube is mixed well. 4. The pipette is introduced into the Aquisel tube. The pipette is pushed downwards until the blood fills the whole pipette. The blood level should be at “0” on the markings of the pipette. 5. The timer is set to 50minutes and time starts. 6. A small LIS generated sticker is to be stick over the Aquisel tube. 7. Another small LIS generated sticker is to be pasted on the ESR record book. (For record purposes) 8. A “miscellaneous testing” is stamped on the request form and initiated. 9. After 50minutes exactly, the values on the pipette is read and results are taken down in the ESR record book and the request form, which is also to be signed for traceability. 10. The results are to be entered and verified manually in the LIS system.
Reference value
Neonates 1 to 2 days old : 0 to 4mm/50minutes Neonates 3 days to 1 month old : 0 to 10mm/50minutes Paediatrics 2months to 12years old :0 to 10mm/50minutes Adults more than 12years old :0 to 10mm/50minutes
IF theESR values are higherthan the reference value, it can means: Ø Increase in fibrinogen and/or globulin Ø Decrease in albumin concentration Ø Decease in cell pack volume Ø Tuberculosis, Rheumatic fever, kidney disorder, systemic Lupus Erythematosus (SLE) Ø Anemia
*Things to take note The specimen tubes should be checked, there should not be any blood clots or platelet clumps, if there are clumps present, the results would not be vaild. The test should also be done in 4 hrs after the blood collection as the red cells would become spherical after that and it affects the results. The ESR pipette should be left standing on a rack upright, if there is any tilting, it accelerates the ESR. If the blood is lysed, the results will also have error.
