Blood can be separated into components like red blood cells, platelets, cryoprecipitate, and frozen plasma which are useful for different medical purposes. Whole blood is rarely used now due to the risk of volume overload. The Coombs test, also known as the antiglobulin test, detects the presence of antibodies and can be performed directly on a patient's red blood cells or indirectly by incubating their serum with donor red blood cells. A positive result in either test indicates the presence of antibodies.

1. Blood components &
Preparation
Dr . T. Arivazhagan
Post Graduate
Department Of Pathology

4. Need for separation

15. •Single whole blood contain
•Red cell
•Platelets
•Cryoprecipitate
•Frozen plasma

20. Uses of whole blood
• Massive transfusion to correct acute hypovolemic state in
trauma and shock
• Now a days rarely used because of volume overload

24. Coombs test
• Also known as antiglobulin test
• To find out the presence of antibodies
• Direct
• Indirect

25. Direct comb’s test
• Used to detect the antibodies or complement proteins
• Blood sample is taken & the RBCs are washed (removing the
patient's own plasma)
• Then incubated with anti-human globulin (also known as "Coombs
reagent").
• Agglutination present – Positive –Presence of Antibodies

26. Indirect coombs test
• Used in prenatal testing of pregnant women
• Serum is extracted from the blood sample
• Serum is incubated with RBCs of known antigenicity
• Anti-human globulin is added
• Agglutination occurs, the indirect Coombs test is positive