TITLE: Crossmatch testing before blood component transfusion
AUTHORS: Grace HJ Chung, Mina Hur, Sang Gyeu Choi, Hyun-Kyung Lee, Hanah Kim, Hee-Won Moon, Yeo-Min Yun

[DESCRIPTION]
<div class = "text-blocks"><div class = "text-block"><div class = "justify" style = "text-align:left"><span style = "font-weight:bold;">1.</span><span style = "font-weight:bold;font-weight:bold;"> </span><span style = "font-weight:bold;">SCOPE AND</span><span style = "font-weight:bold;font-weight:bold;"> </span><span style = "font-weight:bold;">APPLICATION</span></div></div><div class = "text-block">This procedure is applied for compatibility testing of all patients requiring transfusion. Routinely major crossmatch is done in which donor red cells are crossmatched with patient serum/plasma to detect incomplete antibodies in the patient serum/plasma (including indirect antiglobulin phase). Incompatible blood units should not being used for transfusion.</div></div>

[STEPS]
?. [5.	PROCEDURE]
1st saline phase/room temperature immediate spin Saline room temperature is done to detect Major ABO incompatibility and complete (IgM) antibodies/cold antibodies like M, N, S, P, Lewis, Lutheran, etc. This crossmatching method can be done for the issuance of blood in emergencies. A.	Take a test tube. B.	Label with patient’s/donor ID on the tube. C.	Prepare 2-5% red cell suspension of donor red cells.D.	Dispense 2 drops of patient serum/plasma into the labeled tube. E.	Add one drop of donor red cell suspension (from step 3) to the tube containing patient serum/plasma. F.	Spin immediately at 1500g for 15 seconds. G.	Take out the tube gently. H.	Observe for hemolysis and then for agglutination by gentle shaking the tube. I.	Grade and record results, manually. J.	Always continue with anti-human globulin phase, even in emergencies. But in this case, blood units can be released after this phase.
?. [5.	PROCEDURE]
2nd albumin phase/37 OC phase A.	Add 2 drops of bovine albumin and incubate the tube for 30-45 minutes for albumin at 37OC B.	Take out tubes from 37OC. C.	Spin immediately at 1500g for 15 seconds. D.	Take out the tube gently.E.	Observe for hemolysis and then for agglutination by gentle shaking the tube. F.	Grade and record results, manually.
?. [5.	PROCEDURE]
3rd antiglobulin phase (AHG phase)  A.	Wash three times with 0.9% saline using cell washer for 3 mins. B.	Add 2 drops of anti-human globulin.C.	Spin immediately at 1500g for 15 seconds. D.	Take out the tube gently. E.	Observe for hemolysis and then for agglutination by gentle shaking the tube.F.	Grade and record results, manually.
?. [6.	INTERPRETATION OF RESULT]
A. Compatible for transfusion: No Hemolysis / No Agglutination of red cellsB. Incompatible for transfusion: Hemolysis/Agglutination of red cells of any grade (trace, 1+,2+,3+,4+) / Mixed field. NOTE:· All steps should be done immediately· Never use plastic tubes for crossmatch as it adsorbed IgG antibody which can lead to false negative results· Shaking should be done gently· Hemolyzed bag should not be selected for crossmatch· Use clean glasswares· Use all reagents according to the manufactures advice· Never issue blood which is found incompatible at any phase of crossmatch Limitations· The saline/enzyme crossmatch will not:Detect incomplete antibodyEnsure normal donor’s red blood cell survivalDetection of antibodies connected to low level presence of antigens (as with heterozygous expressed blood groups like Fya/Fyb)
?. [7.	DOCUMENTATION]
Enter results in laboratory information system.All records are initialed by technician who performed the test and the technologist who has verified the result.
?. [8.	RESPONSIBILITY]
It is the responsibility of the technician in the clinical laboratory to perform compatibility testing to demonstrate ABO compatibility and report the results. If any unexpected antibody is detected, the medical officer should be informed for further investigation.