290 AGGLUTININS 



TESTS BEFORE TRANSFUSION FOR ISOHEMAGGLUTININS 

 AND ISOHEMOLYSINS 



1. Two or three c.c. of blood are obtained from each donor from a 

 vein at the elbow and 0.5 c.c. is placed at once in a centrifuge tube con- 

 taining 5 c.c. of a 1 per cent, sodium citrate in normal salt solution. 

 The remainder is placed in a small, dry test-tube until coagulation has 

 occurred and the serum has separated. 



2. From the recipient, 3 to 4 c.c. of blood are necessary; 0.5 c.c. is 

 placed in sodium citrate solution, and the remainder is allowed to coagu- 

 late and the serum collected. 



3. The sodium citrate tubes are centrifuged; the supernatant fluid 

 is pipeted off, and the cells are washed again with normal salt solution. 

 After the final washing enough normal salt solution is added to the sedi- 

 ment of cells to bring the total volume up to 5 c.c. 



4. The serum tubes are also centrifuged, so that clear serums are 

 obtained. These should preferably be free from hemoglobin stain. 



5. The following mixtures should be set up within twenty-four hours 

 of the time of collecting blood, in order that native complements may 

 not have undergone deterioration. Measurement may be made ac- 

 cording to a drop from an ordinary 1 c.c. graduated pipet held vertically. 

 Small sterile test-tubes (8 by 1 cm.) are to be used. 



Tube 1 : 4 drops of donor's serum + 1 drop of recipient's red-cell 

 emulsion. 



Tube 2 : 4 drops of recipient's serum + 1 drop of donor's red-cell 

 emulsion. 



Tube 3: Control: 4 drops of donor's serum + 1 drop of donor's 

 red-cell emulsion. Should show no agglutination and no hem- 

 olysis. 



Tube 4: Control: 4 drops of recipient's serum + 1 drop of re- 

 cipient's red-cell emulsion. Should show no agglutination or 

 hemolysis. 



Tube 5: Control: 1 drop of donor's red-cell emulsion + 4 drops 

 of normal salt solution. This serves as a control on the toxicity 

 of the corpuscles and isotonicity of the salt solution. 



Tube 6: Control: 1 drop of recipient's red-cell emulsion + 4 



drops of saline solution. 



One cubic centimeter of salt solution is added to each tube and the 

 tubes are gently shaken and placed in the incubator for two hours. 

 They are to be inspected every half hour. Agglutination is recognized 



