TRANSFUSION BLOOD TESTS 1 17 



belongs to the same group as the patient, that is where no interagglutina- 

 tion or hemolysis exists. This is advisable not only so as to get the best 

 results from the^ transfusion, but also in order to avoid any untoward 

 symptoms or intoxications that are associated with the intravascular 

 agglutination or hemolysis (rise of temperature, dyspnea, edema, hemo- 

 globinuria) . The more important of these two factors is not as yet clear. 

 If for a given transfusion a donor belonging to the same class cannot be 

 obtained, it is safer to use a person whose serum is agglutinative toward 

 the patient's cells than one whose cells are agglutinated by the patient's 

 serum. 



The materials necessary for the agglutination and hemolysis 

 Transfusion tests are as follows: 



Tests. (i) Sterile syringes or needles for puncturing the vein; (2) 

 i per cent, sodium citrate solution in 0.85 per cent, salt solu- 

 tion; (3) 0.85 per cent, salt solution; (4) a test-tube rack having 

 two narrow test-tubes (4X1/2 in.) for each donor (numbered); one 

 partly filled with the sodium citrate solution, one empty. 



From each donor i to 2 c.cm. of blood are aspirated from a vein 

 of the elbow; several drops of this blood are allowed to flow into his tube 

 with the sodium citrate solution, the rest is collected in his dry test-tube. 

 This is also done to the recipient, but from him 3 to 4 c.cm. of blood 

 are necessary so as to have sufficient serum for a number of donors (10-15). 



The sodium citrate tubes are centrifugalized and a sediment of the red 

 blood cells obtained; the supernatant fluid is pipetted off and the red cells 

 made up approximately to a 10 per cent, suspension with the normal salt 

 solution. 



The serum tube is also centrifugalized so that clear serum is separated 

 off. The clot should not be disturbed too energetically as it is best to get 

 absolutely clear yellowish serum not blood tinged. 



The following mixtures are then made with each donor's blood, pref- 

 erably within 12-24 hours of the time of collecting the blood: 



(a) 3 parts or units of donor's serum and i part or unit cf recipient's red 

 cell emulsion. 



(b) 3 parts or units of recipient's serum and i part or unit of donor's 

 red cell emulsion. 



Controls: 



(c) 3 parts or units of donor's serum and i part or unit of donor's red 

 cell emulsion. 



(d) 3 parts or units of recipient's serum, i part or unit of recipient's 

 cell emulsion. 



(e) 3 parts of saline, i part of donor's red cells. 

 (/) 3 parts of saline, i part of recipient's red cells. 



These mixtures are made in very small test-tubes (3X3/8 inch). The. 



