310 APPLIED IMMUNOLOGY 



others have devised paraffin-lined glass tubes for the passage 

 of blood from the vessel of the donor to that of the recipient. 



Crile was one of the first to employ the direct method 

 of transfusion extensively, and he unites the radial artery 

 of the donor to a superficial vein in the arm of the recipient 

 by means of a special clamp {Keen's Surgery, Vol. V, p. 616). 

 Numerous other instruments have been recommended for this 

 purpose, among others, those of Landon {Jour, A, M. A,, 

 Aug. 16, 1913) and McGrath {Jour. A. M, A,, Jan. 3, 

 1914). 



The difficulties of blood-vessel anastomosis have led 

 many surgeons to devise various forms of apparatus for 

 removing blood from the donor, preventing it from clotting, 

 and subsequently introducing it into the vein of the recipient. 

 An advantage of indirect transfusion is that the amount 

 of blood utilized can be exactly measured. Kimpton and 

 Brown {Jour, A, M, A., July 12, 1913) have devised a 

 glass cylinder lined with paraffin, into which they withdraw 

 the blood, which is considerably delayed in clotting by the 

 paraffin. 



Probably the simplest method of indirect transfusion 

 is that recommended by Dorrance {Penna, Med, Jour., 

 Sept., 1914). The blood is removed from a vein of the 

 donor by means of a 50 c.c. all-glass syringe, in which has 

 been previously placed 10 c.c. of a 10 per cent, solution of 

 sodium citrate to prevent clotting. After withdrawal of a 

 syringeful of blood, the syringe is detached, the needle re- 

 maining in the vein of the donor in case more blood is re- 

 quired, the lumen being closed with a stilette. The blood 

 mixed with sodium citrate solution is then injected through 

 a needle similarly introduced into a vein of the recipient. 

 Dorrance states that with experience this operation can be 



