k 



THE TOTAL QUANTITY AND DISTRIBUTION OF THE BLOOD 231 



be more quickly restored than if the saline alone is used. For the same reason it 

 has recently been advocated to raise the viscosity of this medium by the addition 

 of gelatin.^ The hisart reacts much sooner if it is made to contract against a 

 moderate peripheral resistance. Attention should also be called to the fact that 

 the loss of pressure during the hemorrhage permits of the occurrence of certain 

 reflexes which tend to prevent a fatal loss of blood by diminishing the force and 

 frequency of the heart beat and by constricting the bleeding vessels at the seat of 

 the injury. 



The term transfusion is applied to the procedure purposing to displace or to 

 replace a portion of the blood of an animal by the blood of another animal. ^ If ac- 

 complished by the direct method, an intimate connection is made between a blood- 

 vessel of the donor and a vein of the recipient by means of a special cannula.' 

 The blood-vessels of the forearm are generally selected if the transfusion is to be 

 performed upon man. Defibrinated blood has also been made use of, but this 

 procedure is only permissible in animal experimentation, because the defibrination 

 requires time and as the blood is subjected during this process to the influence of 

 foreign bodies, it is difficult to retain it in an aseptic condition. Moreover, as 

 the formation of fibrin is preceded by the production of certain agents which may 

 in part remain uncombined, the danger of intravascular clotting of the blood of the 

 recipient is not at all remotec The indirect method of transfusion necessitates 

 the use of a receptacle in which the blood of the donor is retained for a brief period 

 of time until permitted to flow into the veins of the recipient. This procedure is 

 also open to serious objections, because, whatever precautions are taken, the danger 

 of coagulation cannot be excluded with absolute certainty by the addition of an 

 anticoagulating agent nor by the use of oiled and paraffined receptacles. 



A method which is regarded with much favor at the present time is the so-called 

 citrate method.* Having applied a tourniquet to the arm of the donor, a cannula 

 is inserted in one of the larger veins at the elbow (median cephalic). The blood is 

 collected in a graduated cylinder containing a 2 per cent, solution of sodium citrate. 

 If 50 c.c. of blood are to be obtained, 50 c.c. of the solution are taken so that a two 

 per thousand mixture is effected. The blood is then rapidly transferred to a 

 salvarsan apparatus containing 20 to 30 c.c. of a physiological solution of 

 sodium chlorid, and is permitted to run into the punctured vein of the recipient by 

 gravitation. 



The direct transfer of blood from the donor to the patient was conceived at an 

 early date,^ and has been practised repeatedly since the middle ages, either to 

 replace blood lost by hemorrhage or to displace blood rendered useless by disease. 

 It must be conceded, however, that the high hopes entertained for this procedure 

 as a curative means have not been realized. In the first place, it is conceivable 

 that the transfer of blood from the donor through an ordinary connecting cannula 

 is liable to liberate the agents which subsequently cause intravascular clotting in 

 the recipient. An unprotected cannula acts as a foreign body, and hence, great 

 care must always be taken to keep the blood in relation with the normal lining of 



1 Bayliss, Proc. Royal Soc, London, 1917. 



2 Vogel and McCurdy, Arch. Int. Med., Dec, 1913; also see: Robertson, Jour. 

 Exp. Med., xxvi, 1917, 221. 



^Esmarch (1877) used hydrostatic pressure to force defibrinated blood into 

 the vein. In 1900 he advocated the use of normal saline solutions. The transfer 

 of blood from one human being into another through the agency of a receptacle 

 was first practised by Ziemssen (1892). 



* Carbat, Jour. Am. Med. Assoc, Ixvi, 1915; Lewisohn, ibid., Ixviii, 1917, 826, 

 and Pemberton, Surg., Gynec and Obst., xxviii, 1919, 262. 



^ Savonarola mentions the case of Pope Innocent VII who was bled and whose 

 blood was injected into two young men. These men were bled later on and their 

 blood passed into the veins of the Pope. The result, however, did not warrant 

 a repetition of this procedure, because all three men died. 



