I46 TRANSFUSION OF BLOOD. 



any part in connection with the restorative powers of the blood ; hence, defibrinated 

 blood performs all the functions of non-defibrinated blood within the body (Panum, 

 Landois). 



(d) The investigations of Worm Miiller showed that an excess of 83 per cent, of 

 blood may be transfused into the vascular system of an animal (dog) without pro- 

 ducing any injurious effects. Hence it follows that the vascular system has the 

 power of accommodating large quantities of blood within it. That the vascular 

 system can accommodate itself to a diminished amount of blood has been known 

 for a long time (, 85, c). [It is very important to observe that the transfusion of 

 a large quantity of blood does not materially or permanently raise the blood- 

 pressure.] 



When Employed. The transfusion of blood is used (1) in acute anaemia 

 ( 41, I), e.g., after copious haemorrhage. New blood (150 to 500 c.c), from the 

 same species of animal, is introduced directly into the vessels, to supply the place of 

 the blood lost by the hemorrhage. 



(2) In cases of poisoning, where the blood has been rendered useless by being 

 mixed with a poisonous substance, and hence is unable to support life. In such 

 cases remove a considerable quantity of the blood, and replace it by fresh blood. 

 Carbonic oxide is a poison of this kind, and its effects on the body have already 

 been described ( 16). A similar practice is indicated in poisoning with ether, 

 chloral, chloroform, opium, morphia, strychnine, cobra poison, and such substances 

 as dissolve the blood-corpuscles, e.g., potassic chlorate. 



(3) Under certain pathological conditions, the blood may become so altered in 

 quality as to be unable to support life. The morphological elements of the blood 

 may be altered, and so may the relative proportion of its other constituents. 

 Amongst these conditions may be cited the pathological condition of uraemia, due, 

 it may be, to the accumulation of urea or the products of its decomposition within 

 the blood ; accumulation of the biliary constituents in the blood, and great increase 

 of the carbonic acid. All these three conditions, when very pronounced, may cause 

 death. In these cases, part of the impure blood may be replaced by normal human 

 blood. 



Amongst conditions where the mwphological constituents of the blood are altered 

 qualitatively or quantitatively are : hydremia (excessive amount of water in the 

 blood, 41, 1) ; oligocythaemia (abnormal diminution of red blood-corpuscles). 

 When these conditions are highly developed, more especially in pernicious anaemia 

 ( 10, 2), healthy blood may be substituted. Transfusion is not suited for persons 

 suffering from leukaemia (compare p. 18). 



After-Effects. A quarter or half an hour after normal blood has been injected 

 into the blood-vessels of a man, there is a greater or less febrile reaction, according 

 to the amount of blood transfused (Fever, 220.) 



Operation. The operative procedure to be adopted in the process of transfusion varies accord- 

 ing as defibrinated or non-defibrinated blood is used. In order to defibrinate blood, some blood 

 is withdrawn from a vein of a healthy man in the ordinary way, collected in an open vessel, and 

 whipped or beaten with a glass rod until all the fibrin is completely removed from it. It is 

 then filtered through an atlas filter, heated to the temperature of the body (by placing it in 

 a vessel in warm water), and injected by means of a syringe into an artery opened for the 

 purpose. A vein (e.g., basilic or great saphenous) maybe selected for the transfusion, in which 

 case the blood is driven inward in the direction of the heart ; if an artery is selected (radial 

 or posterior tibial) the blood is injected towards the periphery (Hiiter), or towards the heart 

 (Landois, Schdfcr). 



If non-defibrinated human blood is used, the blood may be passed directly from the arm of 

 the giver to the arm of the receiver by means of a flexible tube. The tube used must be filled 

 with normal saline solution to prevent the entrance of air. [J. Duncan collects the blood shed 

 during an operation iu a 5 per cent, solution of sodic phosphate (Pavy), and injects the mixture 

 especially where much blood has been lost previously.] 



Dangers. It is most important that no air be allowed to pass into the circulation, for if it be 

 introduced in sufficient quantity it may cause death. When air enters the circulation it reaches 



