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Scientific Proceedings (127) 



blood there is also a pronounced numerical deficiency in blood 

 platelets. In purpura hemorrhagica, in which such a reduction 

 in the number of platelets is regularly present, the injection of 

 sodium citrate may be followed by almost complete disappear- 

 ance of platelets from the circulating blood. In both these dis- 

 eases and in congenital hemophilia, in which there is presumed 

 to be some deficiency in the quality of blood platelets, the injec- 

 tion of sodium citrate is followed by a prolongation in the coag- 

 ulation time, a further diminution of the blood platelets and by 

 a marked increase in the bleeding tendency. 



8. The characteristic shortening of coagulation time does 

 follow intravenous administration of sodium citrate in cases of 

 obstructive jaundice, in which, although the coagulation time is 

 prolonged and there is a bleeding tendency ; the blood platelets in 

 this condition are normal in number and unaffected. 



Sufficient evidence has therefore been presented to indicate 

 that the shortening of coagulation time after injection of sodium 

 citrate in normal individuals or animals is due to some influence 

 on the blood platelets. That this is not a direct destruction is 

 indicated by the test tube experiment and by the fact that the 

 maximum shortening of coagulation time does not occur simul- 

 taneous with the maximum reduction in platelets, but follows 

 at some time between ten minutes to one hour later. 



This sequence suggests that the platelets after contact with 

 the citrate are damaged and removed from the circulation by 

 some organ, there destroyed and their thromboplastic contents 

 gradually liberated into the blood stream. The removal and 

 destruction of damaged blood platelets is probably one of the 

 functions of the spleen, especially in view of the role which it is 

 presumed to play in the thrombopenia of purpura hemorrhagica. 



Based upon these observations the slow intravenous injection 

 of large doses of sodium citrate up to five grams has been suc- 

 cessfully employed in arresting internal hemorrhages due to 

 gastric ulcer, typhoid fever, pulmonary tuberculosis, etc., and 

 also as a pre-operative prophylactic measure in obstructive jaun- 

 dice. In hemorrhagic blood diseases for reasons detailed above, 

 its use is strictly contraindicated. 



