COAGULATION OF THE BLOOf) 321 



Whipple ^ ' states that the antithrombin-prothrombin balance in the 

 ■ blood is in delicate equilibrium, but preserved by strong factors of 

 ^safety. The prothrombin factor is rarely involved, most notably in 

 melena neonatorum and aplastic anemia, and such conditions may be 

 relieved by injecting normal blood, through the added prothrombin. 

 The antithroinhiu factor is often excessive in hemorrhagic conditions, 

 especially with hepatic injury, or it may be lowered and lead to throm- 

 bosis from relatively slight injuries. Obviously the injection of nor- 

 mal blood will harm rather than help patients with hemorrhage due 

 to excessive antithrnmbin. Antithrombin is often found increased in 

 diseases of the blood-forming organs, e. g., leukemia, possibly as a 

 reaction to the products of disintegration of corpuscles; and hence 

 hemorrhagic tendencies are noted in these diseases. In icterus the 

 notable tendency to hemorrhage seems to depend upon the binding of 

 the calcium of the blood by the bile pigments,**' and administration 

 of calcium may bring the coagulation time back to normal with a cor- 

 responding decrease in the hemorrhagic tendency. 



PfeifPer ^' estimated the fibrin content of the blood in disease, and 

 found it increased in diseases with leucocytosis (pneumonia, rheuma- 

 tism, erysipelas, scarlet fever), except leukemia, where it was normal; 

 in diseases without leucocytosis (typhoid, malaria, nephritis), the 

 fibrin was normal in amount. Stassano and Billon *^ have, further- 

 more, shown that the amount of fibrin-ferment varies directly with 

 the number of leucocytes in the blood. Kollmann *'-^ found an increase 

 in the fibrin of eclampsia, wdiich Lewinski ^° could not substantiate. 

 In experimental infections of animals Langstein and ^Mayer ^^ found 

 a specific increase in pneumococcus sepsis, which undoubtedly bears 

 an important relation both to the characteristic fibrinous nature of 

 the alveolar exudate in pneumonia, and the striking amount of fibrin 

 found in pneumococcus pleuritis, peritonitis, etc. ^Mathews ^'- found 

 an increase in the fibrin with all experimental suppurations. 



The coagulation time of the drawn blood has been the subject of 

 much study by various methods,^^ but as yet very little agreement has 

 been obtained. By different methods, in which different conditions 

 for coagulation are presented, the normal coagulation time varies from 

 2 to 30 minutes ; with most methods it is 5 to 8 minutes. In general, 



by Bell (Jour. Path, and Bact., 1914 (18), 462) and to an excess of antitlirombin 

 bv Dienst (Miinch. med. Woch., 1912 (51), 2709). 



45 Arch. Int. Med.. 1913 (12), 037. 



46 Lee and Vincent, Arch. Int. Med., 1915 (16), 59. 



.47Zeit. klin. Med.. 1897 (33), 214: Cent. f. inn. Med., 1S9S (19). 1. 

 48Compt. Rend; Soc. Riol., 1903 (55), 511. 

 49 Cent. f. Gvniik., 1897 (21). .341. 

 sopfliitrer's Arch., 1903 (100), 611. 



51 Hofmeister's Beitr.. 1903 (5), 69. 



52 Amer. Jour. Physiol.. 1899 (3), 53. 



53 Full review and bibliography by Cohen, Arch. Int. Med., 1911 (8), 684 and 

 820. 



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