302 DISTURBANCES OF CIRCULATION 



formerly held tliat oxidation is decreased in anemia has been con- 

 siderably modified by more recent investig'aticms;^" in fact, respira- 

 tion stndies indicate heightened gas exchange in secondary anemia.*"* 



Secondary anemia due to cachexia, or to malnutrition, is accom- 

 panied ])y a general decrease in all the elements of the blood, both 

 cellular and chemical. The proteins of the plasma, particularly, show 

 a decrease in starvation, being drawn on by the cells for food, and 

 the total quantity of blood as well as of each of its constituents is de- 

 creased (Panum),*^ but the proportion of blood to body weight re- 

 mains about normal. With protracted starvation there is only a 

 slight loss of hemoglobin and an increased coagulability, but practi- 

 cally no other changes.'*^'' In aplastic anemias the prothrombin and 

 platelet content are likely to be low, with normal fibrinogen. ^^'^ 



Anemia due to hemolytic agencies presents quite different fea- 

 tures, in that red corpuscles are almost solely attacked and the prod- 

 ucts of their disintegration are present in the plasma. As a result, 

 the plasma or serum may contain free hemoglobin, and if the hemo- 

 globin is in large amounts, it may escape into the urine. Thus par- 

 oxysmal hemoglohinuria. is probably due to the presence in the blood 

 of hemolytic substances, which can be demonstrated in the blood of 

 the patients during the attack. (See Chapter viii.) The products 

 of the decomposition of the hemoglobin set free by hemolysis are 

 present not only in the blood, but also in the organs, particularly the 

 liver and spleen, which become rich in iron. In acute anemia pro- 

 duced by hemolytic sera, with destruction of more than half the blood 

 in three days, nearly all the iron from the destroyed hemoglobin can 

 be found in the liver, spleen and kidneys, there being but little lost 

 through the urine even in so severe an anemia as this (INIuir and 

 Dunn).*^" Excretion of bile-pigments increases, and ^^hematogenous 

 jaundice" may result, the bile-pigments that are present in the blood 

 being derived from the hematoidin of the hemoglobin molecule. 

 Changes in metabolism occur which are quite similar to those ob- 

 served in other forms of anemia, with fatty changes in all the paren- 

 chymatous organs, increased protein katabolism, and an excessive 

 quantity of pigmentary substances, particularly urobilin, in the urine. 



CHLOROSIS 



The characteristic feature of the blood in chlorosis is the rela- 

 tively small amount of licmoglobin in pro])()rtion to the number of 

 corpuscles. Apparently, therefore, the fault lies rather in the manu- 



40 See Mohr, Zeit. exp. Path.. lOOfi (2), 4.35. 

 40aGrafe, Deiit. Arch. klin. Med.. 11)1,'> (US), 14S. 



41 Virchow's Arch., 1864 (20), 241. 

 4iaA8h. Arch. Int. Med., 1014 (14), 8. 



41b Drinker and Ilurwitz, Arch. Int. Med, I'M.') (If)), 73:]; Jour. Exp. yied., 

 1915 (21), 401. 



4ic Jour. Patli. and I'-act.. IDlf) (10), 417. 



