314 DISTURBANCES OF CIRCULATION 



Probably only the first two factors apply to the connective-tissue 

 growth observed in the congested spleen, the clubbing of the fingers 

 in congenital heart disease, or the thickening of the subcutaneous 

 tissues in passive congestion of the lower extremities. 



Changes in the Blood. — Venous blood differs from arterial, not 

 only in its increased load of CO2 and other waste products, but also 

 in other ways. Venous blood generally clots less readily than arterial 

 blood. *^ It contains more diffusible alkali because the CO2 combines 

 with and tears away part of the bases that are held by the proteins, 

 especially in the corpuscles, and so alkaline carbonates are formed 

 and enter the plasma. Blood from the jugular vein on this account 

 contains 20-25 per cent, more diffusible alkali than carotid blood 

 (Hamburger).'*^ Since the bactericidal power of the blood has been 

 shown to increase directly with the alkalinity, this property may be 

 of importance in pathology. For example, the relative infrequency 

 of infections in the right side of the heart may not depend solely upon 

 lessened liability to endocardial damage, as generally considered, but 

 is possibly due in part to the greater bactericidal power of venous 

 blood. The same property probably explains the favorable results 

 obtained in the treatment of local infections by artificially produced 

 passive congestion. ^^ Too severe a stasis, with resultant edema, prob- 

 ably favors local infection.^" 



V. Fodor^^ found that animals surviving infections show an in- 

 creased blood alkalinity, whereas in those that died, the alkalinity 

 was decreased; also, he found the resistance increased b}^ intravenous 

 injections of alkalies. Other observers^- have noted a decrease in re- 

 sistance after injecting acids into the blood. According to Calabrese, 

 the alkalinity of the blood increases in immunization of animals 

 against toxins, while Cantani found the injection of toxin followed 

 by a decrease in alkalinity. Hamburger has shown that the bac- 

 tericidal power of the blood may be increased in vitro bj^ shaking it 

 with CO? as a result of the increased alkalinity, aided, perhaps, by 

 some slight bactericidal power of the CO2 itself; he also found the 

 blood more strongly bactericidal in venous congestion than normally, 

 and the lymph from a congested part was also found more strongly 

 bactericidal than normal lymph. Hamburger^^ has also found, how- 

 ever, that chemotaxis is, if anything, slightly decreased under the in- 

 fluence of CO2, as also is phagocytosis; large amounts of CO2 may 



^'Vierordt (Arch. f. lleilk., 1S7S (19), 19:5) found coa{i;ul:ition faster in the 

 l)lood in passive conj>;estion than in normal venous blood; but Ihisebrock (Zcit. f. 

 Biol., 1882 (18), 41) found that if the stasis is protracted, the coagulation becomes 

 delayed because of the excess of COa- 



•"* Virchow's Arch., 1S99 (150), 329; also. "Osmotischcr Druck und lonenlehre." 



" Hee Bier, "IIypcr;emie als lleilmittel," Leipsic, 1903. 



'0 Glasewald, C-ent. Chenz. Med. Chir., 1915 (IS), 507. 



f" Cent. f. Bakt., 1S90 (7), 753. 



•■^ Literature, see Ibunburf^er (loc. citJ'*), p. 281 



'"•' Virchow's Arch., 1899 (150), 329. 



