2 94 PROD UCTION AND ABSORPTION OF L YMPH. 



%Hb 



FIG. 40. Diagram to show the dilution of the 

 blood (i. e. hydrcemic plethora) produced in 

 dogs (Experiments 1, 2, 3, 4) by the injec- 



containing from 50 to 75 per cent, of dextrose, it will attract fluid from 



the tissues until its percentage 

 is reduced to 5 or 6 per cent. ; 

 that is to say, 45 c.c. of fluid 

 containing 30 grms. of dextrose 

 will attract water from the tissues 

 until its total volume is increased 

 to 500 c.c. Of course this esti- 

 mate is merely a rough approxi- 

 mation at the truth, since before 

 the sugar has had time to attract 

 all this fluid, a considerable 

 Amount of it will already have 

 left the vessels by diffusion. As 

 a matter of fact, however, we find 



w . , 4 that injection of a strong solu- 



tion of 5 grms. dextrose per kilo, body- ti f c l extrose is followed in a 

 weight. The ordinates represent the . ., ,, 



volume of the blood (compared with the few minutes by a considerabl 



normal) as indicated by percentage of dilution of the blood, caused by 

 hemoglobin. The abscissa represent inter- increase in its volume. In 



vals of five minutes. The line AA n marks . e , , 



the time at which the injection was finished some experiments of von Brasol, 1 



in each experiment. The dotted lines to the volume of the circulating 

 the left of AAj indicate the theoretical diln- blood wag thug uicreas ed to twice 

 tion effected by the volume of fluid injected. 1 , , . . , 



-After J. B. Leathes. or three times its previous 



amount; and these observations 



have been fully confirmed in a series of careful experiments made by 

 J. B. Leathes 2 (Fig. 40). 

 As we should expect, 60 

 this increase in the vol- 

 ume of the circulating 

 blood is attended by a 

 large rise of capillary 

 pressure in the abdomi- 

 nal viscera (Fig 41), and 

 we have here again to 

 decide whether it is this 

 rise of capillary pressure, 

 or the change in the 

 chemical composition of 

 the blood, that determines 

 the increased lymph flow. 

 This question can be 

 solved by using the same 

 method that we adopted 

 when dealing with the 

 production of the in- 

 creased lymph flow in 

 hydrsemic plethora. We 

 can entirely obviate the 

 rise of capillary pressure 



01 6 !b 20 so 40 5o so minutes 



Inj. of 40 grams dextrose 



FIG. 41. To show influence of the intravenous injection 

 of dextrose on the blood pressure in the abdominal 

 viscera, and on the lymph flow from the thoracic duct. 

 The upper dotted line = pressure in portal vein. The 

 lower clotted line = pressure in inferior vena cava. 

 The thick continuous line = pressure in aorta. The 

 thin continuous line = lymph flow. The ordinates 

 represent venous pressure in centimetres of water, 

 arterial pressure in centimetres Hg, and lymph flow 

 in cubic centimetres per ten minutes. 



if we bleed first to 300 c.c. and then inject a concentrated solution 



1 Arch.f. PhysioL, Leipzig, 1884, S. 211. 



2 Journ. PhysioL, Cambridge and London, 1895, vol. xix. p. 1. 



