The Chlor des of the Plasma in Uremia. 167 



That increased acidity of the blood causes a diminution of the 

 plasma chlorids, and an increase in the chlorid content of the cells 

 had been shown experimentally both in vitro and in vivo by 

 Hamburger. 1 That a similar change occurs with the increased 

 acidity of the blood in uremia is illustrated by the following case 

 of nephritis, terminating in uremia. 



Case 1. P. W. M., male, age 44, chronic interstitial nephritis, 

 uremia. Patient admitted June 17, suffering with chronic in- 

 terstitial nephritis, hypertension and secondary cardiac failure 

 with edema. With rest in bed the heart condition rapidly im- 

 proved and the edema disappeared. Following this the patient 

 felt well and the condition remained stationary, until October 12, 

 when an impending uremia first became manifest by an increase in 

 the blood urea and a diminished urea excretion. From June 17 

 to October 6 there were made twenty blood analyses, with simul- 

 taneous urine analyses, and the results showed very slight varia- 

 tion. The average of the figures for this period is shown below. 

 The maximum concentration of NaCl in the plasma during this 

 period was 6.53 grams per liter and the minimum was 6.06. The 

 phthalein elimination, shortly after admission, was twice found 

 to be 8 per cent, in two hours. 2 



It will be seen from the table that the diminished urea function, 

 beginning about two weeks before symptoms of uremia appeared, 

 was accompanied by a diminution in the reserve alkalinity of the 

 plasma, as shown by Van Slyke's method. On October 29 an 

 actual increase in acidity, as shown by the P H of the blood, was 

 present and there had been a sudden fall in the chlorid concentra- 

 tion of the plasma. This concentration remained low thereafter 

 until death, and the change was far greater than could possibly be 

 accounted for by the diminished diet. The change in NaCl con- 

 centration in the plasma is exactly that produced by intravenous 

 injection of any acid, in quantities sufficient to change the P H of 

 the blood, and is accounted for by the increased acidity of the 

 blood occurring during the disease. 



1 Hamburger, H., " Osmotischer Druck und Ionenk'hrc," Wiesbaden, 1902, I, 317. 



2 The observations on urea and chlorid elimination were made by the methods 

 previously described by the author (Jour. Exper. Med., 1915, XXII, 212 and 366). 

 Plasma CO2 was determined by the method of Van Slyke (Proc. Soc. Exp. Biol, 

 and Med., 1915, XII, 165). For the determination of hydrogen ion concentration 

 in the whole blood by the gas chain method, I am indebted to Mr. G. E. Cullcn. 



