Hypernatraemia and Hyponatraemia 49 



of the low plasma [Na], on 19th June he excreted 210 m-equiv. of 

 sodium in three litres of urine. The plasma sodium remained low, rang- 

 ing from 109 to 123 m-equiv. /I. until August, when it gradually rose to 

 133 m-equiv. /I. Except on two occasions, both early in his illness, one 

 associated with salt deficiency and both with lung infections, he did not 

 have peripheral vascular failure. His blood urea was 26 mg. per 100 ml. 

 and the endogenous creatinine clearance 85 ml./min. 



The daily feed in these patients consisted of protein, 90 g., fat, 120 g., 

 carbohydrates, 120 g., in four litres of fluid. Until 6th July it contained 

 170 m-equiv. of sodium and thereafter 68 m-equiv., of sodium; the 

 urinary excretion of sodium fell correspondingly in both patients. 



Muscle analysis 



The question whether the total sodium content of the body 

 was low, or normal, but diluted by an excess of water in the 

 ECF could be settled by an analysis of muscle. 



Analyses of plasma taken from the two patients at the time 



OF THE muscle BIOPSY 



The specimens were taken from paralysed muscles in both 

 patients. The electrolyte contents are shown in Table I, 

 with "normal" values for specimens taken fx'om anaesthetized 



