Potassium Balance and Acid-Base Changes in Patients Undergoing Regular Haemodialysis TherapyBr Med J 1970; 1 doi: https://doi.org/10.1136/bmj.1.5699.779 (Published 28 March 1970) Cite this as: Br Med J 1970;1:779
- A. G. Morgan,
- L. Burkinshaw,
- P. J. A. Robinson,
- S. M. Rosen
Serial measurements of total body potassium in 21 patients with chronic renal failure being treated with three 10-hour periods of dialysis per week, against a dialysate fluid containing 1·5 mEq of potassium per litre, showed no evidence of potassium depletion. Mild hyperkalaemia was found in some patients before dialysis, correlated with the pre-dialysis hydrogen ion concentration. Hypokalaemia occurred during dialysis in almost half of the studies made; the plasma potassium concentration, however, rose to normal levels within two to four hours of stopping dialysis. A delay in the movement of potassium from the cells into the extracellular fluid is suggested as a cause for the observed hypokalaemia.
In all but one patient the pre-dialysis blood pH was normal, but rose to alkalaemic levels during dialysis. A pronounced degree of hypocapnia was noted before dialysis, and this was not altered by a rising blood pH during dialysis. It is suggested that a stimulus to respiration other than the hydrogen ion gradient between the brain cells and cerebral spinal fluid may produce the observed hypocapnia.