Abstract
Hyperpotassemia is often encountered in regugarly hemodialyzed patients. However, excessive potassium (K) intake does not always cause it. To evaluate the K homeostasis in chronic dialyzed patients, we measured the amount of K removed by hemodialysis (HD) as well as the erythrocyte K concentration (RK) before and after HD. The mean value of K removed by HD was 56.0±10.4mEq (11.9-259.5mEq). The amount of removed K showed linear correlation with the serum K concentration before HD and the K concentration difference before and after HD (Y=31.9X-96.5, r=0.59, p<0.01, Y=41.7X+1.43, r=0.55, p<0.01, respectively).
RK was 94.8±4.3mEq/l cell before HD and 93.3±3.9mEq/l cell after HD. These values were significantly lower than that in normal subjects, but were not significantly different from each other. The change of RK by HD and the difference between measured removed K and estimated removed K, which was calculated by the change of serum K concentration by HD, showed a significant statistical correlation (Y=0.46X-0.73, r=0.69, p<0.01). These data showed that in some chronic hemodialyzed patients, K entered into the intracellular space during HD, while in others, K was removed from the intracellular fluid by HD.
Thus, we conclued that it might be questionable to estimate the K homeostasis only by the change of plasma K concentration during HD.
