Cramps, thirst and hypertension in hemodialysis patients -- the influence of dialyzate sodium concentration.

The effect of increasing dialyzate sodium concentration from 130 to 136 mmoles/l on the incidence of muscle cramps in patients on regular dialysis treatment is assessed. This change was found to be effective in markedly reducing the incidence of cramp at the cost of a slight rise in the complaint of thirst. Mean arterial pressure rose slightly but significantly and exchangeable sodium was increased to levels comparable to those measured during 1969, when with twice weekly dialysis hypertension was a problem. It is concluded that dialyzate sodium concentration may with benefit be increased to 136 mmoles/l, provided that blood pressure is carefully monitored.