We compared the effects of dialysate composition on changes in intermediary metabolites, acid-base balance, and potassium removal during hemodialysis. Patients were dialyzed against dialysates containing acetate or bicarbonate, each with or without glucose, in a four-way cross-over study. Dialysates containing acetate were associated with significant perturbations in intermediary metabolism, including increases in blood citrate, acetoacetate and beta-hydroxybutyrate and a decrease in pyruvate. In contrast, bicarbonate-containing dialysates caused minimal perturbations in intermediary metabolism. Addition of glucose to the dialysate decreased the changes in intermediary metabolites; however, the magnitude of this effect was less than that observed for the change from acetate to bicarbonate. Use of acetate also resulted in lower post-dialysis blood-concentrations of base equivalents than obtained with bicarbonate; this difference was unaffected by the presence or absence of glucose. Although pre- and post-dialysis potassium concentrations were unaffected by the dialysate formulation, total potassium removal was significantly greater when glucose was omitted from the dialysate. Our results suggest that both bicarbonate and glucose should be included in the dialysate, particularly for those patients whose capacity for metabolism may be limited because of highly efficient dialysis, intercurrent illness, or starvation. However, addition of glucose to the dialysate may require a reduction in dialysate potassium to maintain proper potassium homeostasis.

Renin release was studied during the infusion of catecholamines (.7–5.6 µg/min) and angiotensin II (.25–1.05 µg/min) into the renal artery, and also during and following iv infusion of 16 µg/min noradrenaline. Filtration rate (Ccr), RPF, and RBF were estimated from the renal clearance of creatinine and the extraction ratio. Marked increases in renal vein renin titer and V-A renin difference occurred within 1 min of the onset of infusion of catecholamine into the renal artery and continued for 15 min beyond the infusion period. This infusion was always accompanied by diminished renal function. During iv infusion of noradrenaline, renin release did not usually occur, but on stopping the iv infusion, the ensuing fall in blood pressure was coincident with a marked release of renin apparently unaccompanied by decreased renal function. Infusion of angiotensin into the renal artery, in spite of causing renal vasoconstriction and marked decrease in urine volume, was not accompanied by renin release. The difficulties of measuring renin release under these conditions are discussed.

The present study compares some of the metabolic effects of hemodialysis of fasting patients with and without glucose in the dialysate bath. Unlike glucose dialysis, glucose-free dialysis caused marked decreases in blood levels of glucose, insulin, lactate, and pyruvate along with profound increases in acetoacetate and beta-hydroxybutyrate. It is concluded that oxidation of fatty acids increases to meet energy demands and that the combined processes of glycogenolysis and gluconeogenesis serve to prevent critical hypoglycemia during glucose-free dialysis.

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