Effects of acetate and bicarbonate dialysis on cardiac performance, transmural myocardial perfusion and acid-base balance.

The effects of acetate and bicarbonate dialysis on cardiac performance, myocardial oxygen balance and acid-base balance were evaluated in 7 patients with end-stage renal failure. During acetate dialysis cardiac output increased and was significantly higher than during bicarbonate dialysis (p less than 0.05). Systemic vascular resistance was significantly lower during acetate than during bicarbonate dialysis (p less than 0.05). The myocardial oxygen balance estimated from the supply/demand ratio (DPTI/SPTI) was significantly reduced after acetate dialysis and significantly lower than during bicarbonate dialysis (p less than 0.05). After 90 min acetate dialysis DPTI/SPTI dropped to its lowest value as a result of an excess of myocardial oxygen demand (SPTI) over myocardial oxygen supply (DPTI), signifying transient hypoperfusion of the subendocardium which did not occur during bicarbonate dialysis. Acidosis was more adequately corrected with bicarbonate dialysis, and there was no change in pCO2 which was significantly higher than during acetate dialysis (p less than 0.05). During bicarbonate dialysis a stable hemodynamic circulation and well balanced acid-base values were seen. Acetate dialysis leads to improvement in left ventricular performance, but at the expense of myocardial oxygen balance, which falls to marginal safety levels in uremic patients.