Abstract
Because the incidences of uncomfortable symptoms caused by hemodialysis (nausea, vomiting, headache, acute hypotension etc.) are significantly reduced in bicarbonate dialysis compared with acetate dialysis, it is supposed that one of the causes of the uncomfortable symptoms is an overloading of acetate from dialysate to patients.
For the purpose of clarifying the metabolic changes in acetate loaded from acetate dialysate and the relation between the uncomfortable symptoms and acetate metabolism, plasma concentrations of organic acids, including TCA-cycle intermediate metabolites were measured during hemodialysis.
Six of the acceptable 17 patients who were on maintenance hemodialysis, received an additional 5-hours hemodialysis with the bicarbonate dialysate and 1.1m2 hollow fiber dialyser, and another 6 of the 17 patients received the acetate dialysis with 1.1m2 hollow fiber dialyser. In these patients, the plasma concentrations of acetate, lactate, pyruvate and TCA-cycle intermediate metabolites (citrate, isocitrate, α-ketoglutarate, fumarate and malate) were measured at one hourly intervals during hemodialysis.
The remaining 5 of the 17 patients received 4-hours dialysis with the acetate dialysate and a large 2.1m2 hollow fiber dialyser, and the occurrences of the uncomfortable symptoms were carefully observed.
Blood pressure and pulse rates were continuously recorded, and the plasma concentrations of acetate, citrate, malate and isocitrate were measured in succession.
The acetate dialysate contained 37mmol/l of sodium acetate and the bicarbonate dialysate contained 10mmol/l of sodium acetate and 25mmol/l of sodium bicarbonate. The organic acids were measured by means of the isotachophoresis (IP-1B, Shimadzu).
The mean plasma concentrations of acetate, citrate and malate in the patients receiving the acetate dialysis increased gradually, and these were significantly higher than those in the patients receiving the bicarbonate dialysis.
When the plasma acetate level was approximately greater than 5mM, isocitrate became detectable in the serum, and when the acetate level further incresed, the isocitrate level proportionately increased, and the uncomfortable symptoms developed at the same time. There was significant correlation between plasma levels of acetate, citrate, malate and isocitrate in the patients on the acetate dialysis.
This data suggests that some of the uncomfortable symptoms may be caused by metabolic disorders through the overloading of acetate in excess of the utilizing capacity in the patients.
