Evaluation of Metabolic Acidosis in Chronic Hemodialysis Patients

Sung-Sen Yang ； Shih-Hua Lin ； Weng-Sheng Tsai ； Jih-Guang Juang ； Yuh-Feng Lin

《Journal of Medical Sciences》 22卷4期 (2002/08) Pp. 165-169

並列摘要

Objective: Metabolic acidosis is not uncommonly seen in uremic patients on regular hemodialysis (HD). The purpose of this study was to assess the basis for metabolic acidosis in chronic stable HD patients. Methods: Twenty-eight chronic stable HD patients dialyzed three times weekly, with the same dialyser and dialyste flow rate, were enrolled n this study. Their acid-base status was obtained before and 30 minutes after the regular HD session in the middle week. Metabolic acidosis was defined as pH ＜ 7.37 and plasma bicarbonate concentration (Pнсо₃) ＜ 20 mmol/L. Biochemical parameters, normalized protein catabolic rate (nPCR), three-day dietary protein intake (DPI), and intradialytic HCO₃⁻ gain were measured. Results: Ten patients exhibited metabolic acidosis (pH 7.34±0.02, Pнсо₃ 18.8±0.3 mmol/L) and the other 18 patients did not (pH 7.40±0.04, Pнсо₃ 22.3±0.4 mmol/L). There was no significant difference in age, sex, duration of dialysis, ultrafiltration volume, and Kt/V. However, body mass index, predialysis blood urea nitrogen, creatinine concentrations, nPCR, DPI, and intradialytic HCO₃⁻ gain were significantly higher in the acidotic group (p＜0.05). The predialysis Pнсо₃ was inversely correlated with nPCR (r=-0.64, p＜0.001), DPI (r=-0.58, p＜0.01), and intradialytic HCO₃⁻ gain (r=-0.65, p＜0.01). Conclusions: Metabolic acidosis in well-dialyzed chronic stable HD patients is caused by higher protein intake with a higher acid production rather than inadequate dialysis HCO₃⁻ gain or hypercatabolic state with low protein intake.

並列關鍵字

hemodialysis ； intradialytic bicarbonate gain ； metabolic acidosis ； uremia