Acid-Base Balance in Dialysis Patients: A Reassessment (original) (raw)

Acid-base balance in chronic peritoneal dialysis patients

Kidney International, 1995

Acid-base balance in chronic peritoneal dialysis patients. Endogenous acid production has never been measured directly in dialysis patients and an empiric formula is used to estimate acid production from their protein catabolic rate. We have studied acid-base balance in 19 stable CAPD patients attending the peritoneal dialysis clinic of Mount Sinai Hospital. They obtained a 24 hour collection of peritoneal dialysis fluid and urine while consuming their usual diet and performing their usual activities.

Opinion: What Unique Acid-Base Considerations Exist in Dialysis Patients?

Seminars in Dialysis, 2004

Because a typical modern diet results in net production of acid, and the kidney is normally the main organ responsible for generating alkali to maintain acid-base homeostasis, chronic metabolic acidosis is commonly observed in patients with chronic renal insufficiency. In this article we will deal with the clinical characteristics, pathophysiology, and therapeutic approach to this condition.

ACID-BASE IN RENAL FAILURE: Acidosis and Nutritional Status in Hemodialyzed Patients

Seminars in Dialysis, 2001

In a cross-sectional study of more than 30% of French dialysis patients (N = 7,123), we evaluated the relationships between predialysis plasma bicarbonate concentration and nutritional markers. Data including age, gender, cause of end-stage renal disease (ESRD), time on dialysis, body mass index (BMI), blood levels of midweek predialysis albumin, prealbumin, and bicarbonate were collected. Normalized protein catabolic rate (nPCR), dialysis adequacy parameters, and estimation of lean body mass (LBM) were computed from pre-and postbicarbonate-dialysis urea and creatinine levels according to the classical formulas of Garred. Average values (±1 SD) were age 61 ± 16 years, BMI 23.3 ± 4.6 kg/m 2 , dialysis time 12.4 ± 2.7 h/week, HCO 3 22.8 ± 3.5 mmol/L, albumin 38.7 ± 5.3 g/L, prealbumin 340 ± 90 mg/L, Kt/V 1.36 ± 0.36, nPCR 1.13 ± 0.32 g/kg BW/day, and LBM 0.86 ± 0.21% of ideal LBM. A highly significant negative correlation was observed between predialysis bicarbonate levels (within a range of 16-30 mmol/L, 95% of this population) and nPCR confirmed by analysis of variance using bicarbonate classes (p < 0.0001). Bicarbonate was also negatively correlated with albumin, prealbumin, BMI, and LBM. No relationship was noted between bicarbonate and Kt/V despite a positive correlation between Kt/V and nPCR. It is likely that a persistent acidosis observed despite standard bicarbonate dialysis was caused by a high dietary protein intake which results in an increased acid load, but also overcomes the usual catabolic effects of acidosis.

Characterization of acid-base status in maintenance hemodialysis: physicochemical approach

Journal of artificial organs : the official journal of the Japanese Society for Artificial Organs, 2008

Acidosis is a common and deleterious aspect of maintenance dialysis. Traditionally, it is considered to be an elevated anion gap acidosis caused by the inability to excrete nonvolatile anions. Stewart's approach made it possible to identify real determinants of the acid-base status and allowed quantification of the components of these disturbances, especially the unmeasured anions. We performed a cross-sectional study to identify and quantify each component of acidosis in hemodialysis maintenance patients. Sixty-four maintenance hemodialysis patients and 14 controls were enrolled in this study. Gasometrical and biochemical analysis were performed before the midweek dialysis session. Quantitative physicochemical analysis was carried out using the Stewart methodology. Hemodialysis patients were found to have mild acidemia (mean pH: 7.33 +/- 0.06 versus 7.41 +/- 0.05) secondary to metabolic acidosis (serum bicarbonate: 18.8 +/- 0.26 versus 25.2 +/- 0.48 mEq/l). The metabolic acidos...

Acidosis and nutritional status in hemodialyzed patients. French Study Group for Nutrition in Dialysis

Seminars in …, 2000

In a cross-sectional study of more than 30% of French dialysis patients (N = 7,123), we evaluated the relationships between predialysis plasma bicarbonate concentration and nutritional markers. Data including age, gender, cause of end-stage renal disease (ESRD), time on dialysis, body mass index (BMI), blood levels of midweek predialysis albumin, prealbumin, and bicarbonate were collected. Normalized protein catabolic rate (nPCR), dialysis adequacy parameters, and estimation of lean body mass (LBM) were computed from pre-and postbicarbonate-dialysis urea and creatinine levels according to the classical formulas of Garred. Average values (±1 SD) were age 61 ± 16 years, BMI 23.3 ± 4.6 kg/m 2 , dialysis time 12.4 ± 2.7 h/week, HCO 3 22.8 ± 3.5 mmol/L, albumin 38.7 ± 5.3 g/L, prealbumin 340 ± 90 mg/L, Kt/V 1.36 ± 0.36, nPCR 1.13 ± 0.32 g/kg BW/day, and LBM 0.86 ± 0.21% of ideal LBM. A highly significant negative correlation was observed between predialysis bicarbonate levels (within a range of 16-30 mmol/L, 95% of this population) and nPCR confirmed by analysis of variance using bicarbonate classes (p < 0.0001). Bicarbonate was also negatively correlated with albumin, prealbumin, BMI, and LBM. No relationship was noted between bicarbonate and Kt/V despite a positive correlation between Kt/V and nPCR. It is likely that a persistent acidosis observed despite standard bicarbonate dialysis was caused by a high dietary protein intake which results in an increased acid load, but also overcomes the usual catabolic effects of acidosis.

Metabolic acidosis and its association with nutritional status in hemodialysis

Jornal Brasileiro de Nefrologia, 2015

Metabolic acidosis is a common problem in dialysis patients and plays an important role in the pathogenesis of protein-energy malnutrition in these patients. Objectives: To assess the prevalence of metabolic acidosis in hemodialysis and search their association with nutritional status. Methods: A cross-sectional study was performed in hemodialysis patients at a single center. Nutritional status was assessed by anthropometric, biochemical and multifrequency bioelectrical impedance analysis. Metabolic acidosis was defined as serum bicarbonate (BIC) < 22 mEq/L and patients were divided into 3 groups according to BIC (< 15.15 to 21.9 and ≥ 22). The association between BIC and continuous variables was investigated using the Kruskal Wallis test. The linear correlation between BIC and the variables of the study was also tested. Results: We studied 95 patients, 59% male, mean age 52.3 years. The prevalence of metabolic acidosis was 94.7%. BMI, interdialytic weight gain and PTH were significantly different among the 3 groups of BIC. The BIC was negatively correlated with urea, phosphorus and interdialytic weight gain. There was no significant correlation with albumin, phase angle and lean body mass index. Conclusion: The prevalence of metabolic acidosis was high in this population, and a lower BIC correlated with higher levels of urea, PTH, phosphorus, interdialytic weight gain and lower BMI. The evaluation of acid-basic status should be routinely implemented in dialysis patients by considering the negative effects of acidosis on the nutritional status, inflammation and bone disease.

Effect of First Session Dialysis on Acid

International journal of health sciences

Background: MA results from the inability of the kidneys to eliminate acid load, leading to HCO3- depletion and accumulation of H+, the more deterioration of renal function the more severity of acidosis, In AKI, acidosis is a traditional and typical complication, and refractory acidosis is an indication for renal replacement therapy. Aim: to study the effect of first dialysis session on acidosis correction. Methods: an interventional study included 33 patients with renal failure presented for 1st time dialysis, we calculated the change in their pH, HCO3-, BD, AG and Cl- to Na+ ratio caused by dialysis, and studied whether or not this change is related to URR. Results: dialysis had significant effect on pH, HCO3- and BD, and there was positive correlation between URR and HCO3- difference and negative correlation between both BD difference with HCO3- difference, and BD difference with HCO3- difference. Conclusion: 1st dialysis session has significant effect on acidosis correction with...

ACID-BASE STATUS OF PREVALENT PERITONEAL DIALYSIS PATIENTS : RDPLF DATA Statut acido-basique des patients prévalents en dialyse peritoneale Données du RDPLF

2019

Acid-base status of patients on peritoneal dialysis is influenced by multiple factors. Metabolic acidosis is a common feature of chronic renal failure and dialysis treatment provides alkali in the dialysate in order to maintain a normal acid-base balance. This paper reports the prevalence of acid-base disorders in peritoneal dialysis patients and their associations with clinical and laboratory parameters. This is a cross-sectional retrospective study that included all PD patients registered in the RDPLF database. Metabolic acidosis was found in 20.4% of patients while 27.8% of patients had metabolic alkalosis. There is a significant relationship between age, protein intake estimated by nPNA and the level of alkaline reserve pleading in favor of the influence of dietary intakes in the maintenance of metabolic acidosis. Low residual renal function is associated with a lower probability of being in metabolic alkalosis. These results could allow an individual choice of the dialysate buf...

Association of acidosis and nutritional parameters in hemodialysis patients

American Journal of Kidney Diseases, 1999

There is extensive literature supporting an important role for acidosis in inducing net protein breakdown, both in experimental animals and humans. However, the clinical importance of the moderate intermittent metabolic acidosis frequently observed in hemodialysis patients has not been determined. We performed a cross-sectional analysis of the baseline laboratory data in the first 1,000 patients recruited to the Hemodialysis Study, looking for correlations between predialysis serum total carbon dioxide levels and parameters related to dietary intake and nutritional status. We found the mean predialysis serum total carbon dioxide level was moderately low (21.6 ؎ 3.4 mmol/L; mean ؎ SD) despite the use of bicarbonate dialysate and an average single-pool Kt/V of 1.54. Predialysis serum total carbon dioxide level correlated negatively with normalized protein catabolic rate (P F 0.001), suggesting patients with lower serum total carbon dioxide levels have a greater protein intake. The degree of acidosis observed in our patients does not seem to have a deleterious effect on the nutritional status of these patients because correlation of serum total carbon dioxide level with nutritional parameters, such as serum creatinine and serum albumin levels, was either negative or not statistically significant. Further investigation of the effect of modifying serum bicarbonate concentration on nutritional markers is needed to test these hypotheses.