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Leypoldt JK, Pietribiasi M, Debowska M, Wieliczko M, Twardowska-Kawalec M, Malyszko J, Waniewski J. Validity of the hydrogen ion mobilisation model during haemodialysis with time-dependent dialysate bicarbonate concentrations. Int J Artif Organs 2023; 46:507-513. [PMID: 37288535 DOI: 10.1177/03913988231179233] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
BACKGROUND The hydrogen ion (H+) mobilisation model has been previously shown to accurately describe blood bicarbonate (HCO3) kinetics during haemodialysis (HD) when the dialysate bicarbonate concentration ([HCO3]) is constant throughout the treatment. This study evaluated the ability of the H+ mobilization model to describe blood HCO3 kinetics during HD treatments with a time-dependent dialysate [HCO3]. METHODS Data from a recent clinical study where blood [HCO3] was measured at the beginning of and every hour during 4-h treatments in 20 chronic, thrice-weekly HD patients with a constant (Treatment A), decreasing (Treatment B) and increasing (Treatment C) dialysate [HCO3] were evaluated. The H+ mobilization model was used to determine the model parameter (Hm) that provided the best fit of the model to the clinical data using nonlinear regression. A total of 114 HD treatments provided individual estimates of Hm. RESULTS Mean ± standard deviation estimates of Hm during Treatments A, B and C were 0.153 ± 0.069, 0.180 ± 0.109 and 0.205 ± 0.141 L/min (medians [interquartile ranges] were 0.145 [0.118,0.191], 0.159 [0.112,0.209], 0.169 [0.115,0.236] L/min), respectively; these estimates were not different from each other (p = 0.26). The sum of squared differences between the measured blood [HCO3] and that predicted by the model were not different during Treatments A, B and C (p = 0.50), suggesting a similar degree of model fit to the data. CONCLUSIONS This study supports the validity of the H+ mobilization model to describe intradialysis blood HCO3 kinetics during HD with a constant Hm value when using a time-dependent dialysate [HCO3].
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Affiliation(s)
- John Kenneth Leypoldt
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Poland
| | - Mauro Pietribiasi
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Poland
| | - Malgorzata Debowska
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Poland
| | | | | | | | - Jacek Waniewski
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Poland
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Gennari FJ, Marano M, Marano S. Replenishing Alkali During Hemodialysis: Physiology-Based Approaches. Kidney Med 2022; 4:100523. [PMID: 36032503 PMCID: PMC9411655 DOI: 10.1016/j.xkme.2022.100523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The acid-base goal of intermittent hemodialysis is to replenish buffers consumed by endogenous acid production and expansion acidosis in the period between treatments. The amount of bicarbonate needed to achieve this goal has traditionally been determined empirically with a goal of obtaining a reasonable subsequent predialysis blood bicarbonate concentration ([HCO3-]). This approach has led to very disparate hemodialysis prescriptions around the world. The bath [HCO3-] usually chosen in the United States and Europe causes a rapid increase in blood [HCO3-] in the first 1-2 hours of treatment, with little change thereafter. New studies show that this abrupt increase in blood [HCO3-] elicits a buffer response that removes more bicarbonate from the extracellular compartment than is added in the second half of treatment, a futile and unnecessary event. We propose that changes in dialysis prescription be studied in an attempt to moderate the initial rate of increase in blood [HCO3-] and the magnitude of the body buffer response. These new approaches include either a much lower bath [HCO3-] coupled with an increase in the bath acetate concentration or a stepwise increase in the bath [HCO3-] during treatment. In a subset of patients with low endogenous acid production, we propose reducing the bath [HCO3-] as the sole intervention.
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Kourtellidou SI, Ashby DR, Johansson LR. Oral sodium bicarbonate in people on haemodialysis: a randomised controlled trial. BMC Nephrol 2021; 22:346. [PMID: 34674667 PMCID: PMC8529780 DOI: 10.1186/s12882-021-02549-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 09/29/2021] [Indexed: 12/03/2022] Open
Abstract
Background Adverse events and mortality tend to cluster around dialysis sessions, potentially due to the impact of the saw-toothed profile of uraemic toxins such as potassium, peaking pre-dialysis and rapidly dropping during dialysis. Acidosis could be contributing to this harm by exacerbating a rise in potassium. The objectives of this study were to investigate the effects of oral bicarbonate treatment on reducing inter-dialytic potassium gain as well as other clinical consequences of preserving muscle mass and function and reducing intradialytic arrhythmia risk in people on haemodialysis. Methods Open-label randomised controlled trial in a single-centre (London, UK). Forty-three clinically stable adults on haemodialysis were recruited, with a 6 month average pre-dialysis serum bicarbonate level < 22 mmol/l and potassium > 4 mmol/l. Thirty-three participants completed the study. Oral sodium bicarbonate tablets titrated up to a maximum of 3 g bd (6 g total) in intervention group for 12 weeks versus no treatment in the control group. Outcomes compared intervention versus non-intervention phases in the treated group and equivalent time points in the control group: pre- and post-dialysis serum potassium; nutritional assessments: muscle mass and handgrip strength and electrocardiograms (ECGs) pre and post dialysis. Results Participants took an average of 3.7 ± 0.5 g sodium bicarbonate a day. In the intervention group, inter-dialytic potassium gain was reduced from 1.90 ± 0.60 to 1.69 ± 0.49 mmol/l (p = 0.032) and pre-dialysis potassium was reduced from 4.96 ± 0.62 to 4.79 ± 0.49 mmol/l without dietary change. Pre-dialysis bicarbonate increased from 18.15 ± 1.35 to 20.27 ± 1.88 mmol/l, however with an increase in blood pressure. Nutritionally, lean tissue mass was reduced in the controls suggesting less catabolism in the intervention group. There was no change in ECGs. Limitations are small sample size and unblinded study design lacking a placebo, with several participants failing to achieve the target of 22 mmol/l serum bicarbonate levels due mainly to tablet burden. Conclusion Oral sodium bicarbonate reduced bicarbonate loss and potassium gain in the inter-dialytic period, and may also preserve lean tissue mass. Trial registration The study was registered prospectively on 06/08/2015 with EU Clinical Trials Register EudraCT number 2015-001439-20.
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Affiliation(s)
- Stella I Kourtellidou
- Department of Nutrition and Dietetics, Hammersmith Hospital, Imperial College Healthcare NHS Trust, Du Cane Road W12 0HS, London, UK
| | - Damien R Ashby
- Renal and Transplant Centre, Hammersmith Hospital, Imperial College Healthcare NHS Trust, Du Cane Road W12 0HS, London, UK
| | - Lina R Johansson
- Department of Nutrition and Dietetics, Hammersmith Hospital, Imperial College Healthcare NHS Trust, Du Cane Road W12 0HS, London, UK.
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Bozikas A, Kiriakoutzik I, Petrou I, Touroutzis T, Kitoukidi E, Pisanidou P, Vakiani S, Georgilas N, Martika A, Pangidis P, Spaia S. Aiming for the optimal bicarbonate prescription for maintenance hemodialysis therapy in end-stage renal disease. Hemodial Int 2019; 23:173-180. [PMID: 30762289 DOI: 10.1111/hdi.12710] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 08/29/2018] [Accepted: 09/14/2018] [Indexed: 01/16/2023]
Abstract
INTRODUCTION Acidemia and alkalemia, as a result of gradual depletion of the body's buffers followed by rapid repletion during hemodialysis (HD), are linked to adverse consequences. We examined the acid-base status with dialysis bath of higher bicarbonate (HC03- ) concentration or standard HC03- bath plus oral HC03- supplementation. METHODS A total of 60 stable HD patients (pts) were evaluated according to their pre-dialysis acid-base status both before the first and the second session of the week dialyzed against standard base dialysate of 35 mmol/L. Those who presented predialysis HC03- <22 mmol/L (25 pts) were assigned to dialysis against bath of increased HC03- levels (37 mmol/L) for 2 weeks (period A) and subsequently to dialysis with the standard dialysate bath plus daily oral sodium bicarbonate at a dose of 5 g/day for 2 weeks (period B). Pre and post-dialysis acid-base status at each study period and relevant laboratory tests were recorded. FINDINGS Pre-dialysis acid-base values were similar between the first and the second dialysis session. Twenty-five points had pre-dialysis pH <7.35, while 42 (the younger ones) presented pre-dialysis HC03- <22 mmol/L. After dialysis session 18 pts had pH >7.45. Comparing the two study periods, interdialytic weight was similar, pre-dialysis HC03- levels were improved with oral bicarbonate, while post-dialysis HC03- were higher during period A. Three pts could not tolerate the symptoms of alkalemia during period A. DISCUSSION The impact of conventional HC03- concentrations of 35 mmol/L results in a considerable degree of pre-dialysis acidemia. Increasing the HC03- in bath results in more prominent post-dialysis alkalemia, however, it is not sufficient to maintain acid-base status during the interdialytic period. Oral bicarbonate supplement at a dose of 5 g/day (divided in three daily doses) results in a more balanced acid-base status, avoiding post-dialysis alkalemia.
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Affiliation(s)
- Andreas Bozikas
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Iliana Kiriakoutzik
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Ioannis Petrou
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Theodoros Touroutzis
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Eleni Kitoukidi
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Pinelopi Pisanidou
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Styliani Vakiani
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Nikolaos Georgilas
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Antigoni Martika
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Panagiotis Pangidis
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
| | - Sofia Spaia
- General Hospital of Thessaloniki "Agios Pavlos", Nephrology Department, Thessaloniki, Greece
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5
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Basile C, Rossi L, Lomonte C. Dialysate bicarbonate concentration: Too much of a good thing? Semin Dial 2018; 31:576-582. [PMID: 29885083 DOI: 10.1111/sdi.12716] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Acid-base equilibrium is a complex and vital system whose regulation is impaired in chronic kidney disease (CKD). Metabolic acidosis is a common complication of CKD. It is typically due to the accumulation of sulfate, phosphorus, and organic anions. Metabolic acidosis is correlated with several adverse outcomes, such as morbidity, hospitalization and mortality. In patients undergoing hemodialysis, acid-base homeostasis depends on many factors: net acid production, amount of alkali given by the dialysate bath, duration of interdialytic period, as well as residual diuresis, if any. Recent literature data suggest that the development of postdialysis metabolic alkalosis may contribute to adverse clinical outcomes. Unfortunately, no randomized studies exist about the effect of different dialysate bicarbonate concentrations on hard outcomes, such as mortality. Like everything else in dialysis, the quest for the "ideal" dialysate bicarbonate concentration is far from over. The Latin aphorism "ne quid nimis" ie "nothing in excess" (excess of neither acid nor base) probably best summarizes our current state of knowledge in this field. For the present, the clinician should understand that target values for predialysis serum bicarbonate concentrations have been established primarily based on observational studies and expert opinion. On the basis of this information, we should keep predialysis serum bicarbonate concentrations at least at 22 mEq/L. Furthermore, a specific focus should be addressed to the clinical and nutritional status of the major outliers on both the acid and alkaline sides of the curve.
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Affiliation(s)
- Carlo Basile
- Division of Nephrology, Clinical Research Branch, Miulli General Hospital, Acquaviva delle Fonti, Italy.,Associazione Nefrologica Gabriella Sebastio, Martina Franca, Italy
| | - Luigi Rossi
- Division of Nephrology, Miulli General Hospital, Acquaviva delle Fonti, Italy
| | - Carlo Lomonte
- Division of Nephrology, Miulli General Hospital, Acquaviva delle Fonti, Italy
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Sargent JA, Marano M, Marano S, Gennari FJ. Acid-base homeostasis during hemodialysis: New insights into the mystery of bicarbonate disappearance during treatment. Semin Dial 2018; 31:468-478. [PMID: 29813184 DOI: 10.1111/sdi.12714] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In patients receiving hemodialysis, it has long been recognized that much more bicarbonate is delivered during treatment than ultimately appears in the blood. To gain insight into this mystery, we developed a model that allows a quantitative analysis of the patient's response to rapid alkalinization during hemodialysis. Our model is unique in that it is based on the distribution of bicarbonate in the extracellular fluid and assesses its removal from this compartment by mobilization of protons (H+ ) from buffers and other sources. The model was used to analyze the pattern of rise in blood bicarbonate concentration ([HCO3- ]), calculated from measurements of pH and PCO2 , in patients receiving standard bicarbonate hemodialysis. Model analysis demonstrated two striking findings: (1) 35% of the bicarbonate added during hemodialysis was due to influx and metabolism of acetate, despite its low concentration in the bath solution, because of the rapidly collapsing gradient for bicarbonate influx. (2) Almost 90% of the bicarbonate delivered to the patients was neutralized by H+ generation. Virtually all the new H+ came from intracellular sources and included both buffering and organic acid production. The small amount of added bicarbonate retained in the extracellular fluid increased blood [HCO3- ], on average, by 6 mEq/L in our patients. Almost all this rise occurred during the first 2 hours. Thereafter, blood [HCO3- ] changed minimally and always remained less than bath [HCO3- ]. This lack of equilibrium was due to the continued production of organic acid. Release of H+ from buffers is a reversible physiological response, restoring body alkali stores. By contrast, organic acid production is an irreversible process during hemodialysis and is metabolically inefficient and potentially catabolic. Our analysis underscores the need to develop new approaches for alkali repletion during hemodialysis that minimize organic acid production.
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Affiliation(s)
| | - Marco Marano
- Hemodialysis Unit, Maria Rosaria Clinic, Pompeii, Naples, Italy
| | - Stefano Marano
- Department of Information and Electrical Engineering and Applied Mathematics, University of Salerno, Salerno, Fisciano, Italy
| | - F John Gennari
- University of Vermont College of Medicine, Burlington, VT, USA
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7
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Gennari FJ. Acid-base assessment of patients receiving hemodialysis. What are our management goals? Semin Dial 2018; 31:382-387. [PMID: 29495132 DOI: 10.1111/sdi.12682] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Acid-base assessment of patients receiving conventional hemodialysis (HD) has been based solely on predialysis serum [total CO2 ], and treatment is currently driven by the KDOQI guideline from 2000. This guideline was directed solely at minimizing metabolic acidosis and thereby improving bone and muscle metabolism. In 2000, no data were available to assess the effects of acid-base status on morbidity and mortality. Since then, new data have emerged from several large cohort studies about the association between variations in predialysis serum [total CO2 ], as well as blood pH, and morbidity and mortality risk. These studies have shown increased risk not only with very low predialysis [total CO2 ] values, but also with predialysis alkaline pH and very high predialysis serum [total CO2 ] values. At present, our major concern is not for patients with metabolic acidosis, but rather for the growing numbers of patients with metabolic alkalosis. This review discusses the controversies around assessing and treating acid-base status in HD patients, and recommends a practical approach based on the results of these recent studies. The new approach provides recommendations for patients both with very low and very high predialysis serum [total CO2 ] values.
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Affiliation(s)
- F John Gennari
- Department of Medicine, University of Vermont College of Medicine, Burlington, VT, USA
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8
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Tsubochi H, Shibano T, Endo S. Recommendations for perioperative management of lung cancer patients with comorbidities. Gen Thorac Cardiovasc Surg 2017; 66:71-80. [PMID: 29147917 PMCID: PMC5794844 DOI: 10.1007/s11748-017-0864-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/04/2017] [Indexed: 12/25/2022]
Abstract
Objectives To improve surgical outcomes, clinicians must provide optimal perioperative care for comorbidities identified as significant factors in risk models for patients undergoing lung cancer surgery. Methods We reviewed trends in perioperative care for idiopathic pulmonary fibrosis, cardiovascular diseases, and end-stage renal diseases in patients undergoing lung cancer surgery, as large clinical databases indicate that these comorbidities are significant risk factors for lung cancer surgery. Articles identified by keyword searches were included in the analysis. Results Significant predictive factors for acute exacerbation of idiopathic pulmonary fibrosis were identified. However, no effective perioperative care was identified for prevention of acute exacerbation of interstitial pneumonia. The timing of coronary revascularization and antithrombotic management for cardiovascular diseases are subjects of ongoing research, and acid–base balance is essential in the management of hemodialysis patients with end-stage renal diseases. Conclusions To improve surgical outcomes for lung cancer patients, future studies should continue to study optimal perioperative management of comorbidities.
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Affiliation(s)
- Hiroyoshi Tsubochi
- Department of Thoracic Surgery, Jichi Medical University, Tochigi, Japan
| | - Tomoki Shibano
- Department of Thoracic Surgery, Jichi Medical University, Tochigi, Japan
| | - Shunsuke Endo
- Department of Thoracic Surgery, Jichi Medical University, Tochigi, Japan.
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9
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Lew SQ, Kohn OF, Cheng YL, Kjellstrand CM, Ing TS. Three-Stream, Bicarbonate-Based Hemodialysis Solution Delivery System Revisited: With an Emphasis on Some Aspects of Acid-Base Principles. Artif Organs 2017; 41:509-518. [PMID: 28574225 DOI: 10.1111/aor.12947] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 02/22/2017] [Accepted: 03/03/2017] [Indexed: 11/28/2022]
Abstract
Hemodialysis patients can acquire buffer base (i.e., bicarbonate and buffer base equivalents of certain organic anions) from the acid and base concentrates of a three-stream, dual-concentrate, bicarbonate-based, dialysis solution delivery machine. The differences between dialysis fluid concentrate systems containing acetic acid versus sodium diacetate in the amount of potential buffering power were reviewed. Any organic anion such as acetate, citrate, or lactate (unless when combined with hydrogen) delivered to the body has the potential of being converted to bicarbonate. The prescribing physician aware of the role that organic anions in the concentrates can play in providing buffering power to the final dialysis fluid, will have a better knowledge of the amount of bicarbonate and bicarbonate precursors delivered to the patient.
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Affiliation(s)
- Susie Q Lew
- Department of Medicine, George Washington University, Washington, DC
| | - Orly F Kohn
- Department of Medicine, University of Chicago, Chicago, IL, USA
| | - Yuk-Lun Cheng
- Department of Medicine and ICU, Alice Ho Miu Ling Nethersole Hospital, Hong Kong, China
| | - Carl M Kjellstrand
- Department of Medicine, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Todd S Ing
- Department of Medicine, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
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10
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Sajgure AD, Dighe TA, Korpe JS, Bale CB, Sharma AO, Shinde NS, Goel AA, Mulay AV. The Relationship between Metabolic Acidosis and Nutritional Parameters in Patients on Hemodialysis. Indian J Nephrol 2017; 27:190-194. [PMID: 28553038 PMCID: PMC5434684 DOI: 10.4103/0971-4065.202404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The progressive loss of kidney function is accompanied by metabolic acidosis. The relationship between metabolic acidosis, nutritional status, and oral bicarbonate supplementation has not been assessed in the Indian chronic kidney disease (CKD) population who are on maintenance hemodialysis (MHD). This is a single-center prospective study conducted in the Western part of India. Thirty-five patients, who were receiving MHD were assessed for metabolic acidosis along with various nutritional parameters at the baseline and at the follow-up after 3 months, postcorrection of acidosis with oral sodium bicarbonate supplements. The relationship between the correction of metabolic acidosis with oral bicarbonate supplements and changes in dietary and various nutritional parameters were evaluated. Metabolic acidosis at the baseline evaluation was found in 62.86% cases of the cohort with a mean serum bicarbonate value of 20.18 ± 4.93 mmol/L. The correction of acidosis with increment in the mean dosage of oral sodium bicarbonate supplements from 0.69 ± 0.410 mmol/kg/day at baseline to 1.04 ± 0.612 mmol/kg/day, significantly reduced the prevalence of metabolic acidosis to 23.33% cases at the follow-up. Improvement in serum bicarbonate level showed significant dietary, anthropometric, and nutritional improvements in these patients. Hence, we conclude that correction of metabolic acidosis with optimal oral bicarbonate supplementation plays a pivotal role in the treatment of malnourished CKD patients on MHD.
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Affiliation(s)
- A D Sajgure
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - T A Dighe
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - J S Korpe
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - C B Bale
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - A O Sharma
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - N S Shinde
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - A A Goel
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
| | - A V Mulay
- Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, Maharashtra, India
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11
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Panesar M, Shah N, Vaqar S, Ivaturi K, Gudleski G, Muscarella M, Lambert J, Su W, Murray B. Changes in Serum Bicarbonate Levels Caused by Acetate-Containing Bicarbonate-Buffered Hemodialysis Solution: An Observational Prospective Cohort Study. Ther Apher Dial 2017; 21:157-165. [DOI: 10.1111/1744-9987.12510] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 09/20/2016] [Accepted: 10/18/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Mandip Panesar
- The Regional Center of Excellence for Transplantation & Kidney Care at Erie County Medical Center; Buffalo New York
- Department of Medicine, Jacobs School of Medicine; University at Buffalo; Buffalo New York
| | - Neal Shah
- Department of Medicine, Jacobs School of Medicine; University at Buffalo; Buffalo New York
| | - Sarosh Vaqar
- Department of Medicine, Jacobs School of Medicine; University at Buffalo; Buffalo New York
| | - Kaushik Ivaturi
- Department of Medicine, Jacobs School of Medicine; University at Buffalo; Buffalo New York
| | - Gregory Gudleski
- Department of Medicine, Jacobs School of Medicine; Statistics and Data Management Lab; Buffalo New York USA
| | - Mary Muscarella
- The Regional Center of Excellence for Transplantation & Kidney Care at Erie County Medical Center; Buffalo New York
| | - Judy Lambert
- The Regional Center of Excellence for Transplantation & Kidney Care at Erie County Medical Center; Buffalo New York
| | - Winnie Su
- The Regional Center of Excellence for Transplantation & Kidney Care at Erie County Medical Center; Buffalo New York
- Department of Medicine, Jacobs School of Medicine; University at Buffalo; Buffalo New York
| | - Brian Murray
- The Regional Center of Excellence for Transplantation & Kidney Care at Erie County Medical Center; Buffalo New York
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12
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Abstract
The optimal approach to managing acid-base balance is less well defined for patients receiving hemodialysis than for those receiving peritoneal dialysis. Interventional studies in hemodialysis have been limited and inconsistent in their findings, whereas more compelling data are available from interventional studies in peritoneal dialysis. Both high and low serum bicarbonate levels associate with an increased risk of mortality in patients receiving hemodialysis, but high values are a marker for poor nutrition and comorbidity and are often highly variable from month to month. Measurement of pH would likely provide useful additional data. Concern has arisen regarding high-bicarbonate dialysate and dialysis-induced alkalemia, but whether these truly cause harm remains to be determined. The available evidence is insufficient for determining the optimal target for therapy at this time.
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Affiliation(s)
- Matthew K Abramowitz
- Division of Nephrology, Department of Medicine, and
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York
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13
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Yamamoto T, Shoji S, Yamakawa T, Wada A, Suzuki K, Iseki K, Tsubakihara Y. Predialysis and Postdialysis pH and Bicarbonate and Risk of All-Cause and Cardiovascular Mortality in Long-term Hemodialysis Patients. Am J Kidney Dis 2015; 66:469-78. [PMID: 26015276 DOI: 10.1053/j.ajkd.2015.04.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 04/05/2015] [Indexed: 11/11/2022]
Abstract
BACKGROUND To date, very few studies have been carried out on the associations of pre- and postdialysis acid-base parameters with mortality in hemodialysis patients. STUDY DESIGN An observational study including cross-sectional and 1-year analyses. SETTING & PARTICIPANTS Data from the renal registry of the Japanese Society of Dialysis Therapy (2008-2009), including 15,132 dialysis patients 16 years or older. PREDICTOR Predialysis pH<7.30, 7.30 to 7.34 (reference), 7.35 to 7.39, or ≥7.40 (1,550, 4,802, 6,023, and 2,757 patients, respectively); predialysis bicarbonate level < 18.0, 18.0 to 21.9 (reference), 22.0 to 25.9, or ≥26.0 mEq/L (2,724, 7,851, 4,023, and 534 patients, respectively); postdialysis pH<7.40, 7.40 to 7.44, 7.45 to 7.49 (reference), or ≥7.50 (2,114, 5,331, 4,975, and 2,712 patients, respectively); and postdialysis bicarbonate level < 24.0, 24.0 to 25.9, 26.0 to 27.9 (reference), or ≥28.0 mEq/L (5,087, 4,330, 3,451, and 2,264 patients, respectively). OUTCOMES All-cause and cardiovascular (CV) mortality during the 1-year follow-up. MEASUREMENTS HRs were estimated using unadjusted models and models adjusted for age, sex, dialysis vintage, history of CV disease, diabetes, weight gain ratio, body mass index, calcium-phosphorus product, serum albumin level, serum total cholesterol level, blood hemoglobin level, single-pool Kt/V, and normalized protein catabolic rate. RESULTS Of 15,132 patients, during follow-up, 1,042 died of all causes, including 408 CV deaths. In the adjusted analysis for all-cause mortality, HRs compared to the reference group were significantly higher in patients with predialysis pH≥7.40 (HR, 1.36; 95% CI, 1.13-1.65) and postdialysis pH<7.40 (HR, 1.22; 95% CI, 1.00-1.49). Predialysis pH≥7.40 was also associated with higher risk of CV mortality (HR, 1.34; 95% CI, 1.01-1.79). No association of pre- or postdialysis bicarbonate level with all-cause and CV mortality was observed. LIMITATIONS Single measurements of acid-base parameters, short duration of follow-up, small number of CV deaths. CONCLUSIONS Predialysis pH≥7.40 was associated with significantly elevated risk of all-cause and CV mortality. However, pre- and postdialysis bicarbonate levels were not associated with all-cause and CV mortality. Predialysis pH may be the most appropriate reference for accurate correction of metabolic acidosis in dialysis patients.
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Affiliation(s)
| | | | | | - Atsushi Wada
- Committee of Renal Data Registry of the Japanese Society for Dialysis Therapy, Tokyo, Japan
| | - Kazuyuki Suzuki
- Committee of Renal Data Registry of the Japanese Society for Dialysis Therapy, Tokyo, Japan
| | - Kunitoshi Iseki
- Committee of Renal Data Registry of the Japanese Society for Dialysis Therapy, Tokyo, Japan
| | - Yoshiharu Tsubakihara
- Committee of Renal Data Registry of the Japanese Society for Dialysis Therapy, Tokyo, Japan
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Saikumar JH, Kovesdy CP. Bicarbonate Therapy in End-Stage Renal Disease: Current Practice Trends and Implications. Semin Dial 2015; 28:370-6. [PMID: 25845518 DOI: 10.1111/sdi.12373] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Management of metabolic acidosis covers the entire spectrum from oral bicarbonate therapy and dietary modifications in chronic kidney disease to delivery of high doses of bicarbonate-based dialysate during maintenance haemodialysis (MHD). Due to the gradual depletion of the body's buffers and rapid repletion during MHD, many potential problems arise as a result of our current treatment paradigms. Several studies have given rise to conflicting data about the adverse effects of our current practice patterns in MHD. In this review, we will describe the pathophysiology and consequences of metabolic acidosis and its therapy in CKD and ESRD, and discuss current evidence supporting a more individualized approach for bicarbonate therapy in MHD.
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Affiliation(s)
- Jagannath H Saikumar
- Division of Nephrology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Csaba P Kovesdy
- Division of Nephrology, University of Tennessee Health Science Center, Memphis, Tennessee.,Nephrology Section, Memphis VA Medical Center, Memphis, Tennessee
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Lisawat P, Gennari FJ. Approach to the Hemodialysis Patient With an Abnormal Serum Bicarbonate Concentration. Am J Kidney Dis 2014; 64:151-5. [DOI: 10.1053/j.ajkd.2013.12.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 12/24/2013] [Indexed: 11/11/2022]
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Tentori F, Karaboyas A, Robinson BM, Morgenstern H, Zhang J, Sen A, Ikizler TA, Rayner H, Fissell RB, Vanholder R, Tomo T, Port FK. Association of dialysate bicarbonate concentration with mortality in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Am J Kidney Dis 2013; 62:738-46. [PMID: 23707043 PMCID: PMC3832240 DOI: 10.1053/j.ajkd.2013.03.035] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 03/21/2013] [Indexed: 11/11/2022]
Abstract
BACKGROUND Most hemodialysis patients worldwide are treated with bicarbonate dialysis using sodium bicarbonate as the base. Few studies have assessed outcomes of patients treated with different dialysate bicarbonate levels, and the optimal concentration remains uncertain. STUDY DESIGN The Dialysis Outcomes and Practice Patterns Study (DOPPS) is an international prospective cohort study. SETTING & PARTICIPANTS This study included 17,031 patients receiving thrice-weekly in-center hemodialysis from 11 DOPPS countries (2002-2011). PREDICTOR Dialysate bicarbonate concentration. OUTCOMES All-cause and cause-specific mortality and first hospitalization, using Cox regression to estimate the effects of dialysate bicarbonate concentration, adjusting for potential confounders. MEASUREMENTS Demographics, comorbid conditions, laboratory values, and prescriptions were abstracted from medical records. RESULTS Mean dialysate bicarbonate concentration was 35.5 ± 2.7 (SD) mEq/L, ranging from 32.2 ± 2.3 mEq/L in Germany to 37.0 ± 2.6 mEq/L in the United States. Prescription of high dialysate bicarbonate concentration (≥38 mEq/L) was most common in the United States (45% of patients). Approximately 50% of DOPPS facilities used a single dialysate bicarbonate concentration. 3,913 patients (23%) died during follow-up. Dialysate bicarbonate concentration was associated positively with mortality (adjusted HR, 1.08 per 4 mEq/L higher [95% CI, 1.01-1.15]; HR for dialysate bicarbonate ≥38 vs 33-37 mEq/L, 1.07 [95% CI, 0.97-1.19]). Results were consistent across levels of pre-dialysis session serum bicarbonate and between facilities that used a single dialysate bicarbonate concentration and those that prescribed different concentrations to individual patients. The association of dialysis bicarbonate concentration with mortality was stronger in patients with longer dialysis vintage. LIMITATIONS Due to the observational nature of the present study, we cannot rule out that the reported associations may be biased by unmeasured confounders. CONCLUSIONS High dialysate bicarbonate concentrations, especially prolonged exposure, may contribute to adverse outcomes, likely through the development of postdialysis metabolic alkalosis. Additional studies are warranted to identify the optimal dialysate bicarbonate concentration.
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Affiliation(s)
- Francesca Tentori
- Arbor Research Collaborative for Health, Ann Arbor, MI; Vanderbilt University Medical Center, Nashville, TN.
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Thet Z, Win AK, Pedagogos E, Beavis J, Crikis S, Nelson C. Differential effects of phosphate binders on pre-dialysis serum bicarbonate in end-stage kidney disease patients on maintenance haemodialysis. BMC Nephrol 2013; 14:205. [PMID: 24079654 PMCID: PMC3850673 DOI: 10.1186/1471-2369-14-205] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 09/25/2013] [Indexed: 11/10/2022] Open
Abstract
Background Phosphate binders’ constituents have alkalotic or acidotic properties and may contribute to acid base balance in haemodialysis patients. This study aimed to investigate the differential effects of phosphate binders on pre-dialysis serum bicarbonate in End Stage Kidney Disease patients on maintenance haemodialysis. Methods Stable out-patients having satellite haemodialysis for at least 3 months were retrospectively studied for 18 months, excluding those with other medical causes for metabolic acidosis. Blood results were censored for inpatient episodes, at the time of death, renal transplant or dialysis modality change. Multivariable multilevel mixed-effects linear regression was used and five groups of phosphate binders were compared: Group A(Calcium (Ca) and/or Aluminium (Al) binders); B(Sevelamer hydrochloride (SH) alone); C(lanthanum carbonate (LC) alone); D(SH and Ca/Al), E(LC and Ca/Al). Results Of 320 patients, 292 were eligible for analysis with a mean follow-up of 15.54 (standard deviation, SD 3.98) months. Similar mean pre-dialysis serum levels of bicarbonate were observed at all 6 month-interval analyses. At 18th months, observed mean serum bicarbonate levels in mmol/L were Group B: 21.58 (SD 2.82, P<0.001), C: 23.29 (SD 2.80, P=0.02), D: 21.56 (SD 3.00, P<0.001), and E: 21.29 (SD 3.62, P=0.92) compared with Group A: 22.98 (SD 2.77). Mean serum bicarbonate was related to total SH dose in mmol/L: 22.34 (SD 2.56) for SH <2.5 g/day, 21.61 (SD 2.62) for SH 2.5-4.8 g/day, 21.04 (SD 3.31) for SH >4.8 g/day compared with 22.85 (SD 2.91) for non-users; P-trend<0.001. Conclusions Phosphate binders’ constituents may contribute to/protect against a predisposition to pre-dialysis metabolic acidosis. This may be dose dependant in patients taking Sevelamer Hydrochloride.
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Affiliation(s)
- Zaw Thet
- Department of Nephrology, Western Health, Melbourne, Victoria, Australia.
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Koda R, Imanishi Y, Yoshino A, Kawamoto S, Kazama JJ, Narita I, Takeda T. Persistent metabolic acidosis in a hemodialyzed patient with short bowel syndrome. Intern Med 2013; 52:1379-82. [PMID: 23774551 DOI: 10.2169/internalmedicine.52.0029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Short bowel syndrome (SBS) is characterized by a malabsorptive state. It is conceivable that the coexistence of SBS and end-stage renal disease can lead to severe metabolic acidosis; however, such a condition has rarely been documented. We herein describe the case of a 64-year-old man with SBS who required maintenance hemodialysis. Persistent metabolic acidosis and mineral and bone disorders should be of particular concern in hemodialyzed patients with SBS.
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Affiliation(s)
- Ryo Koda
- Department of Nephrology, Dokkyo Medical University Koshigaya Hospital, Japan.
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John Gennari F. Very Low and High Predialysis Serum Bicarbonate Levels are Risk Factors for Mortality: What are the Appropriate Interventions? Semin Dial 2010; 23:253-7. [DOI: 10.1111/j.1525-139x.2010.00737.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gabutti L, Bianchi G, Soldini D, Marone C, Burnier M. Haemodynamic consequences of changing bicarbonate and calcium concentrations in haemodialysis fluids. Nephrol Dial Transplant 2008; 24:973-81. [PMID: 18842671 PMCID: PMC2644633 DOI: 10.1093/ndt/gfn541] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Background. In a previous study we demonstrated that mild metabolic alkalosis resulting from standard bicarbonate haemodialysis induces hypotension. In this study, we have further investigated the changes in systemic haemodynamics induced by bicarbonate and calcium, using non-invasive procedures. Methods. In a randomized controlled trial with a single-blind, crossover design, we sequentially changed the dialysate bicarbonate and calcium concentrations (between 26 and 35 mmol/l for bicarbonate and either 1.25 or 1.50 mmol/l for calcium). Twenty-one patients were enrolled for a total of 756 dialysis sessions. Systemic haemodynamics was evaluated using pulse wave analysers. Bioimpedance and BNP were used to compare the fluid status pattern. Results. The haemodynamic parameters and the pre-dialysis BNP using either a high calcium or bicarbonate concentration were as follows: systolic blood pressure (+5.6 and −4.7 mmHg; P < 0.05 for both), stroke volume (+12.3 and +5.2 ml; P < 0.05 and ns), peripheral resistances (−190 and −171 dyne s cm−5; P < 0.05 for both), central augmentation index (+1.1% and −2.9%; ns and P < 0.05) and BNP (−5 and −170 ng/l; ns and P < 0.05). The need of staff intervention was similar in all modalities. Conclusions. Both high bicarbonate and calcium concentrations in the dialysate improve the haemodynamic pattern during dialysis. Bicarbonate reduces arterial stiffness and ameliorates the heart tolerance for volume overload in the interdialytic phase, whereas calcium directly increases stroke volume. The slight hypotensive effect of alkalaemia should motivate a probative reduction of bicarbonate concentration in dialysis fluid for haemodynamic reasons, only in the event of failure of classical tools to prevent intradialytic hypotension.
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Affiliation(s)
- Luca Gabutti
- Division of Nephrology, Ospedale la Carità, Locarno, Switzerland.
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Alkalemia during continuous renal replacement therapy and mortality in critically ill patients. Crit Care Med 2008; 36:1513-7. [PMID: 18434895 DOI: 10.1097/ccm.0b013e318170a2f5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Acid-base disorders are common in critically ill patients. Once continuous renal replacement therapy (CRRT) is initiated, it becomes a major determinant of acid-base status. We hypothesized that therapy-induced alkalemia and alkalosis is associated with increased mortality. PATIENTS The CCF-ARF Registry (1995-01) was used to identify 405 patients supported with bicarbonate based continuous hemodialysis. Proportion of days with an elevated pH to the number of days with normal pH was used to assess the association of alkalemia and the number of days with alkalemia, and mortality. Multivariable analyses were used to adjust for days with acidosis, and other relevant covariates. MAIN RESULTS Serum bicarbonate and pH levels plateau after 48 hrs of CRRT. Study subjects had on average 1.5 +/- 2.9 days where pH was greater than 7.45, and .4 days where serum bicarbonate level was greater than 28 mmol/L, during a median of 9 days of CRRT. Daily dialysis dose was inversely associated with the number of days with a low serum bicarbonate level, but was not associated with increased frequency of an elevated pH or serum bicarbonate level. Increasing proportion of days with elevated pH or serum bicarbonate was not associated with increased mortality in multivariable analysis. CONCLUSIONS Alkalemia and alkalosis occur frequently during CRRT, but they are not associated with increased mortality. Persistent acidosis and acidemia while on CRRT was a strong predictor of poor outcome.
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Noh US, Yi JH, Han SW, Kim HJ. Varying Dialysate Bicarbonate Concentrations in Maintenance Hemodialysis Patients Affect Post-dialysis Alkalosis but not Pre-dialysis Acidosis. Electrolyte Blood Press 2007; 5:95-101. [PMID: 24459507 PMCID: PMC3894521 DOI: 10.5049/ebp.2007.5.2.95] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Accepted: 10/01/2007] [Indexed: 12/04/2022] Open
Abstract
This study aimed to assess the effects of different dialysate bicarbonate concentrations in correcting acid-base imbalance in 53 stable hemodialysis patients in a university-hemodialysis unit. Three different bicarbonate concentrations were assigned, i.e. 25 mEq/L in 10, 30 mEq/L in 30, and 35 mEq/L in 13 patients. Blood gas analyses from arterial line blood samples before and after dialysis in the mid-week were performed for the determination of pH and serum bicarbonate (HCO3-) concentration. The mean values of predialysis arterial HCO3- were mildly acidotic in all 3 groups, but not significantly different among them, whereas those of post-dialysis arterial HCO3- were alkalotic, especially in the group of 35 mEq/L as compared with the other two groups. The mean blood pH was not significantly different among the 3 groups. As expected, there was a positive correlation between pre-dialysis pH and post-dialysis pH (r=0.45, p=0.001), and pre-dialysis HCO3- and post-dialysis HCO3- (r=0.58, p=0.000), but with a negative correlation between pre-dialysis HCO3- and the increment of intradialytic HCO3- following hemodialysis (r=-0.46, p=0.001). In conclusion, this study shows that the impact of conventional dialysate bicarbonate concentrations ranging from 25 to 35 mEq/L is not quite different on the mild degree of predialysis acidemia, but the degree of postdialysis alkalemia is more prominent in higher bicarbonate concentrations. Base supply by hemodialysis alone does not seem to be the main factor to determine the predialysis acidosis in end-stage renal disease patients on chronic maintenance hemodialysis.
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Affiliation(s)
- U-Seok Noh
- Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea
| | - Joo-Hark Yi
- Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea
| | - Sang-Woong Han
- Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea
| | - Ho-Jung Kim
- Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea
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Sam R, Vaseemuddin M, Leong WH, Rogers BE, Kjellstrand CM, Ing TS. Composition and clinical use of hemodialysates. Hemodial Int 2006; 10:15-28. [PMID: 16441823 DOI: 10.1111/j.1542-4758.2006.01170.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A thorough knowledge and understanding of the principles underlying the preparation and the clinical application of hemodialysates can help us provide exemplary patient care to individuals having end-stage renal disease. It is prudent to be conversant with the following: (a) how each ingredient in a dialysate works, (b) the clinical circumstances under which the concentration of an ingredient can be altered, and (c) the special situations in which unconventional ingredients can be introduced into a dialysate. The potential to enrich dialysates with appropriate ingredients (such as iron compounds) is limited only by the boundaries of our imagination.
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Affiliation(s)
- Ramin Sam
- Department of Medicine, John H. Stroger Hospital of Cook County and School of Medicine, University of Illinois at Chicago, USA
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Apsner R, Buchmayer H, Gruber D, Sunder-Plassmann G. Citrate for long-term hemodialysis: prospective study of 1,009 consecutive high-flux treatments in 59 patients. Am J Kidney Dis 2005; 45:557-64. [PMID: 15754278 DOI: 10.1053/j.ajkd.2004.12.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Regional citrate anticoagulation during hemodialysis is performed in selected patients at highly specialized units. We postulated that routine use of citrate at a long-term dialysis ward is safe and efficient. METHODS During a 2-year period, we studied 1,009 consecutive citrate-anticoagulated high-flux hemodialysis treatments performed in 59 patients at our long-term dialysis ward. We used a simple citrate infusion protocol, calcium-free dialysate, and intravenous calcium substitution. Simple and clear algorithms allowed adjustments of the calcium substitution rate and dialysate settings by the attending nurse. Adverse events; indications for citrate anticoagulation; clotting; technical data; blood ionized calcium, sodium, and potassium levels; and acid-base homeostasis were analyzed prospectively. RESULTS Of the treatments, 99.6% were accomplished successfully. Two adverse events were attributed to citrate use. Overall, ionized calcium levels were stable during the procedures and electrolyte and acid-base balances were well controlled. The use of central venous catheters for dialysis was associated with paradoxical behavior of ionized calcium levels (increasing blood ionized calcium levels despite decreased calcium infusion). Anticoagulation was excellent. CONCLUSION Routine use of citrate anticoagulation in the setting of a long-term hemodialysis ward is safe and efficient. Measured ionized calcium levels should be interpreted with care if central venous catheters are used for vascular access because they could be biased by recirculation.
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Affiliation(s)
- Robert Apsner
- Department of Medicine III, Division of Nephrology and Dialysis, University of Vienna, Vienna, Austria.
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Gabutti L, Ross V, Duchini F, Mombelli G, Marone C. Does bicarbonate transfer have relevant hemodynamic consequences in standard hemodialysis? Blood Purif 2005; 23:365-72. [PMID: 16088104 DOI: 10.1159/000087193] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2004] [Accepted: 05/02/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND In a previous study we demonstrated that mild metabolic alkalosis resulting from standard bicarbonate hemodialysis induces hypotension. This study aimed to compare hemodynamic consequences of either a decrease in the dialysate bicarbonate from 32 to 26 mmol/l or an increase in the dialysate calcium of 0.25 mmol/l and to verify whether the calcium shift secondary to alkalemia explains the consequences on blood pressure. METHODS In this randomized controlled trial with a single-blind, cross-over design, we used dialysis liquids with two different bicarbonate (32 mmol/l in modalities A and C, and 26 mmol/l in modality B) and calcium (1.25 mmol/l in modalities A and B, and 1.50 mmol/l in modality C) concentrations, and in 27 patients, 243 dialysis sessions, compared blood pressure, heart rate and the incidence of hypotension. RESULTS No significant differences were seen between A and B while an increase in systolic and diastolic blood pressures and a decrease in the incidence of hypotension (10.5 vs. 1.2%, p < 0.05) were documented in C. The subgroup of patients who with A showed a lower mean systolic blood pressure received more angiotensin-converting enzyme inhibitors or angiotensin II type-1 receptor blockers (36 vs. 0%, p<0.05) and in C showed a less important increase in systolic and diastolic pressures, but the incidence of hypotensive episodes between A and B was not significantly different (9.1 vs. 15.1%). CONCLUSIONS In the present study it was not possible to demonstrate hemo dynamic instability associated with mild metabolic alkalosis. Even in the subgroup showing a lower blood pressure with a higher dialysate bicarbonate, significant hemodynamic or clinical consequences were not noticed. The calcium shift (0.05 mmol/l) related to alkalemia would justify a mean decrease in systolic blood pressure of only about 1 mm Hg.
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Affiliation(s)
- Luca Gabutti
- Department of Nephrology, Ospedale la Carità, Locarno, Switzerland.
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Heguilén RM, Sciurano C, Bellusci AD, Fried P, Mittelman G, Rosa Diez G, Bernasconi AR. The faster potassium-lowering effect of high dialysate bicarbonate concentrations in chronic haemodialysis patients. Nephrol Dial Transplant 2005; 20:591-7. [PMID: 15687112 DOI: 10.1093/ndt/gfh661] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Hyperkalaemia is common in patients with advanced renal disease. In this double-blind, randomized, three-sequence, crossover study, we compared the effect of three dialysate bicarbonate concentrations ([HCO3-]) on the kinetics of serum potassium (K+) reduction during a conventional haemodialysis (HD) session in chronic HD patients. METHODS We studied eight stable HD patients. The choice of dialysate [HCO3-] followed a previously assigned treatment protocol and the [HCO3-] used were low bicarbonate (LB; 27 mmol/l), standard bicarbonate (SB; 35 mmol/l) and high bicarbonate (HB; 39 mmol/l). Polysulphone dialysers and automated machines provided blood flow rates of 300 ml/min and dialysis flow rates of 500 ml/min for each HD session. Blood samples were drawn at 0 (baseline), 15, 30, 60 and 240 min from the arterial extracorporeal line to assess blood gases and serum electrolytes. In three of the eight patients, we measured serum K+ 1 h post-dialysis as well as K+ removal by the dialysis. The same procedures were followed until the completion of the three arms of the study, with a 1 week interval between each experimental arm. RESULTS Serum K+ decreased from 5.4+/-0.26 (baseline) to 4.96+/-0.20, 4.90+/-0.19, 4.68+/-0.13 and 4.24+/-0.15 mmol/l at 15, 30, 60 and 240 min, respectively, with LB; from 5.38+/-0.21 to 5.01+/-0.23, 4.70+/-0.25, 4.3+/-0.15 and 3.8+/-0.19 mmol/l, respectively, with SB; and from 5.45+/-0.25 to 4.79+/-0.17, 4.48+/-0.17, 3.86+/-0.16 and 3.34+/-0.11 mmol/l, respectively, with HB (P<0.05 for high vs standard and low [HCO3-] at 60 and 240 min). The decrease in serum K+ correlated with the rise in serum [HCO3-] in all but LB (P<0.05). Potassium rebound was 3.9+/-10.2%, 5.2+/-6.6% and 8.9+/-4.9% for LB, SB and HB dialysates, respectively (P=NS), while total K+ removal (mmol/dialysis) was 116.4+/-21.6 for LB, 73.2+/-12.8 for SB and 80.9+/-15.4 for HB (P=NS). CONCLUSIONS High dialysate [HCO3-] was associated with a faster decrease in serum K+. Our results strongly suggest that this reduction was due to the enhanced shifting of K+ from the extracellular to the intracellular fluid compartment rather than its removal by dialysis. This finding could have an impact for those patients with life-threatening pre-HD hyperkalaemia.
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Affiliation(s)
- Ricardo M Heguilén
- Unidad de Nefrología, Hospital Juan A. Fernández, Paraguay 5259 Piso 3 Apt A, C1425BTG Buenos Aires, Argentina.
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Tzanatos H, Dalamangas A, Retsa K, Kapetanaki A, Agroyannis B. Relation of Interdialytic Water Retention with Apparent Bicarbonate Space, HCO 3−, and pH in Hemodialyzed Uremic Patients. Ren Fail 2005. [DOI: 10.1081/jdi-49542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Locatelli F, Covic A, Chazot C, Leunissen K, Luño J, Yaqoob M. Optimal composition of the dialysate, with emphasis on its influence on blood pressure. Nephrol Dial Transplant 2004; 19:785-96. [PMID: 15031331 DOI: 10.1093/ndt/gfh102] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
UNLABELLED Introduction. From the beginning of the dialysis era, the most appropriate composition of the dialysate has been one of the central topics in the delivery of dialysis treatment. METHODS A discussion is employed to achieve a consensus on key points relating to the composition of the dialysate, focusing on the relationships with blood pressure behaviour. RESULTS Sodium balance is the cornerstone of intra-dialysis cardiovascular stability and good inter-dialysis blood pressure control. Hypernatric dialysis carries the risk of positive sodium balance, with the consequent possibility of the worsening sense of thirst and hypertension. Conversely, hyponatric dialysis may lead to negative sodium balance, with the possibility of intra-dialysis cardiovascular instability and 'disequilibrium' symptoms including fatigue, muscle cramps and headache. The goal is to remove with dialysis the exact amount of sodium that has accumulated in the inter-dialysis interval. The conductivity kinetic model is applicable on-line at each dialysis session and has been proved to be able to improve intra-dialytic cardiovascular stability in hypotension-prone patients. Therefore, it should be regarded as a promising tool to be implemented in everyday clinical practice. Serum potassium concentration and variations during dialysis treatment certainly play a role in the genesis of cardiac arrhythmia. Potassium profiling, with a constant gradient between plasma and dialysate, should be implemented in clinical practice to minimize the arrhythmogenic potential of dialysis. Calcium plays a role both in myocardial contractility and in peripheral vascular resistance. Therefore, an increase in dialysate calcium concentration may be useful in cardiac compromised hypotension-prone patients. Acid-buffering by means of base supplementation is one of the major roles of dialysis. Bicarbonate concentration in the dialysate should be personalized in order to reach a midweek pre-dialysis serum bicarbonate concentration of 22 mmol/l. The role of convective dialysis techniques in cardiovascular stability is still under debate. It has been demonstrated that dialysate temperature and sodium balance play a role and this should be taken into account. Whether removal of vasoactive, middle-sized compounds by convection plays an independent role in improving cardiovascular stability is still uncertain. CONCLUSIONS The prescription of dialysis fluid is moving from a pre-fixed, standard dialysate solution to individualization of electrolyte and buffer composition, not only during the dialysis session, but also within the same session (profiling) in order to provide patients with an optimal blood purification coupled with a high degree of tolerability.
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Affiliation(s)
- Francesco Locatelli
- Department of Nephrology and Dialysis, Ospedale A. Manzoni, Via Dell'Eremo 11, 23900 Lecco, Italy.
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Kraut JA, Madias NE. Opinion: What Unique Acid-Base Considerations Exist in Dialysis Patients? Semin Dial 2004. [DOI: 10.1111/j.0894-0959.2004.17344.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Wiederkehr MR, Kalogiros J, Krapf R. Correction of metabolic acidosis improves thyroid and growth hormone axes in haemodialysis patients. Nephrol Dial Transplant 2004; 19:1190-7. [PMID: 14993483 DOI: 10.1093/ndt/gfh096] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Chronic metabolic acidosis (CMA) in normal adults results in complex endocrine and metabolic alterations including growth hormone (GH) insensitivity, hypothyroidism, hyperglucocorticoidism, hypoalbuminaemia and loss of protein stores. Similar alterations occur in chronic renal failure, a prototypical state of CMA. We evaluated whether metabolic acidosis contributes to the endocrine and metabolic alterations characteristic of end-stage renal disease. METHODS We treated 14 chronic haemodialysis patients with daily oral Na-citrate for 4 weeks, yielding a steady-state pre-dialytic plasma bicarbonate concentration of 26.7 mmol/l, followed by 4 weeks of equimolar Na-chloride, yielding a steady-state pre-dialytic plasma bicarbonate of 20.2 mmol/l. RESULTS Blood pressure, body weight and dialysis adequacy were equivalent in the two protocols. Na-citrate treatment corrected CMA, improved GH insensitivity, increased and normalized plasma free T(3) concentration, and improved plasma albumin. Correction of CMA had no significant effect on measured cytokines (interleukin-1 beta and -6, tumour necrosis factor-alpha) or acute phase reactants (C-reactive protein, serum amyloid A, alpha(2)-macroglobulin). CONCLUSION CMA contributes to the derangements of the growth and thyroid hormone axes and to hypoalbuminaemia, but is not a modulator of systemic inflammation in dialysis patients. Correcting CMA may improve nutritional and metabolic parameters and thus lower morbidity and mortality.
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Affiliation(s)
- Michael R Wiederkehr
- Department of Internal Medicine, University Hospital Bruderholz, Basel, Switzerland.
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Agroyannis B, Fourtounas C, Tzanatos H, Kapetanaki A, Dalamangas A, Vlahakos DV. Pre-HD dilution acidosis, without post-HD contraction alkalosis in uremic patients. Int J Artif Organs 2003; 26:135-8. [PMID: 12653347 DOI: 10.1177/039139880302600207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to verify if the degree of pre-HD acidosis and its correction post-HD is related to body fluid expansion during the interdialytic period. Twelve uremic patients without major problems, with stable hematocrit, with regular and similar HD-session characteristics, but widely varying amounts of body fluid expansion in the interdialytic period were included. Blood samples were collected from arterial line pre- and post-HD, anaerobically in heparinized syringes, for determination of HCO3-, pH and PaCO2 (radiometer Copenhagen ABL 300 Acid-Base Laboratory), in two similar HD-sessions for each patient (12 patients, 24 HD-sessions). The percentage (%) of body weight gain in the interdialytic period was also estimated. For each patient, the mean value of parameters studied in the two HD-sessions was used for the evaluation of findings. According to mean values (+/-SD) of HCO3-, pH and PaCO2 Pre-HD (18.26+/-1.99 mmol/L, 7.31+/-0.03, 36.27+/-2.5 mmHg respectively) and post-HD (26.37+/-1.7, 7.43+/-0.03, 38.43+/-2.10 respectively) patients are acidotic pre-HD and slightly alkalemic post-HD. Correlation between the percentage (%) of interdialytic body weight gain (IBWG) and the values of HCO3-, pH and PaCO2, Pre-HD (r=-0.814, p<0.001; r=-0.931, p<0.001; r=0, 100 NS; respectively) and post-HD (r=-0.958, p<0.001; r=-0.937, p<0.001; r=-0.504 NS; respectively) indicates a significant and negative relationship of IBWG% with HCO3- and pH pre- and post-HD, but not with PCO2. In conclusion, the negative relationship of IBWG% with HCO3- and pH pre- and post-HD indicates that the body fluid expansion during the interdialytic period contributes to a dilutional acidosis pre-HD, but not to a contraction alkalosis post-HD, by the elimination of fluid during the HD-session.
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Affiliation(s)
- B Agroyannis
- Department of Nephrology, Aretaieion University Hospital, Athens, Greece
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Unver B, Sunder-Plassmann G, Hörl WH, Apsner R. Long-term citrate anticoagulation for high-flux haemodialysis in a patient with heparin-induced thrombocytopenia type II. ACTA MEDICA AUSTRIACA 2002; 29:146-8. [PMID: 12424942 DOI: 10.1046/j.1563-2571.2002.02019.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
For the first time, long-term use of regional citrate anticoagulation for high-flux haemodialysis is reported in a patient with heparin-induced thrombocytopenia type II. A simple, flow-independent, citrate infusion protocol allowed efficient anticoagulation. Excellent solute removal, indicated by KT/V values of 1.52 to 1.98, was achieved. Electrolyte and acid-base balance as well as calcium homeostasis were well controlled over a period of 9 months.
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Affiliation(s)
- Beate Unver
- Division of Nephrology and Dialysis, Department of Medicine III, University of Vienna
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Agroyannis B, Fourtounas C, Tzanatos H, Dalamangas A, Vlahakos DV. Relationship between interdialytic weight gain and acid-base status in hemodialysis by bicarbonate. Artif Organs 2002; 26:385-7. [PMID: 11952511 DOI: 10.1046/j.1525-1594.2002.06883.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to determine the relationship between interdialytic weight gain and acid-base balance pre- and posthemodialysis in uremic patients undergoing hemodialysis with a high bicarbonate dialysate (39 mmol/L). To this end we studied 8 stable uremic patients on regular hemodialysis thrice weekly who had stable hematocrit values for at least 3 months, similar clinical characteristics including dry weight but widely varying interdialytic weight gain. Arterial line blood samples were collected anaerobically in heparinized syringes pre- and posthemodialysis in 4 consecutive hemodialysis sessions for the determination of pH, Paco2, and HCO3. Prehemodialysis values (mean +/- SD) were pH = 7.34 +/- 0.03, Paco2 = 36.43 +/- 1.4, and Hco3 = 20.1 +/- 1.55. Posthemodialysis values were pH= 7.47 +/- 0.02, Paco2 = 38.72 +/- 2.0, and HCO3 = 27.73 +/- 1.72. In other words, patients were moderately acidemic prior to and moderately alkalemic after the hemodialysis session. Of note, a significant negative correlation was revealed between the interdialytic weight gain and the values of prehemodialysis blood pH (r = -0.721, p < 0.001) and HCO3 (r = -0.836, p < 0.001) and posthemodialysis pH (r = -0.533, p < 0.001), Paco2 (r = -0.623, p < 0.001) and HCO3 (r = -0.815, p < 0.001), suggesting an important role of the interdialytic weight gain on acid-base equilibrium of uremic patients undergoing hemodialysis. Thus, patients with high interdialytic weight gains may require higher bicarbonate concentrations to achieve normal acid-base status whereas patients with low interdialyic weight gains may require lower bicarbonate concentrations to prevent alkalemia at the end of dialysis.
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Affiliation(s)
- B Agroyannis
- Department of Nephrology, Aretaieon University Hospital, Athens, Greece
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Abstract
In most outpatient centers the dialysate is prepared centrally such that the composition of the dialysate is the same for all patients. When delivered in this manner most patients tolerate the procedure well. However, there are patients who tolerate the procedure poorly, which has prompted a great deal of research focused on individualizing the composition of the dialysate in order to improve patient tolerability. Prescribing a patient-specific dialysate will become increasingly important as the age of and number of comorbid conditions increase in the dialysis population. Patients with end-stage renal disease (ESRD) depend on dialysis to maintain fluid and electrolyte balance. Hemodialysis allows for solutes to diffuse between blood and dialysate such that, over the course of the procedure, plasma composition is restored toward normal values. The makeup of the dialysate is of paramount importance in accomplishing this goal. In most out-patient settings patients receive hemodialysis using dialysate prepared in bulk and delivered via a central delivery system so that the composition of the dialysate is the same for all patients. While most patients tolerate the procedure when administered in this fashion, many patients suffer from hemodynamic instability or symptoms of dialysis disequilibrium. One strategy to improve the clinical tolerance to dialysis is to adjust the dialysate composition according to the individual characteristics of the patient. This article reviews recent developments on how the dialysate can be manipulated in order to improve patient tolerance. Individualizing the dialysate composition is likely to gain increasing importance given the advancing age and increasing number of comorbid conditions found in ESRD patients.
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Affiliation(s)
- B F Palmer
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas 75235, USA.
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Abstract
Bone disease in patients with chronic renal failure (CRF) is thought to be the consequence primarily of the interplay of several factors, including the serum levels of parathyroid hormone (PTH), vitamin D, calcium, and phosphorus, and exposure to bone toxins such as aluminum or amyloid. Recently the metabolic acidosis noted with CRF has been implicated as an additional factor contributing to the genesis of bone disease. Although metabolic acidosis might be the dominant factor in the cause of bone disease in some instances, more commonly this acid-base disturbance interacts with other factors contributing to the development of bone disease. The following article summarizes the data in support of an important role for metabolic acidosis in the genesis of bone disease in patients with CRF and presents our recommendations for treatment of uremic acidosis to prevent or treat the bone disease.
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Affiliation(s)
- J A Kraut
- Division of Nephrology, VA Greater Los Angeles Health Care System, Los Angeles, CA 90073, USA
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Abstract
Acid-base balance in dialysis patients is achieved by a unique interaction between the patient and the particular mode of renal replacement therapy. The prevailing serum HCO3- in these patients is determined not only by endogenous acid production but also by the nature of the dialysis prescription and, in particular, by the bicarbonate (or lactate) concentration of the bath solution. Despite the technical advances in dialysis therapy, pre-dialysis serum HCO3- remains lower than normal in most patients receiving hemodialysis and in many patients receiving peritoneal dialysis. A central question is whether even a mild degree of acidosis increases morbidity and mortality in patients with end-stage renal disease. This article reviews the nature of the acid-base equilibrium achieved in patients receiving hemodialysis or peritoneal dialysis, addresses the question of whether correction of acidosis is beneficial, and reviews the techniques for increasing serum HCO3- in these patients. Based on the information available, it is clear that the patient with a serum HCO3- less than 19 mEq/L should be assessed to determine the cause of the low value and steps undertaken to correct the acidosis. Whether patients with steady-state values between 19 and 24 mEq/L require specific attention remains an issue for further investigation.
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Affiliation(s)
- F J Gennari
- Department of Medicine, University of Vermont College of Medicine, Burlington, USA.
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Sepandj F, Jindal K, Kiberd B, Hirsch D. Metabolic acidosis in hemodialysis patients: a study of prevalence and factors affecting intradialytic bicarbonate gain. Artif Organs 1996; 20:976-80. [PMID: 8864017 DOI: 10.1111/j.1525-1594.1996.tb04583.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The correction of uremic acidosis is one of the goals of hemodialysis; however, despite acceptable hemodialysis protocols, metabolic acidosis remains a common problem. The prevalence of acidosis and significance of factors affecting bicarbonate flux during hemodialysis were studied. A cohort of 70 stable patients receiving high-efficiency hemodialysis for at least 4 months was studied prospectively over a 1-year period. Twenty patients (28%) had a mean predialysis serum bicarbonate of less than 21 mEq/L. The patients with or without metabolic acidosis had similar mean net ultrafiltration and percent ultrafiltration, but acidotic patients had a higher percent increase in bicarbonate during hemodialysis (35 +/- 12 versus 27 +/- 10 [p = 0.008]). The latter suggests an increased net daily acid gain in patients with metabolic acidosis (1.19 +/- 0.32 mEq/kg versus 1.05 +/- 0.35 mEq/kg [p = 0.04]). A review of factors affecting intradialytic bicarbonate gain showed that predialysis serum bicarbonate (diffusive gradient) was the most significant with a demonstrated linear relationship between these two variables (R2 0.51). The role of dialysance and blood flow, assessed together using percent urea reduction, was minor as was the effect of ultrafiltration. At our level of dialysis delivery, prevalence of metabolic acidosis is low, and dialysis-related factors do not contribute to the persistence of metabolic acidosis. Net daily acid gain was higher in acidotic patients and accounts for the long-term maintenance of metabolic acidosis. For individual dialysis treatments, the diffusive gradient is the most important determinant of bicarbonate gain, with only a minor role being demonstrated for percent urea reduction and ultrafiltration rate.
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Affiliation(s)
- F Sepandj
- Dalhousie University, Halifax, Nova Scotia, Canada
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