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Valga F, Monzón T, Vega-Diaz N, Rodriguez-Perez JC, Ruiz-Santana S. Inflammation and hemodialysis adequacy: are C-reactive protein levels influenced by the dose of dialysis? Nefrologia 2022; 42:163-170. [PMID: 36153912 DOI: 10.1016/j.nefroe.2021.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 06/06/2021] [Indexed: 06/16/2023] Open
Abstract
INTRODUCTION Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the "dialysis dose" with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the "dialysis dose" (Kt / V) using ionic dialysance. METHODS Multicenter cross-sectional study. 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into two groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence. RESULTS Median CRP was 4.10 mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48 ± 0.308. Kt/V was lower in the patients included in the high inflammation group (p = 0.01). In the multivariate logistic regression, the "high" levels of CRP were directly correlated with the Log INL (p < 0.001) and inversely proportional with serum albumin values (p = 0.014), Kt/V (p = 0.037) and serum iron (p < 0.001). CONCLUSION The poorer adequacy in terms of dialysis doses, lower Kt / V values, may contribute to a higher degree of inflammation in chronic hemodialysis patients.
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Affiliation(s)
- Francisco Valga
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, Spain; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, Spain.
| | - Tania Monzón
- Centro de Hemodiálisis Avericum Negrín, Las Palmas de Gram Canaria, Spain.
| | - Nicanor Vega-Diaz
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, Spain; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, Spain.
| | - José Carlos Rodriguez-Perez
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, Spain; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, Spain.
| | - Sergio Ruiz-Santana
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, Spain; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, Spain
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Guía de unidades de hemodiálisis 2020. Nefrologia 2021. [DOI: 10.1016/j.nefro.2021.07.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Valga F, Monzón T, Vega-Diaz N, Rodriguez-Perez JC, Ruiz-Santana S. Inflammation and hemodialysis adequacy: Are C-reactive protein levels influenced by dialysis dose? Nefrologia 2021; 42:S0211-6995(21)00112-0. [PMID: 34238598 DOI: 10.1016/j.nefro.2021.06.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 05/06/2021] [Accepted: 06/06/2021] [Indexed: 10/20/2022] Open
Abstract
INTRODUCTION Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the "dialysis dose" (Kt/V) with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the Kt/V using ionic dialysance. METHODS Multicenter cross-sectional study. A total of 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into 2 groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence. RESULTS Median CRP was 4.10mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48±0.308. Kt/V was lower in the patients included in the high inflammation group (P=.01). In the multivariate logistic regression, the "high" levels of CRP were directly correlated with the Log neutrophil-lymphocyte ratio (P<.001) and inversely proportional with serum albumin values (P=.014), Kt/V (P=.037) and serum iron (P<.001). CONCLUSION The poorer adequacy in terms of dialysis doses (lower Kt/V values) may contribute to a higher degree of inflammation in chronic hemodialysis patients.
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Affiliation(s)
- Francisco Valga
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, España; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, España.
| | - Tania Monzón
- Centro de Hemodiálisis Avericum Negrín, Las Palmas de Gran Canaria, España
| | - Nicanor Vega-Diaz
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, España; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, España
| | - José Carlos Rodriguez-Perez
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, España; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, España
| | - Sergio Ruiz-Santana
- Servicio de Nefrología, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Las Palmas, España; Programa de Doctorado en Investigación en Biomedicina, Facultad de Ciencias de la Salud, Departamento de Ciencias Clínicas, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Las Palmas, España
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Béguin L, Krummel T, Longlune N, Galland R, Couchoud C, Hannedouche T. Dialysis dose and mortality in hemodialysis: Is higher better? Nephrol Dial Transplant 2021; 36:2300-2307. [PMID: 34145896 DOI: 10.1093/ndt/gfab202] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The effect of dialysis dose on mortality remains unsettled. Current guidelines recommend to target a spKt/V at 1.20 to 1.40 per tri-weekly dialysis session. However, the optimal dialysis dose remains mostly disputed. METHODS In a nationwide registry of all incident patients receiving thrice-weekly hemodialysis, 32 283 patients had available data on dialysis dose, estimated by Kt/V and its variants Kt and Kt/A. Survival was analyzed with a multivariate Cox model and a concurrent risk model accounting for renal transplantation. A predictive model of Kt in the upper quartile was developed. RESULTS Regardless of the indicator, a higher dose of dialysis was consistently associated with better survival. The survival differential of Kt was the most discriminating, but marginally, compared to the survival differential according to Kt/V and Kt/A. Patient survival was higher in the upper quartile of Kt (> 69L/s), then deteriorated as the Kt decreased with a difference in survival between the upper and lower quartile of 23.6% at five years. Survival differences across Kt distribution were similar after accounting for kidney transplantation as a competing risk. Predictive factors for Kt in the upper quartile were arteriovenous fistula versus catheters and graft, hemodiafiltration versus hemodialysis, scheduled dialysis start versus emergency start, long weekly dialysis duration, spKt/V measurement versus double pool eKt/V. CONCLUSION Our data confirm the existence of a relationship between dialysis dose and survival, which persisted despite correcting for known confounders. A model for predicting a high dose of dialysis is proposed with practical relevance.
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Affiliation(s)
- Lisa Béguin
- Department of Nephrology, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Thierry Krummel
- Department of Nephrology, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | | | | | - Cécile Couchoud
- Registre REIN, Agence de Biomédecine, Saint Denis La Plaine Cedex, France
| | - Thierry Hannedouche
- Department of Nephrology, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.,School of Medicine, University of Strasbourg, Strasbourg, France
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Petitclerc T, Ridel C. Routine online assessment of dialysis dose: Ionic dialysance or UV-absorbance monitoring? Semin Dial 2021; 34:116-122. [PMID: 33529406 DOI: 10.1111/sdi.12949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 11/01/2020] [Accepted: 12/17/2020] [Indexed: 11/29/2022]
Abstract
For three-weekly hemodialysis, a single-pool Kt/V target of at least 1.4 together with a minimal dialysis dose Kt at 45 L for men and 40 L for women per each session is currently recommended. Fully automatic online calculation of Kt and Kt/V from conductivity or UV-absorbance measurements in the dialysate is standardly implemented on some hemodialysis monitors and makes it possible to estimate the dialysis dose without the need for blood or dialysate samples. Monitoring the UV-absorbance of the spent dialysate is the most direct method for estimating Kt/V as it does not require an estimate of V. Calculation of ionic dialysance from conductivity measurements is the most direct method for estimating Kt and BSA-scaled dialysis dose. Both ionic dialysance monitoring and UV-absorbance monitoring may help detect a change in urea clearance occurring during the session, but this change must be interpreted differently depending on the monitoring being considered. An abrupt decrease in urea clearance results in a decrease in ionic dialysance but, paradoxically, a sudden increase in estimated urea clearance provided by dialysate UV-absorbance monitoring. Healthcare teams who monitor both ionic dialysance and UV-absorbance in their hemodialysis units must be clearly informed of this difficulty.
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Colussi G, Brunati CCM, Gervasi F, Montoli A, Vergani D, Curci F, Minetti E. A simple method for the calculation of dialysis Kt factor as a quantitative measure of removal efficiency of uremic retention solutes: Applicability to high-dialysate vs low-dialysate volume technologies. PLoS One 2020; 15:e0233331. [PMID: 32469929 PMCID: PMC7259768 DOI: 10.1371/journal.pone.0233331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 05/02/2020] [Indexed: 12/03/2022] Open
Abstract
Dialysis urea removal metrics may not translate into proportional removal efficiency of non-urea solutes. We show that the Kt factor (plasma volume totally cleared of any solutes) differentiates removal efficiency of non-urea solutes in different technologies, and can easily be calculated by instant blood-dialysate collections. We performed mass balances of urea, creatinine, phosphorus and beta2-microglobulin by whole dialysate collection in 4 low-flux and 3 high-flux hemodialysis, 2 high-volume post-hemodiafiltration and 7 short-daily dialysis with the NxStage-One system. Instant dialysate/blood determinations were also performed at different times, and Kt was calculated as the product of the D/P ratio by volume of delivered dialysate plus UF. There were significant differences in single session and weekly Kt (whole dialysate and instant calculations) between methodologies, most notably for creatinine, phosphorus and beta2-microglobulin. Urea Kt messured in balance studies was almost equal to that derived from the usual plasma kinetic model-based Daugirdas’ equation (eKt/V) and independent V calculation, indicating full correspondence. Non-urea solute Kt as a fraction of urea Kt (i.e. fractional removal relative to urea) showed significant differences between technologies, indicating non-proportional removal of non-urea solutes and urea. Instant Kt was higher than that in full balances, accounting for concentration disequilibrium between arterial and systemic blood, but measured and calculated quantitative solute removal were equal, as were qualitative Kt comparisons between technologies. Thus, we show that urea metrics may not reliably express removal efficiency of non-urea solutes, as indicated by Kt. Kt can easily be measured without whole dialysate collection, allowing to expand the metrics of dialytic efficiency to almost any non-urea solute removed by dialysis.
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Affiliation(s)
- Giacomo Colussi
- Division of Nephrology, Dialysis and Renal Transplantation, ASST GOM Niguarda, Milan, Italy
- Ambrosiana Clinic-Sacra Famiglia Foundation, Milan, Italy
- * E-mail: ,
| | | | - Francesca Gervasi
- Division of Nephrology, Dialysis and Renal Transplantation, ASST GOM Niguarda, Milan, Italy
- Nephrology School, Milano-Bicocca University, Milan, Italy
| | - Alberto Montoli
- Division of Nephrology, Dialysis and Renal Transplantation, ASST GOM Niguarda, Milan, Italy
| | - Denise Vergani
- Division of Nephrology, Dialysis and Renal Transplantation, ASST GOM Niguarda, Milan, Italy
| | - Federica Curci
- Division of Nephrology, Dialysis and Renal Transplantation, ASST GOM Niguarda, Milan, Italy
| | - Enrico Minetti
- Division of Nephrology, Dialysis and Renal Transplantation, ASST GOM Niguarda, Milan, Italy
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Abstract
Dialyzer clearance of urea multiplied by dialysis time and normalized for urea distribution volume (Kt/Vurea or simply Kt/V) has been used as an index of dialysis adequacy since more than 30 years. This article reviews the flaws of Kt/V, starting with a lack of proof of concept in three randomized controlled hard outcome trials (RCTs), and continuing with a long list of conditions where the concept of Kt/V was shown to be flawed. This information leaves little room for any conclusion other than that Kt/V, as an indicator of dialysis adequacy, is obsolete. The dialysis patient might benefit more if, instead, the nephrology community concentrates in the future on pursuing the optimal dialysis dose that conforms with adequate quality of life and on factors that are likely to affect outcomes more than Kt/V. These include residual renal function, volume status, dialysis length, ultrafiltration rate, the number of intra-dialytic hypotensive episodes, interdialytic blood pressure, serum potassium and phosphate, serum albumin, and C reactive protein.
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Affiliation(s)
- Raymond Vanholder
- Nephrology Section, Department of Internal Medicine, University Hospital Ghent, Ghent, Belgium
| | - Wim Van Biesen
- Nephrology Section, Department of Internal Medicine, University Hospital Ghent, Ghent, Belgium
| | - Norbert Lameire
- Nephrology Section, Department of Internal Medicine, University Hospital Ghent, Ghent, Belgium
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Farrington K, Davenport A. Would prescribing target Kt dose adjusted for body surface area improve hemodialysis outcomes? Kidney Int 2019; 90:1160-1162. [PMID: 27884309 DOI: 10.1016/j.kint.2016.09.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 09/19/2016] [Indexed: 10/20/2022]
Abstract
The use of Kt/V to prescribe and monitor hemodialysis adequacy remains the current standard, although it is increasingly questioned. Alternative proposals for dose prescription and monitoring have been advocated. In a noninterventional, prospective study reported in this issue, Maduell et al., utilizing online ionic dialysance, explore the association between outcome measures (mortality and hospitalization rates) and the extent to which delivered Kt dose achieved minimal target Kt doses calculated from individual estimates of body surface area.
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Affiliation(s)
- Ken Farrington
- Renal Unit, Lister Hospital, Stevenage, United Kingdom; University of Hertfordshire, Hatfield, UK
| | - Andrew Davenport
- UCL Centre for Nephrology, Royal Free Hospital, University College London, London, UK.
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Leypoldt JK, Weinhandl ED, Collins AJ. Volume of urea cleared as a therapy dosing guide for more frequent hemodialysis. Hemodial Int 2018; 23:42-49. [PMID: 30255600 DOI: 10.1111/hdi.12692] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/05/2018] [Indexed: 01/29/2023]
Abstract
INTRODUCTION With dialysis delivery systems that operate at low dialysate flow rates, prescriptions for more frequent hemodialysis (HD) employ dialysate volume as the primary parameter for small solute removal rather than blood-side urea dialyzer clearance (K). Such delivery systems, however, yield dialysate concentrations that almost completely saturate with blood (water), suggesting that the volume of urea cleared (the product of K and treatment time or Kt) can be readily estimated from the prescribed dialysate volume to target small solute removal. Methods For more frequent HD, we examined the volume of urea cleared per treatment required to achieve a minimal dose of small solute removal, comparing results based on body surface area (BSA) with those based on KDOQI clinical practice guidelines, that is, a weekly stdKt/V of 2.1. Estimates of the target volume of urea cleared were calculated for 4, 5, and 6 treatments per week, and compared for patients with different anthropometric estimates of total body water volume (Vant ). BSA was assumed proportional to Vant 0.8 , and residual kidney function was neglected. Findings Whether based on BSA or weekly stdKt/V of 2.1, the target volume of urea cleared per treatment required to achieve a minimal dose of small solute removal was lower at higher treatment frequency. As with conventional thrice-weekly HD, target volumes of urea cleared for more frequent HD based on BSA were larger for patients with small Vant and smaller for patients with large Vant than those based on a weekly stdKt/V of 2.1. Discussion Prescription of more frequent HD using the volume of urea cleared per treatment, calculated from the prescribed dialysate volume, is simple in principle and can be readily implemented in clinical practice when using dialysis delivery systems that operate at low dialysate flow rates. Other aspects of dialysis adequacy require additional consideration.
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Affiliation(s)
| | - Eric D Weinhandl
- NxStage Medical, Lawrence, Massachusetts, USA.,Department of Pharmaceutical Care and Health Systems, University of Minnesota, Minneapolis, Minnesota, USA
| | - Allan J Collins
- NxStage Medical, Lawrence, Massachusetts, USA.,Medical School, University of Minnesota, Minneapolis, Minnesota, USA
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Pérez-García R, Jaldo M, Alcázar R, de Sequera P, Albalate M, Puerta M, Ortega M, Ruiz MC, Corchete E. Unlike Kt, high Kt/V is associated with greater mortality: The importance of low V. Nefrologia 2018; 39:58-66. [PMID: 30075965 DOI: 10.1016/j.nefro.2018.04.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 02/26/2018] [Accepted: 04/03/2018] [Indexed: 10/28/2022] Open
Abstract
INTRODUCTION Kt/V has been used as a synonym for haemodialysis dose. Patient survival improved with a Kt/V>1; this target was subsequently increased to 1.2 and 1.3. The HEMO study revealed no significant relationship between Kt/V and mortality. The relationship between Kt/V and mortality often shows a J-shaped curve. Is V the confounding factor in this relationship? The objective of this study is to determine the relationship between mortality and Kt/V, Kt and body water content (V) and lean mass (bioimpedance). METHODS We studied a cohort of 127 prevalent haemodialysis patients, who we followed-up for an average of 36 months. Kt was determined by ionic dialysance, and V and nutrition parameters by bioimpedance. Kt/V, Kt corrected for body surface area (Kt/BSA) and target Kt/BSA were calculated. The mean data from 18,998 sessions were used as haemodialysis parameters, with a mean of 155 sessions per patient. RESULTS Mean age was 70.4±15.3 years and 61% were male; 76 were dialysed via an arteriovenous fistula and 65 were on online haemodiafiltration. Weight was 70.6 (16.8)kg; BSA 1.8 (0.25) m2; total body water (V) 32.2 (7.41) l and lean mass index (LMI) 11.1 (2.7)kg/m2. Mean Kt/V was 1.84 (0.44); Kt 56.1 (7)l and Kt/BSA 52.8 (10.4)l. The mean target Kt/BSA was 49.7 (4.5)l. Mean Kt/BSA-target Kt/BSA +6.4 (7.0)l. Patients with a higher Kt/V had worse survival rates than others; with Kt this is not the case. Higher Kt/V values are due to a lower V, with poorer nutrition parameters. LMI and serum albumin were the parameters that best independently predicted the risk of death and are lower in patients with a higher Kt/V and lower V. CONCLUSION Kt/V is not useful for determining dialysis doses in patients with low or reduced body water. Kt or the Kt/BSA are proposed as an alternative.
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Affiliation(s)
- Rafael Pérez-García
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España.
| | - Maite Jaldo
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - Roberto Alcázar
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - Patricia de Sequera
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - Marta Albalate
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - Marta Puerta
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - Mayra Ortega
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - M Caridad Ruiz
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
| | - Elena Corchete
- Servicio de Nefrología, Hospital Universitario Infanta Leonor, Madrid, España
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Abstract
BACKGROUND Kt/Vurea reflects the efficacy of haemodialysis scaled to patient size (urea distribution volume). The guidelines recommend monthly Kt/V measurements based on blood samples. Modern haemodialysis machines are equipped with accessories monitoring the dose online at every session without extra costs, blood samples and computers. OBJECTIVE To describe the principles, devices, benefits and shortcomings of online monitoring of haemodialysis dose. DESIGN A critical literature overview and discussion. RESULTS UV absorbance methods measure Kt/V, ionic dialysance Kt (product of clearance and treatment time; cleared volume without scaling). Both are easy and useful methods, but comparison is difficult due to problems in scaling of the dialysis dose to the patient's size. CONCLUSIONS The best dose estimation method is the one which predicts the quality of life and survival most accurately. There is some evidence on the predictive value of ionic dialysance Kt, but more documentation is required on the UV method. Online monitoring is a useful tool in everyday quality assurance, but blood samples are still required for more accurate kinetic modelling. LEARNING OUTCOMES After reading this article the reader should be able to: Understand the elements of the Kt/V equation for dialysis dose. Compare and contrast different methods of measurement of dialysis dose. Reflect on the importance of adequate dialysis dose for patient survival and life quality.
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Affiliation(s)
- Aarne Vartia
- Retired from Savonlinna Central Hospital, Savonlinna, Finland
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12
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Hemodialysis patients receiving a greater Kt dose than recommended have reduced mortality and hospitalization risk. Kidney Int 2016; 90:1332-1341. [DOI: 10.1016/j.kint.2016.08.022] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 08/05/2016] [Accepted: 08/18/2016] [Indexed: 01/02/2023]
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Molina Nuñez M, de Alarcón R, Roca S, Álvarez G, Ros MS, Jimeno C, Bucalo L, Villegas I, García MÁ. Citrate versus acetate-based dialysate in on-line haemodiafiltration. A prospective cross-over study. Blood Purif 2016; 39:181-187. [PMID: 25791278 DOI: 10.1159/000371569] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/14/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND AND AIMS A bicarbonate dialysate acidified with citrate (CD) has been reported to have local anticoagulant effect and improves biocompatibility. This study examines the effect of CD on dialysis efficiency, coagulation, acid-base status, electrolytes, and inflammation in patients in on-line hemodiafiltration (OL-HDF). METHODS 35 patients in OL-HDF were enrolled in a prospective, cross-over study for a 24-week period and two phases alternating CD and acetate dialysate fluid (AD). Parameters on study were predialysis levels of bicarbonate and ionic calcium, reactive C Protein (CRP), and beta-2 microglobulin (B2MG) and postdialysis levels of activated tromboplastine time, bicarbonate, and ionized calcium. RESULTS No significant differences in coagulation parameters, pH, and predialysis bicarbonate were found. The postdialysis bicarbonate and postdialysis calcium were lower with CD. Dialysis efficiency was greater with CD. Regarding inflammatory parameters, both CRP and B2MG were lower using CD. CONCLUSION The use of CD is safe and effective in OL-HDF, and it improves dialysis efficacy, postdialysis alkalosis, and inflammation.
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Albalate Ramón M, de Sequera Ortiz P, Pérez-García R, Corchete Prats E, Alcázar Arroyo R, Ortega Díaz M, Puerta Carretero M. What is the optimum dialysate flow in post-dilution online haemodiafiltration? Nefrologia 2015; 35:533-8. [PMID: 26565938 DOI: 10.1016/j.nefro.2015.04.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 04/13/2015] [Indexed: 11/16/2022] Open
Abstract
INTRODUCTION In post-dilution online hemodiafiltration (OL-HDF), the only recommendation concerning the dialysate, or dialysis fluid, refers to its purity. No study has yet determined whether using a high dialysate flow (Qd) is useful for increasing Kt or ultrafiltration-infusion volume. OBJECTIVE Study the influence of Qd on Kt and on infusion volume in OL-HDF. MATERIAL AND METHODS This was a prospective crossover study. There were 37 patients to whom 6 sessions of OL-HDF were administered at 3 different Qds: 500, 600 and 700ml/min. A 5008(®) monitor was used for the dialysis in 21 patients, while an AK-200(®) was used in 17. The dialysers used were: 20 with FX 800(®) and 17 with Polyflux-210(®). The rest of the parameters were kept constant. Monitor data collected were effective blood flow, effective dialysis time, final Kt and infused volume. RESULTS We found that using a Qd of 600 or 700ml/min increased Kt by 1.7% compared to using a Qd of 500ml/min. Differences in infusion volume were not significant. Increasing Qd from 500ml/min to 600 and 700ml/min increased dialysate consumption by 20% and 40%, respectively. CONCLUSIONS With the monitors and dialysers currently used in OL-HDF, a Qd higher than 500ml/min is unhelpful for increasing the efficacy of Kt or infusion volume. Consequently, using a high Qd wastes water, a truly important resource both from the ecological and economic points of view.
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Albalate M, Pérez-García R, de Sequera P, Corchete E, Alcazar R, Ortega M, Puerta M. Is it useful to increase dialysate flow rate to improve the delivered Kt? BMC Nephrol 2015; 16:20. [PMID: 25884763 PMCID: PMC4369100 DOI: 10.1186/s12882-015-0013-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 02/04/2015] [Indexed: 11/29/2022] Open
Abstract
Background Increasing dialysate flow rates (Qd) from 500 to 800 ml/min has been recommended to increase dialysis efficiency. A few publications show that increasing Qd no longer led to an increase in mass transfer area coefficient (KoA) or Kt/V measurement. Our objectives were: 1) Studying the effect in Kt of using a Qd of 400, 500, 700 ml/min and autoflow (AF) with different modern dialysers. 2) Comparing the effect on Kt of water consumption vs. dialysis time to obtain an individual objective of Kt (Ktobj) adjusted to body surface. Methods This is a prospective single-centre study with crossover design. Thirty-one patients were studied and six sessions with each Qd were performed. HD parameters were acquired directly from the monitor display: effective blood flow rate (Qbe), Qd, effective dialysis time (Te) and measured by conductivity monitoring, final Kt. Results We studied a total of 637 sessions: 178 with 500 ml/min, 173 with 700 ml/min, 160 with AF and 126 with 400 ml/min. Kt rose a 4% comparing 400 with 500 ml/min, and 3% comparing 500 with 700 ml/min. Ktobj was reached in 82.4, 88.2, 88.2 and 94.1% of patients with 400, AF, 500 and 700 ml/min, respectively. We did not find statistical differences between dialysers. The difference between programmed time and Te was 8′ when Qd was 400 and 500 ml/min and 8.8′ with Qd = 700 ml/min. Calculating an average time loss of eight minutes/session, we can say that a patient loses 24′ weekly, 312′ monthly and 62.4 hours yearly. Identical Kt could be obtained with Qd of 400 and 500 ml/min, increasing dialysis time 9.1′ and saving 20% of dialysate. Conclusions Our data suggest that increasing Qd over 400 ml/min for these dialysers offers a limited benefit. Increasing time is a better alternative with demonstrated benefits to the patient and also less water consumption. Electronic supplementary material The online version of this article (doi:10.1186/s12882-015-0013-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marta Albalate
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
| | - Rafael Pérez-García
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
| | - Patricia de Sequera
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
| | - Elena Corchete
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
| | - Roberto Alcazar
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
| | - Mayra Ortega
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
| | - Marta Puerta
- Servicio de Nefrologia, Hospital Universitario Infanta Leonor, Gran Vía del Este, No 80, 28031, Madrid, Spain.
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Maduell F, Ramos R, Palomares I, Martin-Malo A, Molina M, Bustamante J, Perez-Garcia R, Grassmann A, Merello JI. Impact of targeting Kt instead of Kt/V. Nephrol Dial Transplant 2013; 28:2595-603. [DOI: 10.1093/ndt/gft255] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Grangé S, Hanoy M, Le Roy F, Guerrot D, Godin M. Monitoring of hemodialysis quality-of-care indicators: why is it important? BMC Nephrol 2013; 14:109. [PMID: 23705852 PMCID: PMC3701507 DOI: 10.1186/1471-2369-14-109] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 05/03/2013] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Meeting specific guideline targets is associated with improved survival rates and reduced hospitalizations in the dialysis population. This prospective work evaluated the adequacy of hemodialysis quality indicators in an in-center hemodialysis population with severe comorbidities, and assessed whether clinical practice could impact intermediate outcomes. METHODS All the chronic hemodialysis patients treated in Rouen University Hospital hemodialysis Unit between January 2009 and April 2010 were included in this observational study. Every quarter, mean levels and prevalence of conformity were collected for the following indicators: anemia, dialysis dose, serum calcium and phosphorus, PTH, 25OH-vitamin D, albumin, serum bicarbonate, LDL-cholesterol, serum β2-microglobulin, systolic and diastolic blood pressure, intradialytic hypotension and vascular access. Conformity of quality-of-care indicators was determined according to targets defined by international guidelines, whenever available. RESULTS Altogether, 124 patients were included in the study. Thirty-three patients were evaluated during the entire follow-up period. An improvement in the percentage of conformity was observed for hemoglobin, dialysis dose, phosphates, PTH, serum bicarbonate and β2-microglobulin in the global population. Failure to improve conformity rates for several indicators, including serum albumin, was found, possibly depending on patients' comorbidities rather than on quality of care. CONCLUSION Overall, this study shows that following quality-of-care indicators can improve clinical practice by identifying center-specific weaknesses, prompting the establishment of corrective measures. Finally, we suggest that the definition and targets of some indicators, especially hypertension and LDL-cholesterol, be reviewed, since evidence of their association with mortality is not demonstrated.
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Affiliation(s)
- Steven Grangé
- Nephrology department, Rouen University Hospital, 1 Avenue de Germont 76031 Rouen Cedex, Rouen, France
| | - Mélanie Hanoy
- Nephrology department, Rouen University Hospital, 1 Avenue de Germont 76031 Rouen Cedex, Rouen, France
| | - Frank Le Roy
- Nephrology department, Rouen University Hospital, 1 Avenue de Germont 76031 Rouen Cedex, Rouen, France
| | - Dominique Guerrot
- Nephrology department, Rouen University Hospital, 1 Avenue de Germont 76031 Rouen Cedex, Rouen, France
- INSERM Unit 1096, Rouen University Medical School, Rouen, France
| | - Michel Godin
- Nephrology department, Rouen University Hospital, 1 Avenue de Germont 76031 Rouen Cedex, Rouen, France
- INSERM Unit 1096, Rouen University Medical School, Rouen, France
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Szamosfalvi B, Yee J. Considerations in the critically ill ESRD patient. Adv Chronic Kidney Dis 2013; 20:102-9. [PMID: 23265602 DOI: 10.1053/j.ackd.2012.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 10/25/2012] [Accepted: 10/25/2012] [Indexed: 12/21/2022]
Abstract
ESRD patients are admitted more frequently to intensive care units (ICUs) and have higher mortality risks than the general population, and the main causes of critical illness among ESRD patients are cardiovascular events, sepsis, and bleeding. Once in the ICU, hemodynamic stabilization and fluid-electrolyte management pose major challenges in oligoanuric patients. Selection of renal replacement therapy (RRT) modality is influenced by the outpatient modality and access, as well as severity of illness, renal provider experience, and ICU logistics. Currently, most patients receive intermittent hemodialysis or continuous RRT with temporary vascular access catheters. Acute peritoneal dialysis (PD) is less frequently utilized, and utility of outpatient PD is reduced after an ICU admission. Thus, preservation of current vascular accesses, while limiting venous system damage for future access creations, is relevant. Also, dosing of small-solute clearance with urea kinetic modeling is difficult and may be supplanted by novel online clearance techniques. Medication dosing, coordinated with delivered RRT, is essential for septic patients treated with antibiotics. A comprehensive, standardized approach by a multidisciplinary team of providers, including critical care specialists, nephrologists, and pharmacists, represents a nexus of care that can reduce readmission rates, morbidity, and mortality of vulnerable ESRD patients.
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Fissell R, Schulman G, Pfister M, Zhang L, Hung AM. Novel dialysis modalities: do we need new metrics to optimize treatment? J Clin Pharmacol 2012; 52:72S-8S. [PMID: 22232756 DOI: 10.1177/0091270011414576] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Delivered dose of hemodialysis has long been an important predictor of mortality. The limitations of conventional hemodialysis treatments have led to a renewed interest in more frequent and longer hemodialysis treatments. As alternative hemodialysis schedules have become more prevalent, a need for modified metrics to measure adequacy has emerged. In addition, there is an interest in finding measures of hemodialysis adequacy that are more reliable in certain subgroups of patients, such as women, ethnic minority groups, or people with small body size. Finally, extended hemodialysis schedules suggest a need for metrics that can measure the clearance of solutes other than urea, such as middle-size molecules, and solutes for which clearance depends on intercompartmental transport across membranes. New metrics to quantify clearance in extended and alternate hemodialysis schedules are needed. As new metrics are developed, it is anticipated that they will also contribute to more accurate assessments of associations between clinical outcomes and delivered dose of dialysis in more intensive, nontraditional hemodialysis schedules. This review provides a historical prospective of dialysis dose and adequacy and describes the need for new metrics from both solute type and dialysis dose prospective as alternative hemodialysis schedules have emerged and become more prevalent.
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Affiliation(s)
- Rachel Fissell
- Glickman Urological/Kidney Institute, Cleveland Clinic, Cleveland, Ohio, USA
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Chan KE, Pflederer TA, Steele DJR, Lilly MP, Ikizler TA, Maddux FW, Hakim RM. Access survival amongst hemodialysis patients referred for preventive angiography and percutaneous transluminal angioplasty. Clin J Am Soc Nephrol 2011; 6:2669-80. [PMID: 21959600 DOI: 10.2215/cjn.02860311] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Referring hemodialysis patients for elective access angiography and percutaneous transluminal angioplasty (PTA) is commonly done to prevent access failure, yet the effectiveness of this procedure remains unclear. DESIGN, SETTING, PARTICIPANTS, & MEASURES: An observational matched cohort analysis among 40,132 Medicare beneficiaries receiving hemodialysis with a fistula or graft was performed. Cox regression was used to determine whether access intervention was associated with improved 1-year access survival. RESULTS Nonsurgical access intervention was found to be frequent at a rate of 20.9 procedures per 100 access years. In the 1-year period after intervention using angiography and PTA, the overall access failure rate was 53.7 per 100 access years in the intervention group and 49.6 in the nonintervention group (HR = 1.02; 95% CI, 0.96 to 1.08). Similar findings were also seen when the analysis was repeated in only fistulas (HR = 1.06; 95% CI, 0.98 to 1.15) and grafts (HR = 0.95; 95% CI, 0.86 to 1.05). In patients with a low intra-access flow rate (HR = 0.86; 95% CI, 0.75 to 0.99) or a new access (HR = 0.79; 95% CI, 0.71 to 0.89), angiography and PTA significantly increased access survival when compared with nonintervention (P for interaction was <0.0001). Angiography-PTA-related upper-extremity hematoma, vessel injury, or embolism-thrombosis occurred in 1.1% of all patients. CONCLUSIONS Access characteristics significantly modify the survival benefits of angiography and PTA intervention where the benefits of these interventions are most seen in newer accesses or accesses with insufficient flow.
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Affiliation(s)
- Kevin E Chan
- Clinical Research Division, Fresenius Medical Care North America, Waltham, MA 02451, USA.
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Lowrie EG. Illustrating Use of a Clinical Data System: The NMC-FMC System. Clin J Am Soc Nephrol 2009; 4 Suppl 1:S41-8. [DOI: 10.2215/cjn.02680409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Lacson E, Wang W, Hakim RM, Teng M, Lazarus JM. Associates of mortality and hospitalization in hemodialysis: potentially actionable laboratory variables and vascular access. Am J Kidney Dis 2008; 53:79-90. [PMID: 18930570 DOI: 10.1053/j.ajkd.2008.07.031] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Accepted: 07/29/2008] [Indexed: 01/07/2023]
Abstract
BACKGROUND To determine the most significant potentially actionable clinical variables associated with mortality and hospitalization risk in hemodialysis (HD) patients. STUDY DESIGN Cohort study. SETTING & PARTICIPANTS Adult maintenance HD patients in the Fresenius Medical Care, North America database as of January 1, 2004, with baseline information from October 1, 2003, to December 31, 2003, comprising approximately 26% of the US HD population. PREDICTORS Case-mix (age, sex, race, diabetes, vintage, and body surface area), vascular access, and laboratory (albumin, equilibrated Kt/V, hemoglobin, calcium, phosphorus, creatinine, bicarbonate, biointact parathyroid hormone, transferrin saturation, and white blood cell count) variables. OUTCOMES 1-year mortality and hospitalization risk from January 1 to December 31, 2004. MEASUREMENTS Cox proportional hazards models for death and hospitalization. RESULTS The cohort (N = 78,420) had a mean age of 61.4 +/- 15.0 years, 47% were women, 49% were white, 41% were black race (10% defined as "other"), and 52% had diabetes. The top 5 actionable variables were the same for mortality and hospitalization. Final case-mix plus laboratory-adjusted hazard ratios for these top 5 actionable variables indicate 177% increased risk of death and 67% increased risk of hospitalization per 1-g/dL decrease in albumin level, 39% and 45% greater risk with catheters compared with fistulas, 18% and 9% greater risk per 1-mg/dL greater phosphorus level, 11% and 9% lower risk per 1-g/dL greater hemoglobin level, and 5% and 2% greater risk per 0.1-unit decrease in equilibrated Kt/V, respectively (all P < 0.0001). LIMITATIONS Observational cross-sectional study with limited comorbidity adjustment (for diabetes). CONCLUSION The same variables are associated with both mortality and hospitalization in HD patients. The top 5 potentially actionable variables are readily identifiable, with albumin level and catheter use the most prominent, and all 5 are appropriate targets for improvement.
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Affiliation(s)
- Eduardo Lacson
- Fresenius Medical Care North America, 920 Winter St., Waltham, MA 02451-1457, USA.
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Abstract
Small patients require higher Kt/V, the ratio of dialysis dose (the product of small-molecule clearance (K) and dialysis session length (t) to body water volume (V), than large patients. The errors implicit in Kt/V for judging hemodialysis dose are reviewed; methods for prescribing hemodialysis based on new technology are discussed; and thoughts about future development are suggested.
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Maduell F, Vera M, Arias M, Serra N, Blasco M, Bergadá E, Fontsere N, Cases A, Campistol JM. Influence of the Ionic Dialysance Monitor on Kt Measurement in Hemodialysis. Am J Kidney Dis 2008; 52:85-92. [DOI: 10.1053/j.ajkd.2008.03.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Accepted: 03/11/2008] [Indexed: 11/11/2022]
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Abstract
Current guidelines suggest a minimum Kt/V of 1.2 for three weekly hemodialysis sessions; however, using V as a normalizing factor has been questioned. Parameters such as weight(0.67) (W(0.67)) and body surface area (BSA) that reflect the metabolic rate may be preferable. To determine this, we studied 328 hemodialysis patients (221 male) with a target Kt/V of 1.2. Using this relationship and the individual's Watson Volume, we calculated the Kt, Kt/BSA, and Kt/W(0.67) equivalent to the target and measured the effects of body size and gender on these parameters for each patient. The target corresponded to a range of equivalent Kt/BSA and Kt/W(0.67) each significantly higher in males than females and in larger than smaller males. V/BSA and V/W(0.67), the conversion factors of Kt/V to Kt/BSA and Kt/W(0.67) respectively, were significantly greater in males than females and heavier than lighter men. Our study shows that if Kt/BSA and Kt/W(0.67) reflect the true required dose, prescribing a target Kt/V of 1.2 would underestimate this in females and in small males. Further work is required to develop clinical outcome-based adequacy targets.
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Lowrie EG. The kinetic behaviors of urea and other marker molecules during hemodialysis. Am J Kidney Dis 2007; 50:181-3. [PMID: 17660018 DOI: 10.1053/j.ajkd.2007.06.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2007] [Accepted: 06/19/2007] [Indexed: 11/11/2022]
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Morton AR, Singer MA. The problem with Kt/V: dialysis dose should be normalized to metabolic rate not volume. Semin Dial 2007; 20:12-5. [PMID: 17244112 DOI: 10.1111/j.1525-139x.2007.00232.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Current estimates of hemodialysis adequacy are based on calculations of small solute clearance or changes in online measurements of ionic conductance. A minimum target value of the widely used, dimensionless parameter, Kt/V(urea) has been adopted nationally and internationally to represent appropriate dialysis delivery. Based on the principles of allometry, which permit the calculation of scaling equations between the mass of an organism and other parameters, we propose that dialysis dose should be normalized to waste product generation (estimated by metabolic rate). The allometric equations predict a nonlinear correlation between body mass and dialysis dose, such that smaller individuals require proportionately ''more'' dialysis than larger persons. The argument we present is congruent with outcome data as it relates to sex, race, and body size, as well as supportive of studies suggesting that certain groups (e.g., pregnant women, critically ill patients, diabetics) require greater dialysis delivery than the hemodialysis population in general.
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Ridel C, Osman D, Mercadal L, Anguel N, Petitclerc T, Richard C, Vinsonneau C. Ionic dialysance: a new valid parameter for quantification of dialysis efficiency in acute renal failure? Intensive Care Med 2007; 33:460-5. [PMID: 17235509 DOI: 10.1007/s00134-006-0514-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Accepted: 12/18/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVE Several studies have reported a close relationship between an increased dose of dialysis and survival in patients treated for acute renal failure. Unfortunately, the quantification of dialysis in critically ill patients based on the urea nitrogen formula Kt/V is not applicable. Ionic dialysance is a new parameter calculated in real time from the dialysate conductivity and correlated with the effective urea clearance in chronic hemodialysis patients. The aim of our study was to evaluate ionic dialysance in the quantification of dialysis in critically ill patients with acute renal failure. DESIGN Prospective open-label study. SETTING An 18-bed medical intensive care unit. PATIENTS Thirty-one patients with multiple organ dysfunction syndrome and acute renal failure requiring intermittent hemodialysis were included. MEASUREMENTS Using the first dialysis session of each patient, we compared the delivered dose of dialysis based on ionic dialysance measurement (Kt(ID)) with the well-accepted gold standard method based on fractional dialysate sampling (Kt(dialysate)). The data were analyzed using linear regression and Bland-Altman analysis. RESULTS Thirty-one intermittent hemodialysis sessions were performed in 31 critically ill patients (mean age 58+/-12 years, SAPS II score 56+/-10). We found a close correlation between Kt(dialysate) and Kt(ID) (Kt(dialysate) = 36.3+/-11.4 l; Kt(ID)=38.4+/-11.8; r=0.96) with excellent limits of agreement (-2.2 l; 6.4 l). CONCLUSION The feasibility of dialysis quantification based on ionic dialysance in the critically ill patient is good. This method is a simple and accurate tool for the determination of dialysis dose in critically ill patients.
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Affiliation(s)
- Christophe Ridel
- Service de Réanimation Médicale, Centre Hospitalo-Universitaire de Bicêtre, Assistance Publique-Hôpitaux de Paris, Université Paris XI, Le Kremlin-Bicêtre, Paris, France.
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