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Ehlerding G, Ries W, Kempkes-Koch M, Ziegler E, Ronová P, Krizsán M, Verešová J, Böke M, Erlenkötter A, Nitschel R, Zawada AM, Kennedy JP, Braun J, Larkin JW, Korolev N, Lang T, Ottillinger B, Stauss-Grabo M, Griesshaber B. Randomized investigation of increased dialyzer membrane hydrophilicity on hemocompatibility and performance. BMC Nephrol 2024; 25:220. [PMID: 38987671 PMCID: PMC11234537 DOI: 10.1186/s12882-024-03644-5] [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: 04/22/2024] [Accepted: 06/18/2024] [Indexed: 07/12/2024] Open
Abstract
BACKGROUND Hemodialyzers should efficiently eliminate small and middle molecular uremic toxins and possess exceptional hemocompatibility to improve well-being of patients with end-stage kidney disease. However, performance and hemocompatibility get compromised during treatment due to adsorption of plasma proteins to the dialyzer membrane. Increased membrane hydrophilicity reduces protein adsorption to the membrane and was implemented in the novel FX CorAL dialyzer. The present randomized controlled trial compares performance and hemocompatibility profiles of the FX CorAL dialyzer to other commonly used dialyzers applied in hemodiafiltration treatments. METHODS This prospective, open, controlled, multicentric, interventional, crossover study randomized stable patients on post-dilution online hemodiafiltration (HDF) to FX CorAL 600, FX CorDiax 600 (both Fresenius Medical Care) and xevonta Hi 15 (B. Braun) each for 4 weeks. Primary outcome was β2-microglobulin removal rate (β2-m RR). Non-inferiority and superiority of FX CorAL versus comparators were tested. Secondary endpoints were RR and/or clearance of small and middle molecules, and intra- and interdialytic profiles of hemocompatibility markers, with regards to complement activation, cell activation/inflammation, platelet activation and oxidative stress. Further endpoints were patient reported outcomes (PROs) and clinical safety. RESULTS 82 patients were included and 76 analyzed as intention-to-treat (ITT) population. FX CorAL showed the highest β2-m RR (76.28%), followed by FX CorDiax (75.69%) and xevonta (74.48%). Non-inferiority to both comparators and superiority to xevonta were statistically significant. Secondary endpoints related to middle molecules corroborated these results; performance for small molecules was comparable between dialyzers. Regarding intradialytic hemocompatibility, FX CorAL showed lower complement, white blood cell, and platelet activation. There were no differences in interdialytic hemocompatibility, PROs, or clinical safety. CONCLUSIONS The novel FX CorAL with increased membrane hydrophilicity showed strong performance and a favorable hemocompatibility profile as compared to other commonly used dialyzers in clinical practice. Further long-term investigations should examine whether the benefits of FX CorAL will translate into improved cardiovascular and mortality endpoints. TRIAL REGISTRATION eMPORA III registration on 19/01/2021 at ClinicalTrials.gov (NCT04714281).
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Affiliation(s)
- Götz Ehlerding
- Zentrum für Nieren-, Hochdruck- und Stoffwechselerkrankungen, 30453, Hannover, Germany
| | - Wolfgang Ries
- Diakonissenkrankenhaus, Innere Medizin, Abtlg. Nephrologie, 24939, Flensburg, Germany
| | | | | | - Petra Ronová
- Fresenius Nephrocare Praha 9, Praha, 19061, Czechia
| | - Mária Krizsán
- Péterfy II. Dialízis Központ, Budapest, 1077, Hungary
| | - Jana Verešová
- Fresenius Nephrocare Nymburk, Nymburk, 28802, Czechia
| | - Mária Böke
- Váci Dialízis Központ, Vác, 2600, Hungary
| | - Ansgar Erlenkötter
- Fresenius Medical Care Deutschland GmbH, Biosciences, VS Dialyzers, Care Enablement, 66606, St. Wendel, Germany
| | - Robert Nitschel
- Fresenius Medical Care Deutschland GmbH, Biosciences, VS Dialyzers, Care Enablement, 66606, St. Wendel, Germany
| | - Adam M Zawada
- Fresenius Medical Care Deutschland GmbH, Product Development, VS Dialyzers, Care Enablement, 66606, St. Wendel, Germany
| | - James P Kennedy
- Fresenius Medical Care Deutschland GmbH, Product Development, VS Dialyzers, Care Enablement, 66606, St. Wendel, Germany
| | - Jennifer Braun
- Fresenius Medical Care Deutschland GmbH, Global Biomedical Evidence Generation, Global Medical Office, 61352, Bad Homburg, Germany
| | - John W Larkin
- Fresenius Medical Care, Global Medical Office, Waltham, MA, USA
| | - Natalia Korolev
- Fresenius Medical Care Deutschland GmbH, Global Biomedical Evidence Generation, Global Medical Office, 61352, Bad Homburg, Germany
| | - Thomas Lang
- Fresenius Medical Care Deutschland GmbH, Global Biomedical Evidence Generation, Global Medical Office, 61352, Bad Homburg, Germany
| | | | - Manuela Stauss-Grabo
- Fresenius Medical Care Deutschland GmbH, Global Biomedical Evidence Generation, Global Medical Office, 61352, Bad Homburg, Germany
| | - Bettina Griesshaber
- Fresenius Medical Care Deutschland GmbH, Global Biomedical Evidence Generation, Global Medical Office, 61352, Bad Homburg, Germany.
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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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Ehlerding G, Ries W, Kempkes-Koch M, Ziegler E, Erlenkötter A, Zawada AM, Kennedy JP, Ottillinger B, Stauss-Grabo M, Lang T. Randomized comparison of three high-flux dialyzers during high-volume online hemodiafiltration—the comPERFORM study. Clin Kidney J 2021; 15:672-680. [PMID: 35464193 PMCID: PMC9022458 DOI: 10.1093/ckj/sfab196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Indexed: 11/24/2022] Open
Abstract
Background Dialyzers should be designed to efficiently eliminate uraemic toxins during dialysis treatment, given that the accumulation of small and middle molecular weight uraemic solutes is associated with increased mortality risk of patients with end-stage renal disease. In the present study we investigated the novel FX CorAL dialyzer with a modified membrane surface for performance during online hemodiafiltration (HDF) in a clinical setting. Methods comPERFORM was a prospective, open, controlled, multicentric, interventional, crossover study with randomized treatment sequences. It randomized stable patients receiving regular post-dilution online HDF to FX CorAL 600 (Fresenius Medical Care Deutschland), xevonta Hi 15 (B. Braun) and ELISIO 150H (Nipro) each for 1 week. The primary outcome was β2-m removal rate (β2-m RR) during online HDF. Secondary endpoints were RR and/or clearance of β2-m and other molecules. Albumin removal over time was an exploratory endpoint. Non-inferiority and superiority of FX CorAL 600 versus comparators were tested. Results Fifty-two patients were included and analysed. FX CorAL 600 showed the highest β2-m RR (75.47%), followed by xevonta Hi 15 (74.01%) and ELISIO 150H (72.70%). Superiority to its comparators was statistically significant (P = 0.0216 and P < 0.0001, respectively). Secondary endpoints related to middle molecules affirmed these results. FX CorAL 600 demonstrated the lowest albumin removal up to 60 minutes and its sieving properties changed less over time than with comparators. Conclusions FX CorAL 600 efficiently removed middle and small molecules and was superior to the two comparators in β2-m RR. Albumin sieving kinetics point to reduced formation of a secondary membrane.
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Affiliation(s)
- Götz Ehlerding
- Zentrum für Nieren-, Hochdruck- und Stoffwechselerkrankungen, Hannover, Germany
| | - Wolfgang Ries
- Diakonissenkrankenhaus, Innere Medizin, Abtlg. Nephrologie, Flensburg, Germany
| | | | | | - Ansgar Erlenkötter
- Fresenius Medical Care Deutschland, Global Research and Development, Biotechnology (WND), St. Wendel, Germany
| | - Adam M Zawada
- Fresenius Medical Care Deutschland, Global Research and Development, Product Engineering Center Dialyzers and Membranes, St. Wendel, Germany
| | - James P Kennedy
- Fresenius Medical Care Deutschland, Global Research and Development, Product Engineering Center Dialyzers and Membranes, St. Wendel, Germany
| | - Bertram Ottillinger
- Institut Dr Schauerte GbR (IDS), München, Germany
- Ottillinger Life Sciences, Brunnthal, Germany
| | - Manuela Stauss-Grabo
- Fresenius Medical Care Deutschland, Clinical Research, EMEA, AP & LA, Global Medical Office, Bad Homburg, Germany
| | - Thomas Lang
- Fresenius Medical Care Deutschland, Clinical Research, EMEA, AP & LA, Global Medical Office, Bad Homburg, Germany
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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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García Testal A, García Maset R, Fornés Ferrer V, Cañada Martínez AJ, Rico Salvador IS, Royo Maicas P, Fernández Najera JE, Olagüe Díaz P, Benedito Carrera C, Torregrosa De Juan E. Influential factors on dose by ionic dialysance in daily practice in chronic hemodialysis. Nephrol Ther 2021; 17:101-107. [PMID: 33461895 DOI: 10.1016/j.nephro.2020.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 11/24/2022]
Abstract
BACKGROUND The determination of Kt/V by ionic dialysance is a technique that has extended its use in hemodialysis clinics. The clinical guidelines have reflected the need to validate this method as a determinant of the dose of dialysis. OBJECTIVES Determine in daily practice, the influence of hemodialysis characteristics and medication on Kt/V results by ionic dialysance (Kt/V OCM) and compare them with Kt/V measures by serum urea (Kt/V Daugirdas). DESIGN Cross-sectional and observational study. PARTICIPANTS 127 patients on chronic hemodialysis. MEASUREMENTS Descriptive variables, study variables (Kt/VOCM, Kt/VDaugidas), and the variables that modified the effect (patient temperature, serum sodium, vascular access, recirculation, blood flow, hemodialysis technique, dialyzer, acid concentrate, conductivity, dialyzate flow). RESULTS The mean of Kt/V Daugirdas was 1.84 and the Kt/VOCM mean 1.65; Pearson's was CC r=0.54; P<0.001 and Lin CCC=0.48. In the linear regression, the variables related to hemodialysis technique showed no statistical association with the measurement obtained by Kt/VOCM. Monosodium phosphate and 20% sodium chloride dispensing were associated with a higher Kt/VOCM. CONCLUSIONS The different technical aspects noted during HD sessions do not influence Kt/V OCM outcomes. Kt/V determined by ionic dialysance isn't similar to that determined by serum urea. When assessing dialysis doses measured by dialysance, consider that it is not the same as determined with serum urea, but it provides an approximation to estimate dialysis doses in real time. It is necessary to consider if drugs or supplements have been administered that can modify it when interpreting the results.
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Affiliation(s)
- Alicia García Testal
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain.
| | - Rafael García Maset
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain
| | | | | | | | - Pilar Royo Maicas
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain
| | - Jose Enrique Fernández Najera
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain
| | - Pau Olagüe Díaz
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain
| | - Caterina Benedito Carrera
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain
| | - Eduardo Torregrosa De Juan
- Department of Nephrology, hemodiálisis Hospital de Manises, avenida Generalitat Valenciana 50, 46940 Manises Valencia, Spain
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Szamosfalvi B, Heung M, Yessayan L. Technology Innovations in Continuous Kidney Replacement Therapy: The Clinician's Perspective. Adv Chronic Kidney Dis 2021; 28:3-12. [PMID: 34389135 DOI: 10.1053/j.ackd.2021.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/25/2021] [Accepted: 03/27/2021] [Indexed: 11/11/2022]
Abstract
Continuous kidney replacement therapy (CKRT) has improved remarkably since its first implementation as continuous arteriovenous hemofiltration in the 1970s. However, when looking at the latest generation of CKRT machines, one could argue that clinical deployment of breakthrough innovations by device manufacturers has slowed in the last decade. Simultaneously, there has been a steady accumulation of clinical knowledge using CKRT as well as a multitude of therapeutic and diagnostic innovations in the dialysis and broader intensive care unit technology fields adaptable to CKRT. These include multiple different anticlotting measures; cloud-computing for optimized treatment prescribing and delivered therapy data collection and analysis; novel blood purification techniques aimed at improving the severe multiorgan dysfunction syndrome; and real-time sensing of blood and/or filter effluent composition. The authors present a view of how CKRT devices and programs could be reimagined incorporating these innovations to achieve specific measurable clinical outcomes with personalized care and improved simplicity, safety, and efficacy of CKRT therapy.
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Raimann JG, Ye X, Kotanko P, Daugirdas JT. Routine Kt/V and Normalized Protein Nitrogen Appearance Rate Determined From Conductivity Access Clearance With Infrequent Postdialysis Serum Urea Nitrogen Measurements. Am J Kidney Dis 2020; 76:22-31. [PMID: 32220509 DOI: 10.1053/j.ajkd.2019.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 12/23/2019] [Indexed: 11/11/2022]
Abstract
RATIONALE & OBJECTIVES Conventional monitoring of hemodialysis dose is implemented using urea kinetic modeling based on single-pool Kt/V, which requires both pre- and postdialysis serum urea nitrogen (SUN) measurements. We compared this conventional approach to one in which Kt/V is calculated using conductivity clearance, thereby reducing the need for regular postdialysis SUN measurements. STUDY DESIGN Comparative study of 2 diagnostic tests. SETTING & PARTICIPANTS Prevalent patients receiving maintenance hemodialysis for at least 2 years for whom both urea reduction ratio (URR) and average conductivity clearance (Kecn) were measured. TESTS COMPARED During the initial 8 months (baseline interval), average Kecn and URR were used to calculate a median patient-specific, modeled, calibration solute distribution volume (Vcal). During months 9 to 16 (period 1) and 17 to 24 (period 2), Kt/V was conventionally computed using URR and also by a new method using Vcal and Kecn without postdialysis SUN values. We examined the percentage error between these 2 methods of calculating Kt/V. OUTCOMES Concordance between the 2 methods of calculating Kt/V. RESULTS Among 1,093 patients, mean individual-level median single-pool Kt/V values derived using the conventional method during the baseline interval, period 1, and period 2 were 1.62±0.24 (SD), 1.66±0.24, and 1.67±0.24, respectively. During periods 1 and 2, patient-level median Kt/V values derived using Kecn were 1.64±0.24 and 1.65±0.24, respectively. Percent differences between patient-level median values of Kt/V (conductivity minus conventional URR methods) were-0.63%±7.7% and-0.75%±8.4% for periods 1 and 2. Normalized protein nitrogen appearance were comparable between the 2 methods. LIMITATIONS Data were collected over 2 years. Study was limited to in-center hemodialysis patients dialyzed 3 times per week. Dialysis session length was not adjusted for treatment interruptions. CONCLUSIONS A new method of calculating Kt/V based on Kecn that requires fewer postdialysis SUN measurements provided diagnostic data comparable to those from conventional use of URR and has the potential to avoid errors related to postdialysis blood sampling and measurement.
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Affiliation(s)
| | - Xiaoling Ye
- Research Division, Renal Research Institute, New York, NY
| | - Peter Kotanko
- Research Division, Renal Research Institute, New York, NY; Icahn School of Medicine at the Mount Sinai Hospital, New York, NY
| | - John T Daugirdas
- Division of Nephrology, Department of Medicine, University of Illinois College of Medicine, Chicago, IL.
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Cheng YL, Tang HL, Tong MKL. Clinical practice guidelines for the provision of renal service in Hong Kong: Haemodialysis. Nephrology (Carlton) 2019; 24 Suppl 1:41-59. [DOI: 10.1111/nep.13498] [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]
Affiliation(s)
- Yuk Lun Cheng
- Department of MedicineAlice Ho Miu Ling Nethersole Hospital Hong Kong
| | - Hon Lok Tang
- Renal Unit, Department of Medicine & GeriatricsPrincess Margaret Hospital Hong Kong
| | - Matthew Kwok Lung Tong
- Renal Unit, Department of Medicine & GeriatricsPrincess Margaret Hospital Hong Kong
- Renal Dialysis Centre, Hong Kong Sanatorium & Hospital Hong Kong
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Daugirdas JT. Eliminating the need for routine monthly postdialysis serum urea nitrogen measurement: A method for monitoring Kt/V and normalized protein catabolic rate using conductivity determined dialyzer clearance. Semin Dial 2018; 31:633-636. [PMID: 30311270 DOI: 10.1111/sdi.12750] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many dialysis machines can compute dialyzer sodium clearances at multiple time points during a dialysis treatment using conductivity. For a given treatment, the average dialyzer sodium clearance (K), when combined with treatment time (t), and the estimated urea distribution volume (V, usually based on either anthropometry or bioimpedance), can be used to estimate Kt/V, an important measure of hemodialysis adequacy. While this conductivity-derived value for Kt/V correlates moderately with Kt/V calculated from predialysis and postdialysis serum urea nitrogen (SUN) values (urea reduction ratio, URR), the ultrafiltration volume, and session length it is, unfortunately, not sufficiently accurate to replace URR-based Kt/V. Here we underline the potential utility of an alternative method to estimate Kt/V (a variant of a technique originally proposed by Gotch and Levin and their colleagues) using conductivity-derived sodium clearance (K) that does not require routine measurement of the postdialysis SUN but which should closely track Kt/V computed in the usual fashion. The increased accuracy with the new method is explained by the use of a patient-specific value of V, which is an average value calculated from several dialysis sessions where both conductivity dialyzer clearance and predialysis and postdialysis SUN have been measured. Once this patient-specific conductivity/URR-based value for V has been determined, it can be used to calculate Kt/V for subsequent treatments in which conductivity-based dialyzer clearances are measured, but around which predialysis and postdialysis SUN values have not been obtained. (If the predialysis SUN values for such a subsequent treatment are also measured, then a normalized protein catabolic rate that closely tracks the value from conventional urea modeling, can also be determined.) By reducing the number of postdialysis SUN measurements needed to monitor hemodialysis adequacy this new method of estimating Kt/V by conductivity should save staff time and laboratory costs, increase patient and staff safety, and decrease error rates associated with improper postdialysis blood sampling technique.
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Affiliation(s)
- John T Daugirdas
- Division of Nephrology, Department of Medicine, University of Illinois College of Medicine at Chicago, Chicago, Illinois
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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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Aslam S, Saggi SJ, Salifu M, Kossmann RJ. Online measurement of hemodialysis adequacy using effective ionic dialysance of sodium-a review of its principles, applications, benefits, and risks. Hemodial Int 2017; 22:425-434. [PMID: 29210176 DOI: 10.1111/hdi.12623] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Dialysis dose is an important determinant of clinical outcomes in patients with end stage renal disease on maintenance dialysis. In clinical practice dialysis dose is monitored at least monthly by urea clearance based on Urea Kinetic Modeling. Online clearance monitoring using effective ionic dialysance (EID) of sodium (Na+ ) is available on some hemodialysis machines. This paper reviews the background, methodology, additional applications, and potential risks associated with EID. Effective ionic dialysance provides a reliable, real-time, noninvasive, and inexpensive measurement of dialysis dose during an ongoing hemodialysis (HD) session to allow interventions and assess the impact of these changes on clearance. Surveillance of vascular access flow rates can be used to screen for access dysfunction and refer for interventions. There is a concern that EID measurements may cause Na+ loading because of high dialysate Na+ used during these measurements, however, mathematical models, in vitro experiments, and clinical studies in patients on maintenance HD do not show any evidence of Na+ loading during EID measurements. We cannot rule out the possibility of nonosmotic Na+ accumulation in the skin because no published literature exists on this topic as it pertains to clearance measurements based on EID of Na+ .
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Affiliation(s)
- Shakil Aslam
- Fresenius Medical Care of North America, Renal Therapies Group, Waltham, Massachusetts, USA
| | - Subodh J Saggi
- Division of Nephrology, State University of New York-Health Sciences Center at Brooklyn, Brooklyn, New York, USA
| | - Moro Salifu
- Division of Nephrology, State University of New York-Health Sciences Center at Brooklyn, Brooklyn, New York, USA
| | - Robert J Kossmann
- Fresenius Medical Care of North America, Renal Therapies Group, Waltham, Massachusetts, USA
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Hamdi T, Yessayan L, Yee J, Szamosfalvi B. High sodium continuous veno-venous hemodialysis with regional citrate anticoagulation and online dialysate generation in patients with acute liver failure and cerebral edema. Hemodial Int 2017; 22:184-191. [DOI: 10.1111/hdi.12572] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Tamim Hamdi
- Department of Internal Medicine, Division of Nephrology; UT Southwestern; Dallas TX USA
| | - Lenar Yessayan
- Department of Internal Medicine, Division of Nephrology; University of Michigan; Ann Arbor MI USA
| | - Jerry Yee
- Department of Internal Medicine, Division of Nephrology; Henry Ford Hospital; Detroit MI USA
| | - Balazs Szamosfalvi
- Department of Internal Medicine, Division of Nephrology; University of Michigan; Ann Arbor MI USA
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Sharma MK, Wieringa FP, Frijns AJH, Kooman JP. On-line monitoring of electrolytes in hemodialysis: on the road towards individualizing treatment. Expert Rev Med Devices 2016; 13:933-943. [DOI: 10.1080/17434440.2016.1230494] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Manoj K. Sharma
- Department of Mechanical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Fokko P. Wieringa
- TNO Science & Industry, Division of Medical Equipment, Delft, Netherlands
- Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Arjan J. H. Frijns
- Department of Mechanical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Jeroen P. Kooman
- Department of Internal Medicine, Division of Nephrology, University Hospital Maastricht, Maastricht, Netherlands
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Daugirdas JT, Depner TA, Inrig J, Mehrotra R, Rocco MV, Suri RS, Weiner DE, Greer N, Ishani A, MacDonald R, Olson C, Rutks I, Slinin Y, Wilt TJ, Rocco M, Kramer H, Choi MJ, Samaniego-Picota M, Scheel PJ, Willis K, Joseph J, Brereton L. KDOQI Clinical Practice Guideline for Hemodialysis Adequacy: 2015 Update. Am J Kidney Dis 2015; 66:884-930. [DOI: 10.1053/j.ajkd.2015.07.015] [Citation(s) in RCA: 603] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 07/31/2015] [Indexed: 12/13/2022]
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Kraemer M. Physiological monitoring and control in hemodialysis: state of the art and outlook. Expert Rev Med Devices 2014; 3:617-34. [PMID: 17064247 DOI: 10.1586/17434440.3.5.617] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Medical devices for monitoring and feedback control of physiological parameters of the dialysis patient were introduced in the early 1990s. They have a wide range of applications, aiming at increasing the safety and ensuring the efficiency of the treatment, and at an improved restoration of physiological conditions, leading to an overall reduction in morbidity and mortality. Such devices include sensors for the measurement of temperature, optical parameters and sound speed in blood, and electrical characteristics of the human body, and other parameters. Essential for the development of these devices is a detailed understanding of the pathophysiological background of a therapeutical problem. There is still a large potential to introduce new devices for further therapy improvement and automation. Also, the size of the hemodialysis market appears attractive; however, a new product has to meet several specific requirements in order to also become commercially successful. This review describes the therapeutic and technical principles of several available devices, reports on concepts for possible future devices, and presents a short overview on the market environment.
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Affiliation(s)
- Matthias Kraemer
- Fresenius Biotech GmbH, Borkenberg 14, 61440 Oberursel, Germany.
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Polaschegg HD. Hemodialysis machine technology: a global overview. Expert Rev Med Devices 2014; 7:793-810. [DOI: 10.1586/erd.10.54] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Alayoud A, Montassir D, Hamzi A, Zajjari Y, Bahadi A, Kabbaj DE, Maoujoud O, Aatif T, Hassani K, Benyahia M, Oualim Z. The Kt/V by ionic dialysance: Interpretation limits. Indian J Nephrol 2013; 22:333-9. [PMID: 23326042 PMCID: PMC3544053 DOI: 10.4103/0971-4065.103906] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The availability of hemodialysis machines equipped with online clearance monitoring (OCM) allows frequent assessment of dialysis efficiency and adequacy without the need for blood samples. Accurate estimation of the urea distribution volume (V) is required for Kt/V calculated from OCM to be consistent with conventional blood sample-based methods. A total of 35 patients were studied. Ionic dialysance was measured by conductivity monitoring. The second-generation Daugirdas formula was used to calculate the Kt/V single-pool (Kt/VD). Values of V to allow comparison between OCM and blood-based Kt/V were determined using Watson formula (VWa), bioimpedance spectroscopy (Vimp), and blood-based kinetic data (Vukm). Comparison of Kt/Vw ocm calculated by the ionic dialysance and Vw (Kt/Vw ocm) with Kt/VD shows that using VW leads to significant systematic underestimation of dialysis dose by 24%. Better agreement between Kt/V ocm and Kt/VD was observed when using Vimp and Vukm. Bio-impedancemetry and the indirect method using the second-generation Daugirdas equation are two methods of clinical interest for estimating V to ensure greater agreement between OCM and blood-based Kt/V.
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Affiliation(s)
- A Alayoud
- Service of Nephrology, Dialysis and Kidney Transplantation, Military Hospital of Instruction, Mohammed V Rabat, Morocco
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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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Szamosfalvi B, Frinak S, Yee J. Sensors and Hybrid Therapies: A New Approach with Automated Citrate Anticoagulation. Blood Purif 2012; 34:80-7. [DOI: 10.1159/000341644] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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20
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Urea kinetics and intermittent dialysis prescription in small animals. Vet Clin North Am Small Anim Pract 2011; 41:193-225. [PMID: 21251518 DOI: 10.1016/j.cvsm.2010.12.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hemodialysis improves survival for animals with acute kidney injury beyond what would be expected with conventional management of the same animals. Clinical evidence and experience in human patients suggest a role for earlier intervention with renal replacement to avoid the morbidity of uremia and to promote better metabolic stability and recovery. For a large population of animal patients, it is the advanced standard for the management of acute and chronic uremia, life-threatening poisoning, and fluid overload for which there is no alternative therapy.
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Effective Ionic Dialysance/Blood Flow Rate Ratio: An Indicator of Access Recirculation in Arteriovenous Fistulae. ASAIO J 2010; 56:427-33. [DOI: 10.1097/mat.0b013e3181e743eb] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Real-time Kt/V determination by ultraviolet absorbance in spent dialysate: technique validation. Kidney Int 2010; 78:920-5. [PMID: 20631678 DOI: 10.1038/ki.2010.216] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Real-time determination of Kt/V can be provided by monitoring ultraviolet absorbance of solutes in spent dialysate. This not only overcomes dependency on error-prone pre- and post-dialysis blood sampling; it circumvents inaccuracies associated with estimating the urea distribution volume and its high measurement frequency tightly reflects the course of the dialysis. Our study compared the ultraviolet-based spKt/V and eKt/V with the commonly used blood-based counterparts. A first study of 16 patients compared ultraviolet Kt/Vs against blood Kt/Vs obtained by using the 'gold standard' of serial blood samples. A second study included 18 patients and compared the ultraviolet and blood values under routine conditions. Both studies showed mean blood-based spKt/V and eKt/V values statistically indistinguishable from their ultraviolet-based counterparts. Hence, on-line monitoring of ultraviolet absorption of spent dialysate is applicable in routine hemodialysis allowing continuous measure of removed solutes from spent dialysate without disturbing the patient or treatment session.
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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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Schneditz D, Platzer D, Daugirdas JT. A diffusion-adjusted regional blood flow model to predict solute kinetics during haemodialysis. Nephrol Dial Transplant 2009; 24:2218-24. [DOI: 10.1093/ndt/gfp023] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lin YF, Huang JW, Wu MS, Chu TS, Lin SL, Chen YM, Tsai TJ, Wu KD. Comparison of residual renal function in patients undergoing twice-weekly versus three-times-weekly haemodialysis. Nephrology (Carlton) 2008; 14:59-64. [PMID: 19019171 DOI: 10.1111/j.1440-1797.2008.01016.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM Patients with end-stage renal disease (ESRD) often start long-term haemodialysis (HD) thrice weekly, regardless of the level of residual renal function (RRF). In this study, we investigated whether ESRD patients having sufficient RRF can be maintained on twice-weekly HD, and how they fare compared to patients without RRF on thrice-weekly HD. METHODS We analyzed 74 patients who had undergone long-term HD and maintained on the same dialysis frequency from February 1998 to July 2005, and followed until December 2005. We compared the clinical variables between twice-weekly and thrice-weekly HD patients and a second analysis testing the residual urine output as an independent predictor for twice-weekly HD. RESULTS After a mean follow up of 18 months, twice-weekly HD patients (n = 23) had lower serum beta2-microglobulin than thrice-weekly HD patients (n = 51). Moreover, the twice-weekly group had a slower decline of RRF, as indicated by their higher urine output and creatinine clearance, fewer intradialytic hypotensive episodes, and required less frequent hospitalization. There was no difference between the two groups in cardiothoracic ratio or indices of nutrition and inflammation. Multivariable logistic regression identified age (odds ratio (OR), 1.866; 95% CI, 1.093-3.183), dry body mass index (OR, 0.790; 95% CI, 0.625-0.999), and urine output (OR, 1.093; 95% CI, 1.026-1.164) as predictors for maintaining twice-weekly HD. CONCLUSION Our data suggest that when patients who have sufficient urine output are given twice-weekly HD, they maintain dialysis adequacy and exhibit better preservation of RRF than patients on thrice-weekly HD.
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Affiliation(s)
- Yu-Feng Lin
- Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin and National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
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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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28
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Schneditz D. The Convertibility of Online Clearance Measurements. Am J Kidney Dis 2008; 52:7-9. [DOI: 10.1053/j.ajkd.2008.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2008] [Accepted: 05/16/2008] [Indexed: 11/11/2022]
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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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Hoenich NA, Levin NW. Hemodialysis machines. Biomed Instrum Technol 2007; 41:215-8. [PMID: 17582956 DOI: 10.2345/0899-8205(2007)41[215:hm]2.0.co;2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Affiliation(s)
- Nicholas A Hoenich
- School of Clinical Medical Sciences, Newcastle University, United Kingdom
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Petitclerc T. Do dialysate conductivity measurements provide conductivity clearance or ionic dialysance? Kidney Int 2006; 70:1682-6. [PMID: 16985517 DOI: 10.1038/sj.ki.5001840] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Dialysate conductivity measurements allow on-line estimation of urea clearance during hemodialysis session. Conductivity measurements provide a value of 'conductivity clearance' for some authors, but a value of 'ionic dialysance' for others. This paper aims at explaining which term should be the more appropriate. Clearance is a parameter defined for measuring the power of a mechanism, which aims at 'clearing' a solution by depurating some solutes. In hemodialysis, clearance measures the efficacy of patient's depuration. In contrast, dialysance measures the capability of transferring solutes between blood and dialysate. The conventional definition of dialysance, requiring the absence of convective transfer, should be generalized to the case of the usual presence of ultrafiltration during the hemodialysis session. For a solute (as urea) absent from the dialysate delivered to the dialyzer inlet, the clearance is equal to its dialysance. In order to avoid a dramatic fall in ionic concentrations during hemodialysis treatment, the clearance of ions is reduced by adding these ions in the dialysate and becomes lower than their dialysance. Conductivity measurements provide a value of electrolytes dialysance. Thus the term of 'ionic dialysance' is more appropriate than the term of 'conductivity clearance'. Nevertheless ionic dialysance represents a good estimation of urea clearance.
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Affiliation(s)
- T Petitclerc
- Department of Biophysics, University Pierre et Marie Curie, and Hemodialysis Units, AURA, Paris, France.
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Lowrie EG, Li Z, Ofsthun NJ, Lazarus JM. Evaluating a new method to judge dialysis treatment using online measurements of ionic clearance. Kidney Int 2006; 70:211-7. [PMID: 16723982 DOI: 10.1038/sj.ki.5001507] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
New technology now supports direct online measurements of total dialysis dose per treatment, Kt. An outcome-based, nonlinear method for estimating target Kt in terms of ionic clearance measurements and body surface area (BSA) has been described recently. This is a validation study of the new method that evaluates the relationship between the (actual Kt-target Kt) difference and death risk. Patients with Kt measurements during March 2004 were identified (N=59,644). Target Kt was determined for each patient using the new method. Patients were then grouped by (actual Kt-target Kt) decile. They were also grouped by (actual URR-target URR) decile. Cox analysis-based risk profiles were constructed using those groupings. The (actual Kt-target Kt) difference profiles suggested improving death risk as Kt increased from below target to equal target. Risk ratios then flattened and remained so until (actual Kt-target Kt) reached the highest decile at which it appeared to improve, suggesting a possible biphasic profile. The (URR-target URR) risk profile was U-shaped. Death risk was related to the difference between the actual Kt and a target Kt value selected using the new nonlinear method. The method is therefore valid for prescribing and monitoring hemodialysis treatment.
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Affiliation(s)
- E G Lowrie
- Fresenius Medical Care North America, Lexington, Massachusetts, USA.
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Abstract
Salt and water are the major components of extracellular fluid, and each patient on dialysis has a unique serum sodium activity that is defended to ensure homeostasis. Dialysate use that does not restore extracellular composition to its equilibrium value results in disequilibrium and affects dialysis discomfort, blood pressure, thirst, and weight gain. When dialysate sodium activity exceeds the dialyzable plasma sodium activity, sodium diffuses from the dialysate into the patient. This results in hypertonicity, cellular dehydration, plasma volume expansion, and hypertension. A dialysate sodium activity below the patient's dialyzable plasma sodium reverses this process. Neither of these situations is desirable. Rather, dialysis should restore homeostasis by reconstituting the extracellular fluid to its desired salt and water content. Because each patient has a unique serum sodium activity, this goal can only be realized by using individualized dialysate sodium prescriptions. Further, because a patient's dialyzable sodium is dynamic and determined by serum chemistry plus dialyzer membrane behavior, the dialysate sodium needed to achieve isonatemic dialysis can only be defined by measuring the dialyzable serum sodium activity during dialysis. Achieving balanced salt and water removal to preserve homeostasis and intracellular tonicity requires automated sensors and feed-back control of dialysate conductivity.
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Affiliation(s)
- Michael J Flanigan
- Nephrology Division, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
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Di Filippo S, Pozzoni P, Manzoni C, Andrulli S, Pontoriero G, Locatelli F. Relationship between urea clearance and ionic dialysance determined using a single-step conductivity profile. Kidney Int 2005; 68:2389-95. [PMID: 16221245 DOI: 10.1111/j.1523-1755.2005.00702.x] [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] [Indexed: 11/30/2022]
Abstract
BACKGROUND On-line determination of ionic dialysance (ID) has been used to measure the clearance of small solutes like urea. However, attempts to determine the in vivo relationship between ID and urea clearance have led to discordant findings. The aim of this study was to determine the relationship between the mean values of repeated instantaneous determinations of ID throughout a dialysis session ((m)ID), obtained using a single-step inlet dialysate conductivity profile, and the mean values of urea clearance corrected for access recirculation (K(eu1)), total recirculation (access plus cardiopulmonary recirculation, K(eu2)), and the entire postdialysis urea rebound (K(wb)). METHODS Eighty-two anuric patients on chronic thrice-weekly hemodialysis were studied using an Integra machine equipped with the Diascan module for the automatic determination of ID. The mean values of repeated ID measurements made at 30-minute intervals were compared with K(eu1) (available for only 31 patients), K(eu2), and K(wb). RESULTS The results in all 82 patients were: (m)ID = 176 +/- 23 mL/min; K(eu2) = 181 +/- 25 mL/min; K(wb) = 159 +/- 22 mL/min. The mean (m)ID/K(wb) and (m)ID/K(eu2) ratios were, respectively, 1.11 +/- 0.06 and 0.98 +/- 0.06. The results in the 31 patients for whom K(eu1) values were available were: (m)ID = 179 +/- 24 mL/min and K(eu1) = 200 +/- 27 mL/min; the mean (m)ID/K(eu1) ratio was 0.90 +/- 0.05. CONCLUSION The mean value of repeated ID determinations obtained using a single-step conductivity profile underestimates urea clearance corrected for access recirculation, and may be considered an adequate estimate of urea clearance corrected for total recirculation.
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Depner TA. Hemodialysis adequacy: basic essentials and practical points for the nephrologist in training. Hemodial Int 2005; 9:241-54. [PMID: 16191074 DOI: 10.1111/j.1492-7535.2005.01138.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thomas A Depner
- Nephrology Division, University of California at Davis, Davis, California, USA.
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Lowrie EG, Li Z, Ofsthun N, Lazarus JM. The online measurement of hemodialysis dose (Kt): Clinical outcome as a function of body surface area. Kidney Int 2005; 68:1344-54. [PMID: 16105070 DOI: 10.1111/j.1523-1755.2005.00533.x] [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: 12/18/2022]
Abstract
BACKGROUND Recent advances enable the direct measurement of small molecule clearance, Kecn, during each dialysis. Average Kecn and treatment length, t, are multiplied giving total clearance, Kt. The body surface area (BSA) is a fixed transformation of height and weight and is a well recognized measure of body size. This project was conceived to search for clinical outcome-based functions for measured Kt in terms of BSA to enable simple Kt prescription guidelines for clinicians who are able to measure Kecn, and to provide foundations for future clinical research. METHODS The data came from Fresenius Medical Care (NA) files and included more than 32,000 patients with height, weight, and paired Kecn and t measurements during December 2002. Measurements were averaged for the month and used as predictor measures in Cox models of survival time during 2003. Candidate Kt values from 30 L/treatment through 70 were examined to determine the best statistical fit for quintile and decile delimited BSA groups evaluating the best fit Kt treatment target for each group. Functional forms representing the relationship between target Kt values and mean BSA of the groups were then evaluated to determine the best fit. RESULTS Kt targets increased with BSA in a curvilinear way such that the rate of increase is greater at low BSA than high. The best statistical fit was a double reciprocal form, Kt = 1/(a + b/BSA); "a" and "b" are statistically derived coefficients. The form has an appealing mathematical property; Kt approaches 0 as BSA approaches 0. Other forms fit the data nearly as well, however, and can be used to estimate Kt targets for patients with different BSA. CONCLUSION Empirical, outcome-based functions of measured Kt in terms of BSA exist and can be used as aids for prescribing and judging hemodialysis treatment.
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Affiliation(s)
- Edmund G Lowrie
- Health Information Systems, Fresenius Medical Care (North America), Lexington, Massachusetts 02420-9192, USA.
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Mercadal L, Ridel C, Petitclerc T. Ionic dialysance: Principle and review of its clinical relevance for quantification of hemodialysis efficiency. Hemodial Int 2005; 9:111-9. [PMID: 16191058 DOI: 10.1111/j.1492-7535.2005.01122.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Ionic dialysance (D) is an online measured variable now available on several dialysis monitors to evaluate small-solute clearance. Based on conductivity measurements in the inlet and outlet dialysate, the principle of the measurement and the different measurement methods are described. Studies that have evaluated the reliability of ionic dialysance to assess dialysis efficiency are discussed. These studies are divided into two groups: the first comparing ionic dialysance to urea clearance and the second comparing Dt/V to Kt/V(urea), in which the uncertainties of the measurement of V(urea) could have misrepresented the relationship between Dt/V and Kt/V(urea). When Kt/V(urea) via the Daugirdas second-generation equation taking the rebound into account is considered, slight-even nonsignificant-differences are evidenced between Kt/V(urea) and Dt/V. Therefore, ionic dialysance should be considered as a valid measure in future guidelines for dialysis efficiency.
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Affiliation(s)
- Lucile Mercadal
- Department of Nephrology, Pitié-Salpétrière Hospital, Paris, France.
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