1
|
Casino FG, Mancini E, Santarsia G, Mostacci SD, D'Elia F, Di Carlo M, Iannuzzella F, Rossi L, Vernaglione L, Grimaldi D, Rapanà R, Basile C. What volume to choose to assess online Kt/V? J Nephrol 2019; 33:137-146. [PMID: 31392658 DOI: 10.1007/s40620-019-00636-9] [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: 05/12/2019] [Accepted: 07/31/2019] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Urea distribution volume (V) can be assessed in different ways, among them the anthropometric Watson Volume (VW). However, many studies have shown that VW does not coincide with V and that the latter can be more accurately estimated with other methods. The present multicentre study was designed to answer the question: what V to choose to assess online Kt/V? MATERIALS AND METHODS Pre- and postdialysis blood urea nitrogen concentrations and the usual input data set for urea kinetic modelling were obtained for a single dialysis session in 201 Caucasian patients treated in 9 Italian dialysis units. Only dialysis machines measuring ionic dialysance (ID) were utilized. ID reflects very accurately the mean effective dialyser urea clearance (Kd). Six different V values were obtained: the first one was VW; the second one was computed from the equation established by the HEMO Study to predict the single pool-adjusted modelled V from VW (VH) (Daugirdas JT et al. KI 64: 1108, 2003); the others were estimated kinetically as: 1. V_ID, in which ID is direct input in the in the double pool variable volume (dpVV) calculation by means of the Solute-solver software; 2. V_Kd, in which the estimated Kd is direct input in the dpVV calculation by means of the Solute-solver software; 3. V_KTV, in which V is calculated by means of the second generation Daugirdas equation; 4. V_SPEEDY, in which ID is direct input in the dpVV calculation by means of the SPEEDY software able to provide results quite similar to those provided by Solute-solver. RESULTS Mean± SD of the main data are reported: measured ID was 190.6 ± 29.6 mL/min, estimated Kd was 211.6 ± 29.0 mL/min. The relationship between paired data was poor (R2 = 0.34) and their difference at the Bland-Altman plot was large (21 ± 27 mL/min). VW was 35.3 ± 6.3 L, VH 29.5 ± 5.5, V_ID 28.99 ± 7.6 L, V_SPEEDY 29.4 ± 7.6 L, V_KTV 29.7 ± 7.0 L. The mean ratio VW/V_ID was 1.22, (i.e. VW overestimated V_ID by about 22%). The mean ratio VH/V_ID was 1.02 (i.e. VH overestimated V_ID by only 2%). The relationship between paired data of V_ID and VW was poor (R2 = 0.48) and their mean difference at the Bland-Altman plot was very large (- 6.39 ± 5.59 L). The relationship between paired data of V_ID and VH was poor (R2 = 47) and their mean difference was small but with a large SD (- 0.59 ± 5.53 L). The relationship between paired data of V_ID and V_SPEEDY was excellent (R2 = 0.993) and their mean difference at the Bland-Altman plot was very small (- 0.54 ± 0.64 L). The relationship between paired data of V_ID and V_KTV was excellent (R2 = 0.985) and their mean difference at the Bland-Altman plot was small (- 0.85 ± 1.06 L). CONCLUSIONS V_ID can be considered the reference method to estimate the modelled V and then the first choice to assess Kt/V. V_SPEEDY is a valuable alternative to V_ID. V_KTV can be utilized in the daily practice, taking also into account its simple way of calculation. VW is not advisable because it leads to underestimation of Kt/V by about 20%.
Collapse
Affiliation(s)
- Francesco Gaetano Casino
- Clinical Research Branch, Division of Nephrology, Miulli General Hospital, Acquaviva delle Fonti, Italy.,Dialysis Centre SM2, Policoro, Italy
| | | | | | | | | | | | | | - Luigi Rossi
- Clinical Research Branch, Division of Nephrology, Miulli General Hospital, Acquaviva delle Fonti, Italy
| | | | | | | | - Carlo Basile
- Clinical Research Branch, Division of Nephrology, Miulli General Hospital, Acquaviva delle Fonti, Italy. .,Associazione Nefrologica Gabriella Sebastio, Via Battisti 192, 74121, Taranto, Martina Franca, Italy.
| |
Collapse
|
2
|
Gebregeorgis W, Bhat ZY, Pradhan N, Migdal SD, Nandagopal L, Singasani R, Mushtaq T, Thomas R, Osman Malik YM. Correlation between Dt/V derived from ionic dialysance and blood-driven Kt/V of urea in African-American hemodialysis patients, based on body weight and ultrafiltration volume. Clin Kidney J 2018; 11:734-741. [PMID: 30288271 PMCID: PMC6165765 DOI: 10.1093/ckj/sfx155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/04/2017] [Indexed: 11/14/2022] Open
Abstract
Background The Dt/V obtained by using ionic dialysance (D) as a surrogate for urea clearance (K) is a well-validated adjunct measure of hemodialysis adequacy, with a variable level of correlation with urea-based Kt/V. However, this correlation has not been examined based on patients’ body size and ultrafiltration (UF) volume during the dialysis session. Methods Simultaneous evaluations of online Dt/V and single-pool variable-volume urea Kt/V were made. Patients were categorized into three subgroups based on their weight (<60, 60–80 and ≥80 kg), body mass index (<25, 25–30 and >30 kg/m2) and UF volume (<1.5, 1.5–3 and >3 L). The correlation between Dt/V and Kt/V was evaluated for the entire cohort per dialysis session in each subgroup. Results Mean Kt/V was greater than the mean Dt/V (1.72 versus 1.50, P < 0.001), with an overall correlation r value of 0.602. This correlation was stronger in the medium weight group versus lower and higher weights. The correlation between Dt/V and Kt/V was inversely related to the UF volume (r = 0.698, 0.621 and 0.558 for those with UF volume of <1.5, 1.5–3.0 and >3 L, respectively). A total of 99.3% of patients with Dt/V of >1.2 also had Kt/V >1.2 and 9.5% of those with Dt/V <1.2 had their Kt/V <1.2. Conclusions There is a moderate degree of correlation between Dt/V and Kt/V in African-American hemodialysis patients, which is impacted by body size and UF volume. A Dt/V of >1.2 strongly predicts adequate dialysis as defined by Kt/V of >1.2.
Collapse
Affiliation(s)
- Wihib Gebregeorgis
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | - Zeenat Yousuf Bhat
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | - Nishigandha Pradhan
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | - Stephen D Migdal
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | - Lakshminarayanan Nandagopal
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | | | - Tehmina Mushtaq
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | - Ronald Thomas
- Children's Research Center of Michigan, Department of Pediatrics, Wayne State University School of Medicine, Detroit, MI, USA
| | - Yahya M Osman Malik
- Division of Nephrology and Hypertension, Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| |
Collapse
|
3
|
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.
Collapse
Affiliation(s)
- Aarne Vartia
- Retired from Savonlinna Central Hospital, Savonlinna, Finland
| |
Collapse
|
4
|
di Filippo S, Carfagna F, la Milia V, Bellasi A, Casagrande G, Bianchi C, Vito D, Costantino ML, Rombolà G, Minoretti C, Schönholzer C, Pontoriero G, Locatelli F. Assessment of intradialysis calcium mass balance by a single pool variable-volume calcium kinetic model. Hemodial Int 2017; 22:126-135. [PMID: 28164430 DOI: 10.1111/hdi.12531] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION A reliable method of intradialysis calcium mass balance quantification is far from been established. We herein investigated the use of a single-pool variable-volume Calcium kinetic model to assess calcium mass balance in chronic and stable dialysis patients. METHODS Thirty-four patients on thrice-weekly HD were studied during 240 dialysis sessions. All patients were dialyzed with a nominal total calcium concentration of 1.50 mmol/L. The main assumption of the model is that the calcium distribution volume is equal to the extracellular volume during dialysis. This hypothesis is assumed valid if measured and predicted end dialysis plasma water ionized calcium concentrations are equal. A difference between predicted and measured end-dialysis ionized plasma water calcium concentration is a deviation on our main hypothesis, meaning that a substantial amount of calcium is exchanged between the extracellular volume and a nonmodeled compartment. FINDINGS The difference between predicted and measured values was 0.02 mmol/L (range -0.08:0.16 mmol/L). With a mean ionized dialysate calcium concentration of 1.25 mmol/L, calcium mass balance was on average negative (mean ± SD -0.84 ± 1.33 mmol, range -5.42:2.75). Predialysis ionized plasma water concentration and total ultrafiltrate were the most important predictors of calcium mass balance. A significant mobilization of calcium from the extracellular pool to a nonmodeled pool was calculated in a group of patients. DISCUSSION The proposed single pool variable-volume Calcium kinetic model is adequate for prediction and quantification of intradialysis calcium mass balance, it can evaluate the eventual calcium transfer outside the extracellular pool in clinical practice.
Collapse
Affiliation(s)
| | - Fabio Carfagna
- Depatments of Nephrology and Dialysis, A. Manzoni Hospital, Lecco, Italy
| | - Vincenzo la Milia
- Depatments of Nephrology and Dialysis, A. Manzoni Hospital, Lecco, Italy
| | - Antonio Bellasi
- Depatments of Nephrology and Dialysis, Sant'Anna Hospital, Como, Italy
| | - Giustina Casagrande
- Depatments of Chemistry, Material and Chemical Engineering, Politecnico di Milano, Milano, Italy
| | - Camilla Bianchi
- Depatments of Chemistry, Material and Chemical Engineering, Politecnico di Milano, Milano, Italy
| | - Domenico Vito
- Depatments of Chemistry, Material and Chemical Engineering, Politecnico di Milano, Milano, Italy
| | - Maria Laura Costantino
- Depatments of Chemistry, Material and Chemical Engineering, Politecnico di Milano, Milano, Italy
| | - Giuseppe Rombolà
- Depatments of Nephrology and Dialysis, Hospital and Macchi Foundation, Varese, Italy
| | - Claudio Minoretti
- Depatments of Nephrology and Dialysis, Sant'Anna Hospital, Como, Italy
| | - Carlo Schönholzer
- Depatments of Nephrology and Dialysis, Regional Hospital of Lugano, Lugano, Switzerland
| | | | | |
Collapse
|
5
|
Ionic Dialysance and Determination of Kt/V in on-line Hemodiafiltration with Simultaneous Pre- and Post-dilution. Int J Artif Organs 2013; 36:327-34. [DOI: 10.5301/ijao.5000196] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2012] [Indexed: 11/20/2022]
Abstract
Purpose A direct determination of Kt/V using ionic dialysance for estimating K and bio-impedancemetry for estimating V is compared with the usual indirect estimation based on the second generation Daugirdas equation during a new technique of hemodiafiltration with simultaneous pre- and postdilution (mixed-HDF). Methods In 31 informed consented patients, the urea distribution volume (V) is estimated by total body water (VBCM) measured by the Body Composition Monitor (BCM; Fresenius Medical Care, Bad Homburg, Germany) based on bio-impedance spectroscopy. The value (KOCM t)/VBCM is calculated during 114 mixed-HDF sessions (duration 4 hours) from the measurement of ionic dialysance KOCM by the OCM module, standard on the 5008 dialysis monitor (Fresenius Medical Care, Germany). The single pool (Kt/V)sp is determined from blood urea concentration measurements using the Daugirdas equation. Results Mixed-HDF is a very high-efficiency hemodialysis with a delivered dialysis dose Kt/V near from 2 per 4-hour session. (KOCM t)/VBCM (1.97 ± 0.28) is consistent with (Kt/V)sp (2.01 ± 0.34) with a correlation coefficient at 0.72. Conclusions Direct calculation of Kt/V from estimating K by OCM and V by BCM is consistent with the usual indirect estimation by the second generation Daugirdas equation. Therefore, the regular determination of V by BCM allows the estimation of single-pool Kt/V at each session without the need of blood sampling.
Collapse
|
6
|
Marsenic O, Booker K, Studnicka K, Wilson D, Beck A, Swanson T, Henry D, Turman M. Use of ionic dialysance to calculate Kt/V in pediatric hemodialysis. Hemodial Int 2011; 15 Suppl 1:S2-8. [DOI: 10.1111/j.1542-4758.2011.00595.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Olivera Marsenic
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Kristi Booker
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Kathleen Studnicka
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Donna Wilson
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Ann Beck
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Tiffany Swanson
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Dwayne Henry
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| | - Martin Turman
- Pediatric Nephrology; Oklahoma University Health Sciences Center; Oklahoma City; Oklahoma; USA
| |
Collapse
|
7
|
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.
Collapse
|
8
|
Koubaa A, Potier J, de Préneuf H, Queffelou G, Garcia F, Petitclerc T. Estimation du volume de distribution de l’urée chez le patient hémodialysé. Nephrol Ther 2010; 6:532-6. [DOI: 10.1016/j.nephro.2010.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 04/28/2010] [Accepted: 04/28/2010] [Indexed: 11/27/2022]
|
9
|
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.
Collapse
Affiliation(s)
- Michael J Flanigan
- Nephrology Division, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
| |
Collapse
|
10
|
Di Filippo S, Andrulli S, Mangano S, Baragetti I, Masa A, Di Filippo G, Mura C, Nachtigal J, Baruffaldi M, Barbisoni F, Cravero R, Agliata S, Amar K, Faranna P, Locatelli F. Reduction in urea distribution volume over time in clinically stable dialysis patients. Kidney Int 2006; 69:754-9. [PMID: 16518331 DOI: 10.1038/sj.ki.5000149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have previously shown that, assuming urea distribution volume (V) remains constant for 1 month, ionic dialysance (ID) allows the dialysis dose to be calculated without the need for blood sampling. The aim of this multicenter study was to verify whether the assumption of a constant V can be extended to 1 year. In clinically stable patients receiving thrice-weekly hemodialysis at 13 dialysis centers, V and Kt/V were assessed during three dialysis sessions at baseline and 1 year later using ID as dialyzer urea clearance and the single-pool urea kinetic model. Baseline albumin, hemoglobin, and C reactive protein were prespecified covariates for predicting the change in V over time. Of the 52 enrolled patients, 40 (25 males; age 63.0+/-13.5 years) completed the study. Baseline end-dialysis body weight (62.4+/-13.7 kg) showed a non-significant 1% reduction during follow-up (-0.6+/-2.8 kg; P=0.175), whereas V significantly decreased from 29.0+/-6.8 to 27.4+/-6.0 l (-1.6+/-3.0 l or 4.5%; P=0.002). The reduction in V was greater when baseline albumin was lower (P=0.001) and baseline V was higher (P=0.005). The single-pool K(t)/V calculated using baseline V underestimated the actual value by 0.07+/-0.16 (P=0.008). The slight underestimate of Kt/V during follow-up suggests that annual V evaluations may be sufficient for dialysis dose quantification as the only risk is underestimating the actually delivered dialysis dose. However, the relationship between baseline albumin and the reduction in V over time may have nutritional value, and suggests more frequent V evaluations.
Collapse
Affiliation(s)
- S Di Filippo
- Department of Nephrology and Dialysis, Ospedale A. Manzoni, Lecco, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
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.
Collapse
Affiliation(s)
- Lucile Mercadal
- Department of Nephrology, Pitié-Salpétrière Hospital, Paris, France.
| | | | | |
Collapse
|