Methods for dose quantification in continuous renal replacement therapy: Toward a more precise approach.

Periodic dose assessment is quintessential for dynamic dose adjustment and quality control of continuous renal replacement therapy (CRRT) in critically ill patients with acute kidney injury (AKI). The flows-based methods to estimate dose are easy and reproducible methods to quantify (estimate) CRRT dose at the bedside. In particular, quantification of effluent flow and, mainly, the current dose (adjusted for dialysate, replacement, blood flows, and net ultrafiltration) is routinely used in clinical practice. Unfortunately, these methods are critically influenced by several external unpredictable factors; the estimated dose often overestimates the real biological delivered dose quantified through the measurement of urea clearance (the current effective delivered dose). Although the current effective delivered dose is undoubtedly more precise than the flows-based dose estimation in quantifying CRRT efficacy, some limitations are reported for the urea-based measurement of dose. This article aims to describe the standard of practice for dose quantification in critically ill patients with AKI undergoing CRRT in the intensive care unit. Pitfalls of current methods will be underlined, along with solutions potentially applicable to obtain more precise results in terms of (a) adequate marker solutes that should be used in accordance with the clinical scenario, (b) correct sampling procedures depending on the chosen indicator of transmembrane removal, (c) formulas for calculations, and (d) quality controls and benchmark indicators.

Alkali delivery in chronic hemodialysis: Would more acetate be helpful?

The dialysate alkali used in hemodialysis to replace low body alkali levels in end stage renal disease (ESRD) patients has changed over time from bicarbonate to acetate and finally back to bicarbonate with a small addition of acetate. The ideal way to replace alkali in dialysis patients remains uncertain. Elsewhere in this issue of the journal, Sargent and Gennari, who have contributed greatly to our understanding of dialysis and acid-base kinetics, suggest that decreasing the currently used concentration of bicarbonate while increasing concentration of acetate in the dialysate may be a much more physiological approach to alkali delivery during hemodialysis. These recommendations are based on results from a series of hemodialysis simulations using mathematical theoretical methods, with the assumption that acetate metabolism will be sufficiently delayed with the higher acetate dialysate and reduce the rate of correction of metabolic acidosis during dialysis. Although valuable in calling attention to the issues surrounding alkali repletion during hemodialysis, these postulations should be tested in clinical trials. We believe, however, that the available evidence suggests that the rate of gain of bicarbonate during dialysis with the higher acetate dialysate would not be slower and that the replacement of some dialysate bicarbonate with acetate will not alter alkali accretion or intradialytic pH.

Effect of Dialysate Glucose Concentration on Hepcidin Clearance in Maintenance Hemodialysis Patients.

INTRODUCTION: Hepcidin is a key regulator of iron homeostasis, takes part in pathophysiology of anemia and cardiovascular disease in maintenance hemodialysis (MHD) patients. The aim of this study was to compare the effect of glucose-free and glucose-containing dialysate on the clearance of hepcidin-25 during a hemodialysis (HD) session and discuss its potential mechanism in MHD patients. METHODS: In a longitudinal interventional study of 30 stable MHD patients without diabetes, we measured serum hepcidin-25 and plasma catecholamines (adrenaline, noradrenaline, and dopamine) during HD session using glucose-free dialysate and then switched to 5.55 mmol/L glucose-containing dialysate. One-way analysis of variance (ANOVA) was used to identify the effect of two dialysates on the intra-dialysis changes of hepcidin-25 and catecholamines. Spearman and Pearson correlation coefficients were performed to detect the relationships between hepcidin-25 and catecholamines. RESULTS: Glucose-free dialysate achieved a greater reduction of hepcidin-25 than 5.55 mmol/L glucose-containing dialysate in a single bicarbonate HD session [-8.43 (-15.44 to -1.42) vs. 0.46 (-6.09 to 7.00) %, P < .05]. The intra-dialysis changes of catecholamines showed no significant differences between the two dialysates. The serum hepcidin-25 levels were positively associated with plasma catecholamines levels at pre-, intra- and post-HD (R = 0.22~0.62 with P < .05). CONCLUSIONS: Our findings suggest that glucose-containing dialysate might up-regulate hepcidin-25 synthesis through activation of the sympathetic nervous system or oxidative stress, possibly mediated by increased production of catecholamines. Adequately designed studies are needed to confirm and reveal the mechanisms of dialysate glucose concentration on hepcidin-25 kinetics during HD sessions.

A strategy to reduce inflammation and anemia treatment's related costs in dialysis patients.

This is a post-hoc analysis evaluating erythropoiesis stimulating agents' (ESA) related costs while using an additional ultrafilter (Estorclean PLUS) to produce ultrapure dialysis water located within the fluid pathway after the treatment with reverse osmosis and before the dialysis machine. Twenty-nine patients (19 treated with epoetin alfa and 10 with darboepoetin alfa) were included in the analysis. We showed to gain savings of 210 € per patient (35 € per patient each month) with epoetin alfa during the experimental period of 6 months, compared to the control period and of 545 € per patient (90 € per patient each month) with darboepoetin alfa. Estorclean PLUS had a cost of 600 € (25 € per month per each patient) and was used for 6 months. Intravenous iron therapy with sodium ferrigluconate had a cost of 0,545 €/62,5 mg. In conclusion, during the experimental period with the use of Estorclean, we obtained global savings of 11 € per patient per month with epoetin alfa and 30 € per patient per month with darboepoetin alfa to treat anemia in dialysis patients.

Three-Stream, Bicarbonate-Based Hemodialysis Solution Delivery System Revisited: With an Emphasis on Some Aspects of Acid-Base Principles.

Hemodialysis patients can acquire buffer base (i.e., bicarbonate and buffer base equivalents of certain organic anions) from the acid and base concentrates of a three-stream, dual-concentrate, bicarbonate-based, dialysis solution delivery machine. The differences between dialysis fluid concentrate systems containing acetic acid versus sodium diacetate in the amount of potential buffering power were reviewed. Any organic anion such as acetate, citrate, or lactate (unless when combined with hydrogen) delivered to the body has the potential of being converted to bicarbonate. The prescribing physician aware of the role that organic anions in the concentrates can play in providing buffering power to the final dialysis fluid, will have a better knowledge of the amount of bicarbonate and bicarbonate precursors delivered to the patient.

Comparison of intradialytic hemodynamic tolerance between on-line hemodiafiltration and acetate-free biofiltration with profiled potassium dialysate concentration.

Intradialytic hypotensive episodes are deleterious for hemodialysis (HD) patients. Acetate-free biofiltration with profiled potassium (AFBK) dialysate concentration may improve their cardiovascular stability. The aim of the present crossover study was to compare intradialytic hemodynamic tolerance and biological parameters between online hemodiafiltration (olHDF) and AFBK. Ten frail HD patients (8 males) with a mean age of 66.71- ± 12.31 years were studied for three months on olHDF and AFBK. There was a significant reduction of the hypotensive episodes during the AFBK period compared to the olHDF period. Mean intradialytic systolic and diastolic blood pressures were significantly higher during the AFBK period. There was a significant postdialytic increase in serum sodium concentration with the AFBK compared to olHDF. The dry weight and ultrafiltration indices were significantly higher, and the Kt/V was significantly lower during the AFBK period. Serum albumin concentration significantly increased during the AFBK period. AFBK leads to a significantly improved intradialytic tolerance in hemodynamically instable HD patients.

A randomized cross-over study comparing the performance of HD integra™ central concentrate system versus pre-produced concentrate in hemodialysis.

BACKGROUND: Pre-produced bicarbonate concentrates (PPC) are still widely used in developing countries despite its cost and risk but Central Concentrate System (CCS) is lacking in data to support its wider adoption. METHODS: We conducted an 8-week randomized crossover study on 16 Hemodialysis machines to compare CCS versus PPC. Performance is assessed by solute concentrations while safety is assessed by microbial count, endotoxin level and adverse event reporting. RESULTS: Microbial counts and endotoxin levels were monitored on 48 occasions during the 8-week study for the CCS arm of the study. The levels were all below the action limit during the study. No patient reported any adverse events. Dialysate Sodium, Chloride and Bicarbonate concentrations were measured on a total of 128 occasions for each arm of the study. The relative deviations of Sodium, Chloride and Bicarbonate concentration were within ±5% of their nominal values for both. The 95% Confidence Intervals for the ratio of the mean solute concentrations on the CCS to PPC lie within the tolerance limit of ±5%. CONCLUSION: Modern CCS is bacteriologically safe and its performance statistically equivalent to PPC.

Estudio de la eficacia de sellado en el periodo interdialítico largo para catéteres de hemodiálisis disfuncionantes / Study of sealing efficiency in the long interdialytic period for dysfunctioning hemodialysis catheters

El sellado de los catéteres venosos tunelizados con distintas soluciones se ha utilizado tanto en la prevención como en el tratamiento de complicaciones, sin embargo, no existe la solución ideal. El objetivo del estudio es comparar las complicaciones de de los catéteres disfuncionantes con diferentes pautas de sellado de fin de semana, Urokinasa 10.000 UI vs TauroLock(TM)-U25.000, así como eficacia dialítica de los mismos. Se trata de un estudio observacional longitudinal de cohorte en el que se analizan los casos de infección, trombosis y funcionalidad del catéter tunelizado. Se incluyen sólo los pacientes con catéter disfuncionante que tenían previamente prescrita una pauta de sellado con urokinasa en el periodo interdialítico largo. El periodo de estudio fue de cuatro meses; dos con sellado con 10.000 UI de Urokinasa y dos con sellado de TauroLock(TM)-U25.000. Las medias de Urokinasa vs Taurolidina: flujo sanguíneo, PV, recirculación, KT (53.3/55L), manipulación y dosis extra de urokinasa fueron mejor en el periodo de Taurolock, aunque no se encontraron diferencias estadísticamente significativas. La media de PA es cercana a la significación (p=0.067) mejor también en el periodo de Taurolock. Hubo una diferencia en la media de KT favorable al periodo de Taurolock que no tiene significación estadística y es exclusivo de los pacientes que no necesitaron urokinasa extra. La principal limitación de nuestro estudio es el tamaño muestral que puede ser el responsable en parte, de la ausencia de significación estadística. Son necesarios estudios con mayor número de pacientes (AU)

The sealing of the tunneled venous catheters with different solutions has been used both in prevention and in the treatment of complications, however, there is no ideal solution. The aim of the study is to compare the complications of dysfunctional catheters with different weekend sealing patterns, Urokinase 10,000 IU vs TauroLock(TM) -U25,000, as well as dialytic efficacy of both substances. A longitudinal observational cohort study in which the cases of infection, thrombosis and functionality of the tunneled catheter were analyzed. Only patients with a dysfunctioning catheter who had previously prescribed a sealing pattern with urokinase in the long interdialytic period were included. The study period was four months; two months sealed with 10,000 IU of Urokinase and the other ones, sealed with TauroLock (TM) -U25,000. Urokinase vs Taurolidine averages: blood flow, venous pressure, recirculation, KT (53.3 / 55L), manipulation and extra doses of urokinase were better in the Taurolock period, although no statistically significant differences were found. The mean arterial pressure is close to the significance (p = 0.067), also better in the Taurolock period. There was a difference in the KT mean, favorable to the Taurolock period, which has no statistical significance and is exclusive to patients who did not require extra urokinase. The main limitation of our study is the sample size that may be partly responsible for the absence of statistical significance. Studies with more patients are necessary (AU)

Electrolytes-Enriched Hemodiafiltration Solutions for Continuous Renal Replacement Therapy in Acute Kidney Injury: A Crossover Study.

AIMS: To evaluate the capability of an electrolytes-enriched solution to prevent metabolic disorders during continuous veno-venous hemodiafiltration (CVVHDF). METHODS: Serum biochemistry and clinical tolerance were compared during CVVHDF treatments with an electrolyte-enriched (Phoxilium) or standard solutions in 10 acute renal failure patients. RESULTS: As compared to standard fluids, serum potassium and phosphate levels were maintained in the normal range with Phoxilium without any supplementation but total serum calcium levels were significantly lower. Bicarbonatemia was slightly higher (24-26 vs. 21.5-24.5 mmol/l, p < 0.05) with conventional solutions and was associated with a significant increased level of pH (>7.44). Despite the absence of glucose in the Phoxilium solution, blood glucose levels and glucose supplementation were similar between treatments. Clinical tolerance and efficiency of CVVHDF sessions were comparable. CONCLUSION: Phoxilium effectively prevented hypophosphatemia and hypokalemia during CVVHDF. It was, however, associated with a slight metabolic acidosis and hypocalcemia compared with conventional solutions.

Evaluación de la efectividad y satisfacción del apósito con Gluconato de Clorhexidina 3M(TM) Tegaderm(TM) en el cuidado del catéter central tunelizado para hemodiálisis / Evaluation of the effectiveness and safety of 3M(TM) Tegaderm(TM) chlorhexidine gluconate dressing in the care of the central vascular catheter tunneled for hemodialysis

Introducción: Son múltiples los métodos y materiales utilizados para el manejo del orificio de inserción del catéter venoso central tunelizado para hemodiálisis con el fin de prevenir infecciones asociadas a su uso. El objetivo de este estudio es analizar el uso del Apósito con Gluconato de Clorhexidina 3M™ Tegaderm™ con respeto al Apósito formado por gasa y esparadrapo en la cura del orificio de inserción del catéter tunelizado para hemodiálisis. Material y método: Se ha llevado a cabo un estudio prospectivo durante 32 semanas en el que se han incluido 9 pacientes portadores de catéter venoso central tunelizado. Se han recogido datos referentes al estado del orificio de inserción del catéter, del túnel, de la zonza colindante, aplicabilidad del material, satisfacción del paciente, percepción del profesional y costes. Resultados: No se ha evidenciado diferencias en la eficacia para la prevención de infecciones entre ambos apósitos. En el análisis de satisfacción, se constata una mayor percepción de seguridad con el uso del apósito con clorhexidina además de una reducción de coste de la técnica. Discusión: Basándonos en los costes, satisfacción del paciente y en la percepción del personal de enfermería responsable de la técnica, el Apósito con Gluconato de Clorhexidina es una buena alternativa para el cuidado del orificio de inserción del catéter tunelizado para hemodiálisis (AU)

Introduction: There are multiple methods and materials used for handling the insertion hole of the central venous catheter tunneled for hemodialysis, in order to prevent infection associated with their use. The aim of this study is to analyze the use of 3M™ Tegaderm™ CHG dressing with respect to the dressing formed by gauze and tape in the cure of insertion hole of the tunneled hemodialysis catheter. Material and methods: A prospective study for 32 weeks was conducted, in which 9 patients with central venous catheter tunneled were included. Data on the state of: catheter insertion hole, tunnel, neighboring area, applicability of the material, patient satisfaction, perception of professional and costs were collected Results: No significant difference in efficacy for the prevention of infections between the two dressings was found. In the analysis of satisfaction a greater perception of safety with the use of the dressing with chlorhexidine was observed as well as a reduction of cost of the technique. Discussion: Based on cost, patient satisfaction and perception of the nursing staff responsible for the technique, the dressing with chlorhexidine gluconate is a good alternative for the cure of insertion hole of the tunneled hemodialysis catheter (AU)

The Effect of Increased Frequency of Hemodialysis on Volume-Related Outcomes: A Secondary Analysis of the Frequent Hemodialysis Network Trials.

In previous reports of the Frequent Hemodialysis Network trials, frequent hemodialysis (HD) reduced extracellular fluid (ECF) and left ventricular mass (LVM), with more pronounced effects observed among patients with low urine volume (UVol). We analyzed the effect of frequent HD on interdialytic weight gain (IDWG) and a time-integrated estimate of ECF load (TIFL). We also explored whether volume and sodium loading contributed to the change in LVM over the study period. Treatment effects on volume parameters were analyzed for modification by UVol and the dialysate-to-serum sodium gradient. Predictors of change in LVM were determined using linear regression. Frequent HD reduced IDWG and TIFL in the Daily Trial. Among patients with UVol <100 ml/day, reduction in TIFL was associated with LVM reduction. This suggests that achievement of better volume control could attenuate changes in LVM associated with mortality and cardiovascular morbidity. TIFL may prove more useful than IDWG alone in guiding HD practice. Video Journal Club 'Cappuccino with Claudio Ronco' at http://www.karger.com/?doi=441966.

Low-Sodium Versus Standard-Sodium Peritoneal Dialysis Solution in Hypertensive Patients: A Randomized Controlled Trial.

BACKGROUND: Peritoneal dialysis (PD) solutions with reduced sodium content may have advantages for hypertensive patients; however, they have lower osmolarity and solvent drag, so the achieved Kt/Vurea may be lower. Furthermore, the increased transperitoneal membrane sodium gradient can influence sodium balance with consequences for blood pressure (BP) control. STUDY DESIGN: Prospective, randomized, double-blind clinical trial to prove the noninferiority of total weekly Kt/Vurea with low-sodium versus standard-sodium PD solution, with the lower confidence limit above the clinically accepted difference of -0.5. SETTING & PARTICIPANTS: Hypertensive patients (≥ 1 antihypertensive drug, including diuretics, or office systolic BP ≥ 130 mmHg) on continuous ambulatory PD therapy from 17 sites. INTERVENTION: 108 patients were randomly assigned (1:1) to 6-month treatments with either low-sodium (125 mmol/L of sodium; 1.5%, 2.3%, or 4.25% glucose; osmolarity, 338-491 mOsm/L) or standard-sodium (134 mmol/L of sodium; 1.5%, 2.3%, or 4.25% glucose; osmolarity, 356-509 mOsm/L) PD solution. OUTCOMES: Primary end point: weekly total Kt/Vurea; secondary outcomes: BP control, safety, and tolerability. MEASUREMENTS: Total Kt/Vurea was determined from 24-hour dialysate and urine collection; BP, by office measurement. RESULTS: Total Kt/Vurea after 12 weeks was 2.53 ± 0.89 in the low-sodium group (n = 40) and 2.97 ± 1.58 in the control group (n = 42). The noninferiority of total Kt/Vurea could not be confirmed. There was no difference for peritoneal Kt/Vurea (1.70 ± 0.38 with low sodium, 1.77 ± 0.44 with standard sodium), but there was a difference in renal Kt/Vurea (0.83 ± 0.80 with low sodium, 1.20 ± 1.54 with standard sodium). Mean daily sodium removal with dialysate at week 12 was 1.188 g higher in the low-sodium group (P < 0.001). BP changed marginally with standard-sodium solution, but decreased with low-sodium PD solution, resulting in less antihypertensive medication. LIMITATIONS: Broader variability of study population than anticipated, particularly regarding residual kidney function. CONCLUSIONS: The noninferiority of the low-sodium PD solution for total Kt/Vurea could not be proved; however, it showed beneficial clinical effects on sodium removal and BP.

Isonatric Dialysis Biofeedback in Hemodiafiltration with Online Regeneration of Ultrafiltrate in Hypertensive Hemodialysis Patients: A Randomized Controlled Study.

UNLABELLED: Dialysis biofeedback in hemodiafiltration with online regeneration of ultrafiltrate (HFR) could help to improve arterial hypertension. We evaluated the impact of isonatric HFR (HFR-iso) on hypertension control compared to conventional HFR. Forty-seven hemodialysis patients were included and randomized (ratio 2/1) HFR-iso versus HFR during 24 dialysis sessions. In the HFR-iso group (32 patients, 768 dialysis sessions), the predialytic systolic blood pressure (BP) decreased from S1 to S24 of 9 ± 20 mm Hg and increased of 5 ± 24 mm Hg in the HFR group (15 patients, 360 dialysis sessions), variation that differed between the 2 groups (x0394;S1-S24, p = 0.035; interaction group*time, p = 0.012). The diastolic BP (HFR-iso -3 ± 14 mm Hg vs. HFR 5 ± 13 mm Hg; p = 0.088), the DDD of antihypertensive treatment and the dry weight did not vary significantly during the study. Number of sessions complicated by symptomatic hypotension was similar in the 2 groups. HFR-iso improved BP control without increasing dialysis hypotension episodes. SHORT SUMMARY: In this multicenter, open-label, controlled, randomized study, we evaluated the impact of dialysis biofeedback in HFR on arterial hypertension compared to conventional HFR. We observed that HFR-iso improved arterial BP control without increasing dialysis hypotension episodes.

Effect of Lowering the Dialysate Temperature in Chronic Hemodialysis: A Systematic Review and Meta-Analysis.

BACKGROUND AND OBJECTIVES: Lowering the dialysate temperature may improve outcomes for patients undergoing chronic hemodialysis. We reviewed the reported benefits and harms of lower temperature dialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We searched the Cochrane Central Register, OVID MEDLINE, EMBASE, and Pubmed until April 15, 2015. We reviewed the reference lists of relevant reviews, registered trials, and relevant conference proceedings. We included all randomized, controlled trials that evaluated the effect of reduced temperature dialysis versus standard temperature dialysis in adult patients receiving chronic hemodialysis. We followed the Grading of Recommendations Assessment, Development and Evaluation approach to assess confidence in the estimates of effect (i.e., the quality of evidence). We conducted meta-analyses using random effects models. RESULTS: Twenty-six trials were included, consisting of a total of 484 patients. Compared with standard temperature dialysis, reduced temperature dialysis significantly reduced the rate of intradialytic hypotension by 70% (95% confidence interval, 49% to 89%) and significantly increased intradialytic mean arterial pressure by 12 mmHg (95% confidence interval, 8 to 16 mmHg). Symptoms of discomfort occurred 2.95 (95% confidence interval, 0.88 to 9.82) times more often with reduced temperature compared with standard temperature dialysis. The effect on dialysis adequacy was not significantly different, with a Kt/V mean difference of -0.05 (95% confidence interval, -0.09 to 0.01). Small sample sizes, loss to follow-up, and a lack of appropriate blinding in some trials reduced confidence in the estimates of effect. None of the trials reported long-term outcomes. CONCLUSIONS: In patients receiving chronic hemodialysis, reduced temperature dialysis may reduce the rate of intradialytic hypotension and increase intradialytic mean arterial pressure. High-quality, large, multicenter, randomized trials are needed to determine whether reduced temperature dialysis affects patient mortality and major adverse cardiovascular events.

Utilidad de las tiras reactivas multistix 10 SG(R) en el diagnóstico de peritonitis en diálisis peritoneal / Utility of the Multistix 10 SG (R) reagent strips in the diagnosis of peritonitis in peritoneal dialysis

Introducción: La infección peritoneal es una complicación frecuente en diálisis peritoneal, que condiciona una importante morbimortalidad. Habitualmente el diagnóstico se establece mediante signos y síntomas clínicos, efluente turbio y cultivo positivo. En ocasiones los síntomas son poco evidentes, el recuento leucocitario puede no estar disponible y el cultivo se demora varios días. Por otro lado se sabe que el inicio precoz del tratamiento antibiótico aumenta la eficacia y favorece la resolución de los episodios de infección peritoneal. Objetivo: Estudiar la capacidad diagnóstica de las tiras reactivas Multistix 10 SG Siemens® en la determinación de peritonitis en pacientes en diálisis peritoneal. Material y métodos: Estudio observacional prospectivo donde se analizaron muestras de líquido peritoneal efluente de pacientes prevalentes en diálisis peritoneal, durante seis meses. Se tomó como criterio de peritonitis la presencia de más de 100 Leucocitos (L)/ μl y más de 50% de ellos polimorfonucleares. Las muestras de líquido peritoneal efluente fueron obtenidas después de permanencias mínimas de dos horas y volumen mínimo de 1500 cc. Todas las muestras se analizaron usando tiras reactivas de Multistix ® 10 SG Siemens durante 2 minutos, anotando el observador el resultado de acuerdo a la escala cromática (valor 0= 0-15 L/μl, valor 1= 16-70 L/μl, valor 2=71-125 L/μl y valor 3=126-500 L/μl) y se compararon con las enviadas al laboratorio de nuestro hospital para el recuento manual de leucocitos. Se recogieron otras variables clínicas y epidemiológicas. Resultados: Se analizaron 111 muestras de efluente peritoneal. Detectándose infección peritoneal en 28 muestras (25.2%). No se observaron diferencias significativas entre infectados y no infectados por razón de edad, sexo, diabetes ni número de peritonitis anteriores. El 68 % de los pacientes infectados declararon sufrir dolor. El 73% de las muestras con infección presentaron líquido turbio. En relación al resultado del Multistix, y considerando infección un valor por encima de 1, encontramos una sensibilidad del 100% y una especificidad del 95.2%. Si el punto de corte se toma en el valor 2 encontramos una sensibilidad del 96,4% y una especificidad del 100%. Conclusiones: La utilización de las tiras Multistix® 10 SG Siemens como prueba diagnóstica para la detección de infección peritoneal, tiene una validez excelente, pudiendo sustituir al recuento manual de leucocitos (AU)

Introduction: Peritoneal infection is a common com- plication in peritoneal dialysis, which determined a significant morbidity and mortality. Usually the diagnosis is established by clinical signs and symptoms, cloudy effluent and positive culture. Sometimes the symptoms are not evident, the leukocyte count may not be available and culture takes several days. On the other hand it is known that early antibiotic therapy increases effectiveness and promotes the resolution of the episodes of peritoneal infection. Objective: Study the diagnostic capacity of Siemens Multistix 10 SG® reagent strips in determining peritonitis in patients on peritoneal dialysis. Methods: A prospective observational study was carried out. Samples of peritoneal fluid effluent from prevalent patients on peritoneal dialysis were analyzed for six months. It was taken as the criterion of peritonitis, the presence of more than 100 leukocytes (L)/ μl and over 50% of these polymorphs. Samples of peritoneal fluid effluent were obtained after two-hours minimum stays and minimum volume of 1500 cc. All samples were analyzed using Siemens Multistix 10 SG® reagent strips for 2 minutes, scoring the observer the result according to the chromatic scale (value 0 = 0-15 L / μl; value 1 = 16-70 L / μl; value 2 = 71-125 L / μl; and value 3 = 126-500 L / μl) and compared to those sent to the hospital laboratory for manual leukocyte count. Other clinical and epidemiological variables were collected. Results: 111 samples of peritoneal dialysis were analyzed. Peritoneal infection were detected in 28 samples (25.2%). No significant differences between infected and uninfected by reason of age, sex, diabetes or number of previous peritonitis were observed. 68% of infected patients reported suffering from pain. In those infected samples, 73% presented cloudy fluid. In relation to the result of Multistix and considering infection a value greater than 1, we found a sensitivity of 100% and a specificity of 95.2%. If the cut point is taken in the value 2 we found a sensitivity of 96.4% and a specificity of 100%. Conclusions: The use Siemens Multistix 10 SG® reagent strips as a diagnostic test for the detection of peritoneal infection has excellent validity and could replace the manual leukocyte count (AU)

Randomized Controlled Trial of Individualized Dialysate Cooling for Cardiac Protection in Hemodialysis Patients.

BACKGROUND AND OBJECTIVES: Cardiovascular disease is the most common cause of death in patients on hemodialysis (HD). HD-associated cardiomyopathy is appreciated to be driven by exposure to recurrent and cumulative ischemic insults resulting from hemodynamic instability of conventionally performed intermittent HD treatment itself. Cooled dialysate reduces HD-induced recurrent ischemic injury, but whether this confers long-term protection of the heart in terms of cardiac structure and function is not known. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Between September 2009 and January 2013, 73 incident HD patients were randomly assigned to a dialysate temperature of 37°C (control) or individualized cooling at 0.5°C below body temperature (intervention) for 12 months. Cardiac structure, function, and aortic distensibility were assessed by cardiac magnetic resonance imaging. Mean between-group difference in delivered dialysate temperature was 1.2°C±0.3°C. Treatment effects were determined by the interaction of treatment group with time in linear mixed models. RESULTS: There was no between-group difference in the primary outcome of left ventricular ejection fraction (1.5%; 95% confidence interval, -4.3% to 7.3%). However, left ventricular function assessed by peak systolic strain was preserved by the intervention (-3.3%; 95% confidence interval, -6.5% to -0.2%) as was diastolic function (measured as peak diastolic strain rate, 0.18 s(-1); 95% confidence interval, 0.02 to 0.34 s(-1)). Reduction of left ventricular dilation was demonstrated by significant reduction in left ventricular end-diastolic volume (-23.8 ml; 95% confidence interval, -44.7 to -2.9 ml). The intervention was associated with reduced left ventricular mass (-15.6 g; 95% confidence interval, -29.4 to -1.9 g). Aortic distensibility was preserved in the intervention group (1.8 mmHg(-1)×10(-3); 95% confidence interval, 0.1 to 3.6 mmHg(-1)×10(-3)). There were no intervention-related withdrawals or adverse events. CONCLUSIONS: In patients new to HD, individualized cooled dialysate did not alter the primary outcome but was well tolerated and slowed the progression of HD-associated cardiomyopathy. Because cooler dialysate is universally applicable at no cost, the intervention warrants wider adoption or confirmation of these findings in a larger trial.

Low dialysate potassium and central arterial pressure waveform.

BACKGROUND: Cardiovascular mortality is high in hemodialysis (HD) patients. Early arterial pressure wave reflections predict mortality in HD patients, and HD acutely improves the central pressure waveform. Potassium (K) plays a crucial role in cardiac electrophysiology, and patients with end-stage kidney disease depend on HD for neutral K balance. We aimed to study the impact of dialysate K concentrations on central arterial pressure waveform. METHODS: Thirty-three chronic HD patients were studied before and after a HD session, and the prescribed dialysate K concentration was recorded. In a subset of 23 patients without arrhythmias, pulse wave analysis was performed on radial arteries. Nine patients had dialysate K set to 1 mmol/L (group 1), and 14 patients had K set to 2 or 3 mmol/L (group 2). Augmentation index (AIx), defined as difference between the second and first systolic peak divided by central pulse pressure, was used as a measure of arterial stiffness. RESULTS: HD reduced the AIx in group 1 only (p = 0.0005). Likewise, central systolic pressure was reduced in group 1 only (p = 0.006). The relative reduction of AIx post-HD was significantly higher in group 1 compared with group 2 (p < 0.0001). The association between low dialysate K and AIx reduction remained statistically significant after adjustment for variables including the change in central and peripheral systolic pressure and mean arterial pressure. CONCLUSION: Low dialysate K is strongly and independently associated with the acute improvement of AIx.