Is central venous catheter in haemodialysis still the main factor of mortality after hospitalization?

BACKGROUND: Haemodialysis is the most frequently prescribed Renal Replacement Therapy modality worldwide. However, patients undergoing this therapy have an unpredictable evolution related to vascular access. OBJECTIVE: To determine the factors associated with the mortality and hospitalization rate in haemodialysis patients at a third-level care Centre in the Dominican Republic. METHODS: This was an observational and prospective study involving a cohort of 192 haemodialysis patients. The patient selection was non-probabilistic for convenience, and a direct source questionnaire was applied. RESULTS: Of the 192 patients in the cohort, 103 (53.6%) were hospitalized and evaluated. The most frequent cause of hospitalization was catheter-related bloodstream infections (53.4%). Almost one-third (28.2%) of the hospitalized patients died, mostly due to infections (12.6%). Of those who died 29 patients (90%) had a Central venous catheter (CVC) with a non-tunnelled catheter (NTCVC) (65.5%); having an NTC CVC makes a patient 85.5 times more likely to be hospitalized than patients with arteriovenous fistulas. CONCLUSION: Vascular access plays a predominant role in the hospitalization and mortality rates in haemodialysis. Patients with an arteriovenous fistula obtained significantly better outcomes than those with central venous catheters.

How to Improve the Biocompatibility of Peritoneal Dialysis Solutions (without Jeopardizing the Patient's Health).

Peritoneal dialysis (PD) is an important, if underprescribed, modality for the treatment of patients with end-stage kidney disease. Among the barriers to its wider use are the deleterious effects of currently commercially available glucose-based PD solutions on the morphological integrity and function of the peritoneal membrane due to fibrosis. This is primarily driven by hyperglycaemia due to its effects, through multiple cytokine and transcription factor signalling-and their metabolic sequelae-on the synthesis of collagen and other extracellular membrane components. In this review, we outline these interactions and explore how novel PD solution formulations are aimed at utilizing this knowledge to minimise the complications associated with fibrosis, while maintaining adequate rates of ultrafiltration across the peritoneal membrane and preservation of patient urinary volumes. We discuss the development of a new generation of reduced-glucose PD solutions that employ a variety of osmotically active constituents and highlight the biochemical rationale underlying optimization of oxidative metabolism within the peritoneal membrane. They are aimed at achieving optimal clinical outcomes and improving the whole-body metabolic profile of patients, particularly those who are glucose-intolerant, insulin-resistant, or diabetic, and for whom daily exposure to high doses of glucose is contraindicated.

A New Peritoneal Dialysis Solution Containing L-Carnitine and Xylitol for Patients on Continuous Ambulatory Peritoneal Dialysis: First Clinical Experience.

Peritoneal dialysis (PD) is a feasible and effective renal replacement therapy (RRT) thanks to the dialytic properties of the peritoneal membrane (PM). Preservation of PM integrity and transport function is the key to the success of PD therapy, particularly in the long term, since the prolonged exposure to unphysiological hypertonic glucose-based PD solutions in current use is detrimental to the PM, with progressive loss of peritoneal ultrafiltration capacity causing technique failure. Moreover, absorbing too much glucose intraperitoneally from the dialysate may give rise to a number of systemic metabolic effects. Here we report the preliminary results of the first clinical experience based on the use in continuous ambulatory PD (CAPD) patients of novel PD solutions obtained through partly replacing the glucose load with other osmotically active metabolites, such as L-carnitine and xylitol. Ten CAPD patients were treated for four weeks with the new solutions. There was good tolerance to the experimental PD solutions, and no adverse safety signals were observed. Parameters of dialysis efficiency including creatinine clearance and urea Kt/V proved to be stable as well as fluid status, diuresis, and total peritoneal ultrafiltration. The promising tolerance and local/systemic advantages of using L-carnitine and xylitol in the PD solution merit further research.

The osmo-metabolic approach: a novel and tantalizing glucose-sparing strategy in peritoneal dialysis.

Peritoneal dialysis (PD) is a viable but under-prescribed treatment for uremic patients. Concerns about its use include the bio-incompatibility of PD fluids, due to their potential for altering the functional and anatomical integrity of the peritoneal membrane. Many of these effects are thought to be due to the high glucose content of these solutions, with attendant issues of products generated during heat treatment of glucose-containing solutions. Moreover, excessive intraperitoneal absorption of glucose from the dialysate has many potential systemic metabolic effects. This article reviews the efforts to develop alternative PD solutions that obviate some of these side effects, through the replacement of part of their glucose content with other osmolytes which are at least as efficient in removing fluids as glucose, but less impactful on patient metabolism. In particular, we will summarize clinical studies on the use of alternative osmotic ingredients that are commercially available (icodextrin and amino acids) and preclinical studies on alternative solutions under development (taurine, polyglycerol, carnitine and xylitol). In addition to the expected benefit of a glucose-sparing approach, we describe an 'osmo-metabolic' approach in formulating novel PD solutions, in which there is the possibility of exploiting the pharmaco-metabolic properties of some of the osmolytes to attenuate the systemic side effects due to glucose. This approach has the potential to ameliorate pre-existing co-morbidities, including insulin resistance and type-2 diabetes, which have a high prevalence in the dialysis population, including in PD patients.

Acute peritoneal dialysis in the treatment of COVID-19-related acute kidney injury.

The kidney is not typically the main target of severe acute respiratory syndrome coronavirus 2, but surprisingly, acute kidney injury (AKI) may occur in 4-23% of cases, whereas the dialysis management of AKI from coronavirus 2019 has not gained much attention. The severity of the pandemic has resulted in significant shortages in medical supplies, including respirators, ventilators and personal protective equipment. Peritoneal dialysis (PD) remains available and has been used in clinical practice for AKI for >70 years; however, it has been used on only a limited basis and therefore experience and knowledge of its use has gradually vanished, leaving a considerable gap. The turning point came in 2007, with a series of sequential publications providing solid evidence that PD is a viable option. As there was an availability constraint and a capacity limit of equipment/supplies in many countries, hemodialysis and convective therapies became alternatives. However, even these therapies are not available in many countries and their capacity is being pushed to the limit in many cities. Evidence-based PD experience lends support for the use of PD now.

Incident elderly patients on peritoneal dialysis: Epidemiological characteristics and modality impact on survival time.

Aging of the population and the increased prevalence of diseases such as diabetes and arterial hypertension result in an increasing need of dialysis treatment. Herein we describe a cohort of elderly patients on peritoneal dialysis (PD) and assess the influence of the modality on the long-term survival. Out of a multicenter prospective cohort of 2,144 BRAZPD PD incident patients during a period from December 2004 to October 2007, 762 elderly adults, defined as patients ≥65-year-old, were eligible for the study, 413 started on automated PD (APD) and 349 on continuous ambulatory PD (CAPD). Patients were followed until death, transfer to hemodialysis, recovery of renal function, loss to follow-up, or transplantation. Demographics and clinical data were evaluated at baseline and described as mean ± standard deviation, median, or percentage. Competing risk and time-dependent Cox analysis were performed, having dialysis modality APD] vs. CAPD as a dependent variable, as hazard ratio (HR) is not proportional throughout the therapy time. Mean age was 74.5 ± 6.8 years in APD, 74.6 ± 6.7 in CAPD, 50.8% females in APD, 54.4% in CAPD. The frequently observed comorbidities were diabetes (52.3% in APD and 47% in CAPD) and left ventricular hypertrophy (36.3% in APD and 46.1% in CAPD) whereas 93.6% presented Davies score ≥2. In Cox time-dependent analysis, HR did not show difference up to 18 months HR = 1.11, confidence interval (CI) = 0.85-1.46], but thereafter, APD modality revealed lower risk of mortality (HR = 0.25, CI = 0.0073-0.86), when compared with CAPD. After adjustment for the confounding factors, CAPD presented a higher risk of mortality (HR = 4.50, CI = 1.29-15.64). No differences in survival were observed up to 18 months of therapy; however, beyond 18 months, APD modality was a protection factor.

Metformin in peritoneal dialysis: a pilot experience.

OBJECTIVE: In a number of patients, the antidiabetic drug metformin has been associated with lactic acidosis. Despite the fact that diabetes mellitus is the most common cause of end-stage renal disease (ESRD) and that peritoneal dialysis (PD) is an expanding modality of treatment, little is known about optimal treatment strategies in the large group of PD patients with diabetes. In patients with ESRD, the use of metformin has been limited because of the perceived risk of lactic acidosis or severe hypoglycemia. However, metformin use is likely to be beneficial, and PD might itself be a safeguard against the alleged complications. METHODS: Our study involved 35 patients with insulin-dependent type 2 diabetes [median age: 54 years; interquartile range (IQR): 47-59 years] on automated PD (APD) therapy. Patients with additional risk factors for lactic acidosis were excluded. Metformin was introduced at a daily dose in the range 0.5 - 1.0 g. All patients were monitored for glycemic control by blood sugar levels and HbA1c. Plasma lactic acid levels were measured weekly for 4 weeks and then monthly to the end of the study. Plasma and effluent metformin and plasma lactate levels were measured simultaneously. RESULTS: In this cohort, the median duration of diabetes was 18 years (IQR: 14 - 21 years), median time on PD was 31 months (IQR: 27 - 36 months), and median HbA1c was 6.8% (IQR: 5.9% - 6.9%). At metformin introduction and at the end of the study, the median anion gap was 11 mmol/L (IQR: 9 - 16 mmol/L) and 12 mmol/L (IQR: 9 - 16 mmol/L; p > 0.05) respectively, median pH was 7.33 (IQR: 7.32 - 7.36) and 7.34 (IQR: 7.32 - 7.36, p > 0.05) respectively, and mean metformin concentration in plasma and peritoneal fluid was 2.57 ± 1.49 mg/L and 2.83 ± 1.7 mg/L respectively. In the group overall, mean lactate was 1.39 ± 0.61 mmol/L, and hyperlactemia (>2 mmol/L to 5 mmol/L) was found in 4 of 525 plasma samples (0.76%), but the patients presented no symptoms. None of the patients registered a plasma lactate level above 5 mmol/L. We observed no correlation between plasma metformin and plasma lactate (r = 0.27). CONCLUSIONS: Metformin may be used with caution in APD patients with insulin-dependent type 2 diabetes. Although our study demonstrated the feasibility of metformin use in APD, it was not large enough to demonstrate safety; a large-scale study is needed.

Back to basics: pitting edema and the optimization of hypertension treatment in incident peritoneal dialysis patients (BRAZPD).

Systemic arterial hypertension is an important risk factor for cardiovascular disease that is frequently observed in populations with declining renal function. Initiation of renal replacement therapy at least partially decreases signs of fluid overload; however, high blood pressure levels persist in the majority of patients after dialysis initiation. Hypervolemia due to water retention predisposes peritoneal dialysis (PD) patients to hypertension and can clinically manifest in several forms, including peripheral edema. The approaches to detect edema, which include methods such as bioimpedance, inferior vena cava diameter and biomarkers, are not always available to physicians worldwide. For clinical examinations, the presence of pitting located in the lower extremities and/or over the sacrum to diagnose the presence of peripheral edema in their patients are frequently utulized. We evaluated the impact of edema on the control of blood pressure of incident PD patients during the first year of dialysis treatment. Patients were recruited from 114 Brazilian dialysis centers that were participating in the BRAZPD study for a total of 1089 incident patients. Peripheral edema was diagnosed by the presence of pitting after finger pressure was applied to the edematous area. Patients were divided into 2 groups: those with and without edema according to the monthly medical evaluation. Blood arterial pressure, body mass index, the number of antihypertensive drugs and comorbidities were analyzed. We observed an initial BP reduction in the first five months and a stabilization of blood pressure levels from five to twelve months. The edematous group exhibited higher blood pressure levels than the group without edema during the follow-up. The results strongly indicate that the presence of a simple and easily detectable clinical sign of peripheral edema is a very relevant tool that could be used to re-evaluate not only the patient's clinical hypertensive status but also the PD prescription and patient compliance.

Geographic and educational factors and risk of the first peritonitis episode in Brazilian Peritoneal Dialysis study (BRAZPD) patients.

BACKGROUND AND OBJECTIVES: Peritonitis remains as the most frequent cause of peritoneal dialysis (PD) failure, impairing patient's outcome. No large multicenter study has addressed socioeconomic, educational, and geographic issues as peritonitis risk factors in countries with a large geographic area and diverse socioeconomic conditions, such as Brazil. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Incident PD patients recruited from 114 dialysis centers and reporting to BRAZPD, a multicenter observational study, from December 2004 through October 2007 were included. Clinical, dialysis-related, demographic, and socioeconomic variables were analyzed. Patients were followed up until their first peritonitis. Cox proportional model was used to determine independent factors associated with peritonitis. RESULTS: In a cumulative follow-up of 2032 patients during 22.026 patient-months, 474 (23.3%) presented a first peritonitis episode. In contrast to earlier findings, PD modality, previous hemodialysis, diabetes, gender, age, and family income were not risk predictors. Factors independently associated with increased hazard risk were lower educational level, non-white race, region where patients live, shorter distance from dialysis center, and lower number of patients per center. CONCLUSIONS: Educational level and geographic factors as well as race and center size are associated with risk for the first peritonitis, independent of socioeconomic status, PD modality, and comorbidities.

Icodextrin does not impact infectious and culture-negative peritonitis rates in peritoneal dialysis patients: a 2-year multicentre, comparative, prospective cohort study.

BACKGROUND: Icodextrin is a glucose polymer derived by hydrolysis of cornstarch. The different biocompatibility profile of icodextrin-containing peritoneal dialysis (PD) solutions may have a positive influence on peritoneal host defence. Furthermore, cases of sterile peritonitis potentially associated with icodextrin have been reported. METHODS: The primary objective of this multicentre, longitudinal, observational, non-interventional, prospective cohort study, which included 722 PD patients, was to evaluate the incidence of overall peritonitis in patients treated with icodextrin-containing PD solutions (Extraneal) used during one long-dwell exchange/day compared with those treated with non-icodextrin-containing PD solutions. The secondary objective was to determine if culture-negative peritonitis rates differed between patients treated with icodextrin from two independent manufacturers. All peritonitis episodes were assessed by a Steering Committee in a blind manner. RESULTS: There was no significant difference between icodextrin-treated and control patients in the adjusted overall, culture-positive or culture-negative peritonitis rates. When stratified by the icodextrin supplier, there was no significant difference in the adjusted rate of culture-negative peritonitis episodes between groups. CONCLUSION: Subjects receiving icodextrin as part of their PD regimen experienced neither a higher rate of culture-negative peritonitis nor a lower rate of infectious peritonitis compared with non-icodextrin users. There was no significant influence of the icodextrin raw material supplier on peritonitis rates.

Longitudinal relationships between fluid status, inflammation, urine volume and plasma metabolites of icodextrin in patients randomized to glucose or icodextrin for the long exchange.

BACKGROUND: Randomized trials have shown that icodextrin reduces the volume of extra-cellular fluid (ECFv) with variable effects on residual renal function. To explore this fluid shift and its possible mechanisms in more detail, prospectively collected data from one such trial, including measures of inflammation (C-reactive protein, tumour necrosis factor-alpha, albumin and low and high molecular weight hyaluronan) ANP (atrial naturetic peptide), an indirect marker of intra-vascular volume, plasma concentrations of icodextrin metabolites and alpha-amylase activity were analysed. METHODS: 50 patients were randomized to either 2.27% glucose or icodextrin (n = 28) for a long exchange following a month run in. Blood samples were obtained at -1, 0, 3 and 6 months, coincident with measurements of urine volume and fluid status. RESULTS: In both randomized groups, a significant correlation between the fall in ECFv and the decline in urine volume was observed (P = 0.001), although the relative drop in urine volume for patients randomized to icodextrin tended to be less. At baseline, ANP was higher in patients with proportionately more ECFv for a given body water or height. Icodextrin patients had non-significantly higher ANP levels at baseline, whereas by 3 (P = 0.026) and 6 months (P = 0.016) these differed between groups due to divergence. There was a correlation between increasing ANP and reduced ECF at 3 months, r = -0.46, P = 0.007, in patients randomized to icodextrin, but not glucose. There were no relationships between fluid status and any inflammatory markers at any point of the study, with the exception of albumin at baseline, r = -0.39, P = 0.007. Amylase activities at -1 month and baseline were highly correlated, r = 0.89, P < 0.0001. Within patients, concentrations of icodextrin metabolites were highly correlated; the only predictor of between-patient variability on multivariate analysis was body weight. There was no relationship between plasma concentrations of icodextrin metabolites and any of the other clinical parameters, including change in daily ultrafiltration, urine volume, fluid or inflammatory status. CONCLUSIONS: This analysis supports observational data that changes in fluid status are associated with changes in urine volume. Icodextrin was not associated with a greater fall in urine output despite its larger effect on ECFv. Changes in fluid status could not be explained or did not appear to influence systemic inflammation. Nor can they be explained by individual variability in plasma concentrations of icodextrin that are in turn inversely proportional to the volume of distribution.

Automated peritoneal dialysis as the modality of choice: a single-center, 3-year experience with 458 children in Mexico.

Automated peritoneal dialysis (APD) has been considered as the ideal dialysis modality for pediatric patients. This study reports the 3-year APD experience with 458 end-stage renal disease (ESRD) children who started APD in a single pediatric center in Mexico City between June 2003 and June 2006. By June 2003, there were 310 patients being treated with continuous ambulatory peritoneal dialysis (CAPD). At that time, these patients were gradually switched to APD, with priority being given to those prescribed more than four exchanges per day, younger than 6 years of age, or presenting complications [hernias or decreased ultrafiltration (UF)]. An improvement of daily UF was observed when the patients were switched from CAPD (590 +/- 340 ml/day) to APD (846 +/- 335 ml/day). The presence of edema decreased (from 67% to 8%) as well as the percentage of patients requiring antihypertensive drugs (from 83% to 38%), the peritonitis rate improved from one episode every 35 patient/month to one episode every 47 patient/month, the total number of hospitalizations decreased (from 384 to 51), and 85% of children attended school. While waiting for renal transplant, APD is the dialysis modality of choice for ESRD children at the La Raza Medical Center in Mexico City.

Combination of crystalloid (glucose) and colloid (icodextrin) osmotic agents markedly enhances peritoneal fluid and solute transport during the long PD dwell.

BACKGROUND: Fluid and sodium removal is often inadequate in peritoneal dialysis patients with high peritoneal solute transport rate, especially when residual renal function is declining. METHOD: We studied the effects of using simultaneous crystalloid (glucose) and colloid (icodextrin) osmotic agents on the peritoneal transport of fluid, sodium, and other solutes during 15-hour single-dwell exchanges using 3.86% glucose, 7.5% icodextrin, and a combination fluid with 2.61% glucose and 6.8% icodextrin in 7 prevalent peritoneal dialysis patients with fast peritoneal solute transport rate. RESULTS: The combination fluid enhanced net ultrafiltration (mean 990 mL) and sodium removal (mean 158 mmol) compared with 7.5% icodextrin (mean net ultrafiltration 462 mL, mean net sodium removal 49 mmol). In contrast, the 3.86% glucose-based solution yielded negligible ultrafiltration (mean -85 mL) and sodium removal (mean 16 mmol). The combination solution resulted in significantly improved urea (+41%) and creatinine (+26%) clearances compared with 7.5% icodextrin. CONCLUSION: A solution containing both crystalloid (glucose 2.61%) and colloid (icodextrin 6.8%) osmotic agents enhanced fluid removal by twofold and sodium removal by threefold compared with 7.5% icodextrin solution during a dwell of 15 hours, indicating that such a combination solution could represent a new treatment option for anuric peritoneal dialysis patients with high peritoneal solute transport rate.

What is the link between poor ultrafiltration and increased mortality in anuric patients on automated peritoneal dialysis? Analysis of data from EAPOS.

BACKGROUND: Primary analysis of the European Automated Peritoneal Dialysis Outcomes Study (EAPOS) found that patients with daily ultrafiltration (UF) below a predefined target of 750 mL at baseline experienced increased mortality and continuing low UF over 2 years. SETTING: Multicenter, prospective observational study of prevalent, functionally anuric patients on automated peritoneal dialysis (APD) treated to predefined standards. METHODS: Secondary data analysis to determine clinical covariates that might support a link between poor UF and outcome, including pattern of comorbidity, prescription, nutrition as determined by Subjective Global Assessment (SGA), membrane function, and blood pressure (BP). Ultrafiltration was treated as a categorical (comparing patients above and below target at baseline) and continuous dependent variable in univariate and multivariate regression. The relationship between BP and survival was also explored. RESULTS: Of 177 patients recruited from 28 centers across Europe, 43 were below the UF target at baseline. Compared to those above target, there were no differences in the spread of comorbidity, type of APD prescription, SGA, BP, hemoglobin, HCO3, or parathyroid hormone, at baseline or at any later time. At baseline, plasma calcium and, at 12 months, plasma phosphate were lower in the low UF group. There was a weak positive correlation between baseline systolic or diastolic BP and UF, which remained on multivariate analysis but accounted for just 9% of the variability in BP. There was no clear relationship between baseline BP and survival, although, if anything, low BP was associated with earlier death. Poor UF was associated with lower mean dialysate glucose concentration during the first 4 months and with consistently worse membrane function. CONCLUSIONS: The increased mortality associated with poor UF is likely multifactorial and not easily explained by clear differences in comorbidity, nutritional state, or other indices of treatment at baseline. The lower plasma phosphate suggests a subsequent fall in appetite. Poor BP control is unlikely to be the explanation, and a link between lower BP, reduced UF, and earlier death is suggested. Failure to achieve adequate UF due to worse membrane function remains an important and potentially reversible or preventable cause.

Compatibility of insulin over 24 hours in standard and bicarbonate-based peritoneal dialysis solutions contained in bags made of different materials.

BACKGROUND: The purpose of this study was to evaluate potency changes in insulin in different solutions and bag materials used for peritoneal dialysis (PD). One of the PD solutions (Physioneal) tested is available in two different solution containers, PVC and Clear-Flex. Four insulin concentrations (4 IU/L, 10 IU/L, 20 IU/L, and 40 IU/L) were evaluated. This range of concentrations was defined in accordance with standard medical practice. All PD solutions made by Baxter, Castlebar, Ireland. METHODS: Insulin determination was performed by immunoassay (ELISA). RESULTS: In Dianeal, more than 90% of the initial dose of insulin remained available up to 24 hours for all concentrations tested. In Physioneal, for the higher concentrations tested (10 IU/L, 20 IU/L, and 40 IU/L), more than 90% of the initial dose of insulin remained available up to 6 hours, and more than 80% up to 24 hours. For the Lowest concentration of insulin tested in Physioneal (4 IU/L), more than 90% of the initial dose of insulin remained available up to 3 hours, and more than 70% up to 24 hours. Also for the lowest concentration of insulin, recovery correlated with the pH of the tested solutions. This effect became apparent over the storage time. CONCLUSIONS: The data show that insulin adsorption is less than 10% during the first 3 hours for every PD solution tested. Insulin recovery tends to be stable or to decrease slightly over time for the lower insulin concentrations tested. The results for insulin recovery show a correlation with insulin concentration and with pH for the lowest insulin dose tested. From a solution-container interaction perspective, Clear-Flex is an equivalent alternative to standard PVC material.

Inflammation contributes to low plasma amino acid concentrations in patients with chronic kidney disease.

BACKGROUND: Inflammation and malnutrition are common in chronic kidney disease (CKD) patients, and plasma concentrations of free amino acids (AAs) in these patients are often abnormal. Malnutrition contributes to alterations in AA concentrations. OBJECTIVE: The objective was to study the effects of inflammation on plasma AA concentrations. DESIGN: Concentrations of plasma AAs, serum albumin, and several inflammatory markers were analyzed in 200 fasting, nondiabetic CKD patients who were close to the start of renal replacement therapy. The nutritional status of these patients was assessed by a subjective global assessment. RESULTS: The patients with inflammation [C-reactive protein (CRP) concentrations >10 mg/L] or malnutrition had lower AA concentrations than did the patients with no inflammation or malnutrition. The presence of both inflammation and malnutrition was associated with more marked reductions in AA concentrations than was malnutrition alone. Significant inverse correlations were observed between the plasma concentrations of most of the essential and nonessential AAs and inflammatory markers, whereas serum albumin concentrations were positively correlated with several AA concentrations. A stepwise multivariate regression analysis showed that serum CRP concentrations were independently associated with low concentrations of the sums of both nonessential AAs and all AAs. An analysis of all-cause mortality with a Kaplan-Meier test showed that the patients with higher AA concentrations had significantly better survival than did the patients with lower AA concentrations. CONCLUSIONS: Plasma AA concentrations are low in CKD patients with inflammation and are inversely correlated with concentrations of inflammatory markers. Although inflammation and malnutrition are closely related, CRP concentrations were independently associated with low concentrations of the sums of both nonessential AAs and all AAs, which suggests an independent role of inflammation as a cause of low plasma AA concentrations in CKD patients.

Survival of functionally anuric patients on automated peritoneal dialysis: the European APD Outcome Study.

The European APD Outcome Study (EAPOS) is a 2-yr, prospective, multicenter study of the feasibility and clinical outcomes of automated peritoneal dialysis (APD) in anuric patients. A total of 177 patients were enrolled with a median age of 54 yr (range, 21 to 91 yr). Previous median total time on dialysis was 38 mo (range, 1.6 to 259 mo), and 36% of patients had previously been on hemodialysis for >90 d. Diabetes and cardiovascular disease were present in 17% and 46% of patients, respectively. The APD prescription was adjusted at physician discretion to aim for creatinine clearance (Ccrea) >/=60 L/wk per 1.73 m(2) and ultrafiltration (UF) >/=750 ml/24 h during the first 6 mo. Baseline solute transport status (D/P) was determined by peritoneal equilibration test. At 1 yr, 78% and 74% achieved Ccrea and UF targets, respectively; median drained dialysate volume was 16.2 L/24 h with 50% of patients using icodextrin. Baseline D/P was not related to UF achieved at 1 yr. At 2 yr, patient survival was 78% and technique survival was 62%. Baseline predictors of poor survival were age (>65 yr; P = 0.006), nutritional status (Subjective Global Assessment grade C; P = 0.009), diabetic status (P = 0.008), and UF (<750 ml/24 h; P = 0.047). Time-averaged analyses showed that age, Subjective Global Assessment grade C and diabetic status predicted patient survival with UF the next most significant variable (risk ratio, 0.5/L per d; P = 0.097). Baseline Ccrea, time-averaged Ccrea, and baseline D/P had no effect on patient or technique survival. This study shows that anuric patients can successfully use APD. Baseline UF, not Ccrea or membrane permeability, is associated with patient survival.

Icodextrin improves the fluid status of peritoneal dialysis patients: results of a double-blind randomized controlled trial.

Worsening fluid balance results in reduced technique and patient survival in peritoneal dialysis. Under these conditions, the glucose polymer icodextrin is known to enhance ultrafiltration in the long dwell. A multicenter, randomized, double-blind, controlled trial was undertaken to compare icodextrin versus 2.27% glucose to establish whether icodextrin improves fluid status. Fifty patients with urine output <750 ml/d, high solute transport, and either treated hypertension or untreated BP >140/90 mmHg, or a requirement for the equivalent of all 2.27% glucose exchanges, were randomized 1:1 and evaluated at 1, 3, and 6 mo. Members of the icodextrin group lost weight, whereas the control group gained weight. Similar differences in total body water were observed, largely explained by reduced extracellular fluid volume in those receiving icodextrin, who also achieved better ultrafiltration and total sodium losses at 3 mo (P < 0.05) and had better maintenance of urine volume at 6 mo (P = 0.039). In patients fulfilling the study's inclusion criteria, the use of icodextrin, when compared with 2.27% glucose, in the long exchange improves fluid removal and status in peritoneal dialysis. This effect is apparent within 1 mo of commencement and was sustained for 6 mo without harmful effects on residual renal function.

Clinical experience with a new bicarbonate (25 mmol/L)/lactate (10 mmol/L) peritoneal dialysis solution.

OBJECTIVE: Physiological bicarbonate/lactate-based solutions may correct acidosis in a better way than standard lactate-based solutions. In this study, a new 25 mmol/L bicarbonate/10 mmol/L lactate peritoneal dialysis (PD) solution was compared with a standard 35 mmolL lactate solution. DESIGN: This was a prospective open label study. All patients had a 2-week baseline period using the standard lactate solution, followed by 8 weeks on the bicarbonate/ lactate solution and 2 weeks on the lactate-based solution. SETTING: Four Danish and four Spanish nephrology centers. PATIENTS: 40 well-dialyzed (creatinine clearance > 55 L/week/1.73 m2 body surface area) patients on continuous ambulatory PD. INTERVENTIONS: Blood samples were taken for biochemistry (including venous blood gases) at week -2, day 1, weeks 2, 4, and 8, and at follow-up. A physical examination, a peritoneal equilibration test (PET), and quality of life (K/DQOL), ultrafiltration, and adequacy assessments were performed at baseline and at week 8. Vital signs and other safety parameters were followed at each visit. Extraneal (Baxter Healthcare, Castlebar, Ireland) was used by all patients for the long dwell. MAIN OUTCOME MEASURE: Effect on the venous plasma bicarbonate level. RESULTS: Venous plasma bicarbonate levels rose from 24.4 mmol/L when patients were on the pure lactate to 26.1 mmol/L when using the bicarbonate/lactate solution (p < 0.001). When patients were using the bicarbonate/ lactate solution, 66% of values were maintained within the venous normal range of 24-30 mmol/L, versus 46.2% when patients were on the pure lactate solution (p < 0.001). There were no adverse findings with respect to clinical symptoms, vital signs, or physical examination. The PET and adequacy, ultrafiltration, and K/DQOL assessment results were unchanged. CONCLUSIONS: The new 25 mmol/L bicarbonate/ 10 mmol/L lactate solution provided better correction of acidosis than an equivalent 35 mmol/L standard lactate solution, without any safety issues.

Extracellular volume changes and blood pressure levels in hemodialysis patients.

BACKGROUND: Despite the use of highly efficient antihypertensive drugs (AHD), blood pressure (BP) is poorly controlled in the vast majority of hemodialysis (HD) patients. Many of them show no reduction in nocturnal BP, a finding that is associated with left ventricular hypertrophy. The aim of the study was to investigate the effect of the removal of a fluid overload on BP by monitoring the ambulatory BP during 48 hours in 16 hypertensive HD patients treated with AHD. Our aim was to obtain a gradual reduction in post-HD body weight (BW) over a period of 3 to 4 months. METHODS: During a period of 3-4 months, the postdialysis BW was reduced as the minimal tolerable BW was gradually achieved by slightly increasing the ultrafiltration volume. The Na concentration in the dialysate was reduced from 143-141 mmol/L to 139-138 mmol/L. Extracellular volume (ECV) was measured with a multiple-frequency bioimpedance analyzer (Xitron 4000B, Xitron Technologies Inc., San Diego, CA, USA). Based on the change in ECV, the patients were subdivided into two groups: group 1 with a reduction in ECV (n = 10), and group 2 with no reduction (n = 6). At the start of the study, BW, BP, and AHD in group 1 and group 2 were virtually identical. RESULTS: Group 1 showed a significant reduction during the entire 48-hour period in systolic (156 +/- 16 mmHg vs. 140 +/- 14 mmHg, P = 0.030) and diastolic BP (97 +/- 12 mmHg vs. 87 +/- 9 mmHg, P = 0.026) as well as in mean arterial pressure (MAP, 117 +/- 13 vs. 105 +/- 10 mmHg, P = 0.027). This reduction was more marked during the night (systolic BP 156 +/- 15 mmHg vs. 138 +/- 14 mmHg, P = 0.007; diastolic BP 97 +/- 12 mmHg vs. 85 +/- 9 mmHg, P = 0.009) than during the day (157 +/- 18 mmHg vs. 142 +/- 15 mmHg, P = 0.067; diastolic BP 97 +/- 13 mmHg vs. 90 +/- 9 mmHg, P = 0.126). A significant reduction in systolic load also occurred during the entire 48-hour period (76 +/- 24% vs. 46 +/- 28%, P = 0.043) as well as in night systolic load (75 +/- 21% vs. 41 +/- 30%, P = 0.015) and night diastolic load (67 +/- 32% vs. 39 +/- 31%, P = 0.030). AHD were stopped in eight and reduced in two patients. There were no significant reductions in BP and AHD in group 2. CONCLUSIONS: The removal of excess fluid is necessary for adequate BP control and especially for the reduction in elevated BP during the night.