Risk factors associated with mortality among patients on maintenance hemodialysis: The Thailand Renal Replacement Therapy registry.

INTRODUCTION: End-stage kidney disease (ESKD) has been increasing in prevalence across the world, including Thailand, and patients with ESKD on hemodialysis have a high mortality risk. METHODS: A retrospective cohort study was performed across 855 hemodialysis centers in the Thailand Renal Replacement Therapy registry. The database and mortality data were analyzed. RESULTS: A total of 58 952 patients were included. The survival rates at 1, 3, and 5 years were 93.5%, 69.7%, and 41.2%, respectively. On multivariate analysis, factors such as aging, permanent catheter or arteriovenous graft, twice-weekly hemodialysis, low levels of urea reduction ratio, normalized protein catabolic rate, hemoglobin, transferrin saturation, serum albumin, LDL-cholesterol, intact-parathyroid hormone, uric acid, sodium, phosphate, and bicarbonate were significantly related to death. CONCLUSION: Mortality is high in ESKD patients on hemodialysis. Age, type of vascular access, twice-weekly hemodialysis, inadequate dialysis, low protein intake, anemia, abnormal electrolytes, and bone mineral disorders are associated with all-cause mortality.

Comparison of citrate dialysate in pre- and post-dilution online hemodiafiltration: effect on clot formation and adequacy of dialysis in hemodialysis patients.

BACKGROUND: Citrate dialysate (CD) has been successfully used in conventional hemodialysis and continuous renal replacement therapy; however, no study has compared pre- and post-dilution online hemodiafiltration (oL-HDF). Therefore, we aimed to investigate the efficacy of citrate anticoagulation for oL-HDF and the metabolic changes and quality of life of patients on hemodialysis treated using both modes. METHOD: Eight dialysis patients were treated with CD containing 0.8 mmol of citric acid for 4 weeks in each phase. Visual clotting scores were investigated as the primary endpoints. Adequacy of dialysis, laboratory parameters, and quality of life were measured as secondary objectives. RESULTS: The mean clotting scores in the pre-dilution mode were significantly lower than those in the post-dilution mode and in all phases except the heparin-free phase (p < 0.001 in the baseline phase, p = 0.001 in phase 1, and p = 0.023 in phase 2). The values of Kt/V in both modalities were comparable except during the baseline phase, in which the values of pre-dilution were significantly greater than post-dilution (2.36 ± 0.52/week vs. 1.87 ± 0.33/week;95% CI -0.81 to -0.19, p = 0.002). The patient's quality of life regarding their physical activity level was significantly higher in the post-dilution mode than in the pre-dilution mode at baseline and in phase 1 (p = 0.014 and 0.004 at baseline and in phase 1, respectively). Metabolic changes did not differ between the two modes. CONCLUSION: Citrate dialysate decreased or prevented anticoagulation in both pre- and post-dilution modes of oL-HDF without significant side effects and had comparable adequacy of dialysis.

Long term reduction of cardiovascular risk factors associated with three hour daily dialysis: A prospective, cohort study.

INTRODUCTION: Daily hemodialysis (DHD) compared to conventional hemodialysis (CHD) leads to improvements in left ventricular hypertrophy and mineral metabolism at 1-year follow-up. However, there is no information from prospective studies on the long terms effects of DHD on these key cardiovascular risk factors. METHODS: We conducted a 4 year, prospective cohort study of 26 DHD and 51 matched CHD patients on the effect of DHD (six sessions/week × 3 h) versus CHD (three sessions/week × 4 h), 15 DHD, and 26 CHD patients completed 4-years follow-up. Measures of left ventricular mass index (LVMI), blood pressures, hemoglobin, and mineral metabolism markers were performed. RESULTS: Systolic and diastolic blood pressures were significantly lower in the DHD group than the CHD group at 4-year follow-up, 128 mmHg (95% CI, 111-143) versus 148 mmHg (95% CI, 137-158) (p < 0.05) and 60 mmHg (95% CI, 56-63) versus 71 mmHg (95% CI, 64-76) (p < 0.05). DHD was associated with fewer patients taking any anti-hypertensive drug therapy than CHD, 50% versus 80% (p < 0.05). DHD was associated with improved attainment of mineral metabolism goals for phosphorus (adjusted HR 3.6, p = 0.002) and calcium × phosphorus product (adjusted HR 3.66, p = 0.001) at 4-years follow-up compared to CHD. At 4 years, there was a nonsignificant trend toward lower LVMI in the DHD than in the CHD group: 116 g/m2 (95% CI, 97-136) versus 138 g/m2 (95% CI, 115-172) (p = 0.23). Similarly, improvements in hemoglobin also persisted at 4 years follow-up. CONCLUSION: DHD is associated with long-term (4 year) improvements in key cardiovascular risk factors: blood pressure, mineral metabolism, and anemia with trends toward improved LVMI.

The Relationship between Serum Procalcitonin and Dialysis Adequacy in Peritoneal Dialysis Patients.

BACKGROUND: To detect the serum procalcitonin (PCT) levels of peritoneal dialysis (PD) patients. METHODS: We analyzed the relationship between the PCT Level and dialysis adequacy. We studied 120 peritoneal dialysis patients without signs of infection in Affiliated Hangzhou First People's Hospital and 120 controls from Jan 2014 to Apr 2016. PCT and high sensitivity C-reactive protein (hs-CRP) were detected. 120 PD patients were divided into two groups according to the dialysis adequacy. A correlation analysis was processed between the PCT level and the total solute clearance (Kt/V). The value of PCT for identifying the dialysis adequacy in PD patients was assessed by ROC curve analysis. RESULTS: PCT level in serum of PD group (0.29±0.24 ng/ml) was higher than that of the control group (0.02±0.01 ng/ml) (P<0.01). Compared with the inadequate dialysis group (0.5±0.37 ng/ml), the PCT Level of the adequate dialysis group (0.23±0.15 ng/ml) was lower (P<0.01). There were negative correlations between PCT and Kt/v(r=-0.451), Prealbumin (PA) (r=-0.258), Glomerular Filtration Rate (eGFR; r=-0.280), while there was positive correlation between PCT and Hypersensitive c-reactive protein (r=0.458) (P<0.01). At a serum PCT cut-off value of 0.283 ng/ml, the sensitivity and specificity for identifying the dialysis adequacy in PD patients were 0.913 and 0.805 respectively. The serum levels of PCT in peritoneal dialysis patients were significantly higher than the levels in healthy controls. CONCLUSION: The serum level of PCT can be used as an indirect maker to evaluate the adequacy of dialysis.

Half the V by 120: A practical approach to the prevention of the dialysis disequilibrium syndrome.

The dialysis disequilibrium syndrome (DDS) results from osmotic shifts between the blood and the brain compartments. Patients at risk for DDS include those with very elevated blood urea nitrogen, concomitant hypernatremia, metabolic acidosis, and low total body water volumes. By understanding the underlying pathophysiology and applying urea kinetic modeling, it is possible to avoid the occurrence of this disorder. A urea reduction ratio (URR) of no more than 40%-45% over 2 h is recommended for the initial hemodialysis treatment. The relationship between the URR and Kt/V is useful when trying to model the dialysis treatment to a specific URR target. A simplified relationship between Kt/V and URR is provided by the equation: Kt/V = -ln (1 - URR). A URR of 40% is roughly equivalent to a Kt/V of 0.5. The required dialyzer urea clearance to achieve this goal URR in a 120-min treatment can simply be calculated by dividing half the patient's volume of distribution of urea by 120. The blood flow rate and dialyzer mass transfer coefficient (K0 A) required to achieve this clearance can then be plotted on a nomogram. Other methods to reduce the risk of DDS are reviewed, including the use of continuous renal replacement therapy.

Is Twice-weekly Maintenance Hemodialysis Justified?

BACKGROUND: The benefits of twice-weekly dialysis at initiation are significant with respect to access longevity, preservation of residual renal function, economic factors, and patient quality of life. It is widely practiced in developing countries due to resource and financial constraints. We present a 3-year follow-up of patients on twice-weekly dialysis and their outcomes. MATERIAL AND METHODS: This was a 3-year observational follow-up study of patients initiated on twice-weekly hemodialysis. Adequacy and basic cost-effective hematological and biochemical parameters were studied monthly. In case of complications, the patient was shifted to thrice-weekly hemodialysis. RESULTS: 88 incident hemodialysis patients were followed up. Total sessions of hemodialysis (HD) studied were 16,406. The mean hemoglobin level was 9.53 g/dl with hyperphosphatemia in 74.88% patients. The mean residual renal function (RRF) at initiation was 5.71 +/- 3.70 ml/min. The mean interdialytic weight gain was 1.91 +/- 1.26 kg with a mean ultrafiltration of 2600 ± 410 ml. The spKt/V and eKt/V were adequate in 68.54% and 48.34% patients; however, the standard Kt/V of 2 was achieved in only 10.51% patients. Emergency HD was done in 41 sessions (0.24%). There were 24 deaths (27.27%) during this period with the mean time to mortality being 503.12 +/- 296.62 days. CONCLUSION: Initiation at twice-weekly schedules for patients on maintenance hemodialysis is a viable option with increments in case of requirement, more so in patients with good urine output and residual renal function. The biochemical and hematological parameters were stable and within KDOQI guidelines and do not worsen with time.

Effects of hemodialysis access surveillance on reducing risk of hemodialysis access thrombosis: A meta-analysis of randomized studies.

INTRODUCTION: Vascular access thrombosis remains the Achilles Heel for many a hemodialysis patient. We performed a systematic review and meta-analysis to assess the impact of monitoring vascular access blood flow on prediction and prevention of vascular access thrombosis. We hypothesized that monitoring vascular access blood flow has a pivotal role in lowering the risk of thrombosis and subsequent access failure. METHODOLOGY: We conducted a systematic review in PubMed and EMBASE databases to identify randomized studies that have assessed the effect of hemodialysis access surveillance on the risk of thrombosis. A random-effects model was used for the meta-analysis. Subgroup analysis was performed among patients with arterio-venous fistula (AV-fistulas) and those with arterio-venous graft (AV-grafts). RESULTS: Ten randomized studies were included in the meta-analysis. The total number of patients included in the analysis was 1430. On performing the random-effects model among the included studies, hemodialysis access surveillance was associated with better outcomes (risk ratio = 0.73, 95% confidence interval ranges from 0.55 to 0.98). The analysis of the AV-fistula group showed an estimated overall risk ratio of 0.55 (95% confidence interval ranges from 0.33 to 0.89) favoring access surveillance. However, in the AV-grafts group, the estimated overall risk ratio was 0.92 (95% confidence interval ranges from 0.65 to 1.29) showing no additional benefit for access surveillance. CONCLUSION: Hemodialysis access surveillance using access blood flow monitoring can reduce the risk of access thrombosis for patients with AV-fistulas, but this is not the case with AV-grafts.

The association of standard Kt/V and surface area-normalized standard Kt/V with clinical outcomes in hemodialysis patients.

INTRODUCTION: A previous study demonstrated that the surface area-normalized standard Kt/V (SAstdKt/V) was better associated with mortality than standard Kt/V (stdKt/V). This study investigates the association of SAstdKt/V and stdKt/V with mortality, anemia, and hypoalbuminemia in a larger patient cohort with a longer follow-up period. METHODS: We included adult patients on thrice-weekly hemodialysis in the USRDS database and excluded amputated patients. StdKt/V and SAstdKt/V were calculated from the available single-pool Kt/V. Patients were categorized into five groups according to their stdKt/V and SAstdKt/V: <2.00, 2.00-2.19, 2.20-2.39, 2.40-2.59, and ≥2.60. Hazard ratios (HR) and odds ratios (OR) were calculated using Cox and logistic regression analysis respectively. FINDINGS: There were 507,656 patients included in the analysis. The patients had a median age of 65.5 years with a median follow-up period of 2 years. Thirty-four percent died during follow-up. HRs for mortality progressively decreased as SAstdKt/V increased in both unadjusted and adjusted models. Unlike SAstdKt/V, HRs were the lowest in the categories with stdKt/V of 2.40-2.59 and they increased in the higher stdKt/V category. The adjusted HR for SAstdKt/V vs. stdKt/V were 0.68 vs. 0.62 in the category of 2.40-2.59, and 0.63 vs. 0.73 in the category of ≥2.60. The adjusted ORs for anemia progressively decreased as SAstdKt/V increased, whereas ORs decreased to the lowest in stdKt/V category 2.40-2.59 and increased in the ≥2.60 category. The adjusted ORs for hypoalbuminemia progressively decreased as SAstdKt/V and stdKt/V increased which were both 0.45 in 2.40-2.59 category and decreased to 0.29 and 0.42 in the ≥2.60 category. DISCUSSION: SAstdKt/V is better associated with mortality, anemia, and hypoalbuminemia than stdKt/V. SAstdKt/V is a better parameter in defining hemodialysis dosing which can be calculated by an available online tool. Further studies to determine the optimal SAstdKt/V dose required to achieve improved clinical outcomes with better cost-effectiveness are needed.

Intradialytic exercise with blood flow restriction: Something to add to hemodialysis adequacy? Findings from a crossover study.

INTRODUCTION: Hemodialysis (HD) increases the lifespan of chronic kidney disease (CKD) patients. However, HD is only partially effective in replacing renal function. The aim of this study is to compare HD adequacy between sessions with intradialytic exercise with or without blood flow restriction (BFR) with sessions without exercise. METHODS: A crossover study including 22 adult CKD patients on HD. The patients were assigned to BFR (n = 11) or exercise alone group (n = 11). Each patient was submitted to four HD sessions (two with exercise and two control sessions). HD adequacy was assessed by equilibrated Kt/V-urea (eKT/V), single-pool Kt/V-urea (sp-Kt/V), urea and phosphorus rebound, urea reduction ratio (URR) and removal of urea and phosphorus in dialysate. FINDINGS: BFR exercise improved eKt/V and sp-Kt/V (1.32 ± 0.21 vs. 1.10 ± 0.16 for control, P < 0.001; 1.53 ± 0.26 vs. 1.27 ± 0.19 for control, P < 0.001, respectively) and URR (72.5 ± 5.4% vs. 66.1 ± 7.7% for control, P < 0.001). No difference in eKt/V, sp-Kt/V or URR could be detected between exercise alone and control HD sessions. Urea rebound was lower in BFR exercise vs. control sessions (-8.9 ± 9.1% vs. 30.7 ± 12.8%, P < 0.01) and exercise alone vs. control sessions (13.3 ± 29.0% vs. 42.4 ± 15.3%, P < 0.01). Phosphorus rebound was marginally lower in exercise vs. control sessions (14.4 ± 19.1% vs. 28.4 ± 22.1%, P = 0.18). Urea and phosphorus mass removal in dialysate were marginally higher in exercise vs. control sessions (42.2 ± 19.4 g vs. 35.7 ± 12.5 g, P = 0.24; 912.1 ± 360.9 mg vs. 778.6 ± 245.1 mg, P = 0.28). CONCLUSIONS: Intradialytic exercise with BFR was more effective than standard exercise in increasing HD adequacy.

Safety and efficacy of the Tablo hemodialysis system for in-center and home hemodialysis.

INTRODUCTION: Home hemodialysis remains underutilized despite observational data indicating more favorable outcomes with home compared with in-center hemodialysis. The Tablo Hemodialysis system is designed to be easy to learn and use and to facilitate adoption of home hemodialysis. The objective of the current investigational device exemption (IDE) study was to evaluate the safety and efficacy of Tablo managed in-center by health care professionals and in-home by patients and/or caregivers. METHODS: A prospective, multicenter, open-label, crossover trial comparing in-center and in-home hemodialysis using Tablo. There were 4 treatment periods during which hemodialysis was prescribed 4 times per week: 1-week Run-In, 8-week In-Center, 4-week Transition, and 8-week In-Home. The primary efficacy endpoint was weekly standard Kt/Vurea ≥ 2.1. The secondary efficacy endpoint was delivery of ultrafiltration (UF) within 10% of prescribed UF. We collected safety and usability data. FINDINGS: Thirty participants enrolled and 28 completed all trial periods. Adherence to the protocol requirement of 4 treatments per week was 96% in-center and 99% in-home. The average prescribed and delivered session lengths were 3.4 hours for both the In-Center and the In-Home periods. The primary efficacy endpoint for the intention-to-treat cohort was achieved in 199/200 (99.5%) of measurements during the In-Center period and 168/171 (98.3%) In-Home. The average weekly standard Kt/Vurea was 2.8 in both periods. The secondary efficacy UF endpoint was achieved in the ITT cohort in 94% in both in-center and in-home. Two prespecified adverse events (AEs) occurred during the In-Center period and 6 in the In-Home period. None of the AEs were deemed by investigators as related to Tablo. The median resolution time of alarms was 8 seconds in-center and 5 seconds in-home. CONCLUSION: Primary and secondary efficacy and safety endpoints were achieved during both In-Center and In-Home trial periods. This study confirms that Tablo is safe and effective for home hemodialysis use.

Calculating Standard Kt/V during Hemodialysis Based on Urea Mass Removed.

BACKGROUND/AIMS: We derived a novel equation for calculating weekly urea standard Kt/V (stdKt/V) during hemodialysis (HD) based on urea mass removed, comparable to the approach during peritoneal dialysis. METHODS: Theoretical consideration of urea mass balance during HD led to the following equation for stdKt/V, namely, stdKt/V = N × (URR + UFV/V), where N is the number of treatments per week, URR is urea reduction ratio per treatment, UFV is ultrafiltration volume per treatment, and V is postdialysis urea distribution volume. URR required corrections for postdialysis rebound and intradialytic urea generation. We compared the accuracy of this approach with previous equations for stdKt/V by numerical simulations using a 2-compartment model of urea kinetics for thrice-weekly and more frequent HD prescriptions. RESULTS: The proposed equation based on urea mass removed predicted values of stdKt/V that are equivalent to those calculated by previous equations for stdKt/V. CONCLUSION: This work provides a novel approach for calculating stdKt/V during HD and strengthens the theoretical understanding of stdKt/V.

Kinetics of acid-base parameters in conventional hemodialysis

Details about the acid-base changes in hemodialysis are scarce in the literature but are potentially relevant to adequate management of patients. We addressed the acid-base kinetics during hemodialysis and throughout the interdialytic period in a cross-sectional study of adults undergoing conventional hemodialysis. Samples for blood gas analysis were obtained from the arterial limb of the arteriovenous fistula before the first session of the week (HD1), immediately at the end of HD1, and on sequential collections at 15, 30, 45, 60, and 120 min post-HD1. Additional blood samples were collected after ∼20 h following the end of the first dialysis and immediately prior to the initiation of the second dialysis of the week. Thirty adult patients were analyzed (55±15 years, 50% men, 23% diabetic; dialysis vintage 69±53 months). Mean serum bicarbonate levels increased at the end of HD1 (22.3±2.7 mEq/L vs 17.5±2.3 mEq/L, P<0.001) and remained stable until 20 h after the end of the session. The mean values of pCO2 before HD1 were below reference and at 60 and 120 min post-HD1 were significantly lower than at the start (31.3±2.7 mmHg and 30.9±3.7 mmHg vs 34.3±4.1 mmHg, P=0.041 and P=0.010, respectively). The only point of collection in which mean values of pCO2 were above 35 mmHg was 20 h post-dialysis. Serum bicarbonate levels remained stable for at least 20 h after the dialysis sessions, a finding that may have therapeutic implications. During dialysis, the respiratory response for correction of metabolic acidosis (i.e., pCO2 elevation) was impaired.

Online measurement of hemodialysis adequacy using effective ionic dialysance of sodium-a review of its principles, applications, benefits, and risks.

Dialysis dose is an important determinant of clinical outcomes in patients with end stage renal disease on maintenance dialysis. In clinical practice dialysis dose is monitored at least monthly by urea clearance based on Urea Kinetic Modeling. Online clearance monitoring using effective ionic dialysance (EID) of sodium (Na+ ) is available on some hemodialysis machines. This paper reviews the background, methodology, additional applications, and potential risks associated with EID. Effective ionic dialysance provides a reliable, real-time, noninvasive, and inexpensive measurement of dialysis dose during an ongoing hemodialysis (HD) session to allow interventions and assess the impact of these changes on clearance. Surveillance of vascular access flow rates can be used to screen for access dysfunction and refer for interventions. There is a concern that EID measurements may cause Na+ loading because of high dialysate Na+ used during these measurements, however, mathematical models, in vitro experiments, and clinical studies in patients on maintenance HD do not show any evidence of Na+ loading during EID measurements. We cannot rule out the possibility of nonosmotic Na+ accumulation in the skin because no published literature exists on this topic as it pertains to clearance measurements based on EID of Na+ .

Effect of body composition on dialysis quality(Kt/V): a single center study / 中华肾脏病杂志

Objective To investigate the relationship between body composition and adequacy of dialysis,and analyze the related risk factors for inadequate delivery of hemodialysis.Methods In a prospective clinical trial,two different methods determining dialysis dose were simultaneously applied:Kt/Vdau (conventional method with Daugirdas' formula) and Kt/Vbem [online clearance monitoring (OCM) measurement with Ⅴ measured by body composition monitor (BCM)].Using the value of 1.27 as the boundary,the patients were divided into two groups:Kt/Vbcm ＜ 1.27 group and Kt/Vbcm≥ 1.27 group.Clinical indices were compared between the two groups.Multiple linear regression was applied to analyze the potential impact factors of the difference between Kt/V values calculated by the two methods.Receiver operator characteristic (ROC) curve was applied to analyze meaningful factors.Results A total of 138 maintenance hemodialysis patients with age of (54.9±12.7) years old were enrolled,and 55.1％ of them were males.There was no significant difference between Kt/Vdau and Kt/Vbcm [1.432(1.235,1.718) vs 1.434 (1.244,1.642),P=0.823].Kt/Vdau was incidentally prone to falsely high values due to operative errors,whereas in these cases OCM-based measurement Kt/Vbcm delivered realistic values.An excellent correlation was observed between Kt/Vdau and Kt/Vbcm;the mean difference was 0.07,95％CI (-0.66-0.79);the correlation coefficient was 0.842(0.821-0.862).The patients in Kt/Vbcm≥ 1.27 group had older age,lower body mass index (BMI),lower height and weight,lower total body water (TBW),lower extracellular water,lower intracellular water,and lower lean tissue index (LTI) compared to those in Kt/Vbcm ＜ 1.27 group.Excellent correlations were observed between Kt/Vbcm and TBW or LTI (r=-0.834,P ＜ 0.001;r=-0.721,P ＜ 0.001).ROC curve analysis showed that the sensitivity and specificity of predicting inadequate delivery of hemodialysis were 87.1％ and 86.5％,with a threshold of 30 L for TBW.It also showed that the sensitivity and specificity of predicting inadequate delivery of hemodialysis were 60.4％ and 94.6％,with a threshold of 11.05 kg/m2 for LTI.Conclusions BCM can give more accurate parameters of urea distribution volume,thus modifying the result of Kt/V.TBW and LTI are important risk influencing factors for inadequately dialysis,and special attention should be paid to patients with TBW ＞ 30 L or LTI ＞ 11.05 kg/m2.

Bioimpedance monitoring of cellular hydration during hemodialysis therapy.

Introduction The aim of this paper is to describe and demonstrate how a new bioimpedance analytical procedure can be used to monitor cellular hydration of End Stage Renal Disease (ESRD) patients during hemodialysis (HD). Methods A tetra-polar bioimpedance spectroscope (BIS), (UFI Inc., Morro Bay, CA), was used to measure the tissue resistance and reactance of the calf of 17 ESRD patients at 40 discrete frequencies once a minute during dialysis treatment. These measurements were then used to derive intracellular, interstitial, and intravascular compartment volume changes during dialysis. Findings The mean (± SD) extracellular resistance increased during dialysis from 92.4 ± 3.5 to 117.7 ± 5.8 Ohms. While the mean intracellular resistance decreased from 413.5 ± 11.7 to 348.5 ± 8.2 Ohms. It was calculated from these data that the mean intravascular volume fell 9.5%; interstitial volume fell 33.4%; and intracellular volume gained 20.3%. Discussion These results suggest that an extensive fluid shift into the cells may take place during HD. The present research may contribute to a better understanding of how factors that influence fluid redistribution may affect an ESRD patient during dialysis. In light of this finding, it is concluded that the rate of vascular refill is jointly determined with the rate of "cellular refill" and the transfer of fluid from the intertitial compartment into the intravascular space.

Vascular refilling is independent of volume overload in hemodialysis with moderate ultrafiltration requirements.

Introduction Blood volume changes and vascular refilling during hemodialysis (HD) and ultrafiltration (UF) have been assumed to depend on volume overload (Vo ). It was the aim to study the magnitude of vascular refilling in stable HD patients with moderate volume expansion in everyday dialysis using novel technical approaches. Methods Patients were studied during routine dialysis and UF based on clinical dry weight assessment. Pre-dialysis Vo was independently measured by bioimpedance spectroscopy. Vascular refilling volume (Vref ) was calculated as: Vref = Vuf - ΔV, where ΔV is the absolute blood volume change determined by on-line dialysate dilution using a commercial on-line hemodiafiltration machine incorporating a relative blood volume monitor, and where Vuf is the prescribed UF volume. Findings Thirty patients (dry weight: 81.0 ± 17.8 kg) were studied. Pre-dialysis Vo was 2.46 ± 1.45 L. Vuf was 2.27 ± 0.71 L, specific UF rate was 6.45 ± 2.43 mL/kg/h, and since ΔV was 0.66 ± 0.31 L, Vref was determined as 1.61 ± 0.58 L, corresponding to a constant refilling fraction (Fref ) of 70.6 ± 10.6%. Vref strongly correlated with Vuf (r(2) = 0.82) but was independent of Vo and other volumes. Fref was also independent of Vo and other volumes normalized for various measures of body size. Discussion While vascular refilling and Fref is independent of Vo in treatments with moderate UF requirements, intravascular volume depletion increases with increasing UF requirements. The relationship between blood volume and Vo needs to be more closely examined in further studies to optimize volume control in everyday dialysis.

Chronic Hemodialysis Therapy in the West.

BACKGROUND: Chronic hemodialysis (HD) in the 1960s encompassed a wide variety of prescriptions from twice weekly to five times per week HD. Over time, HD prescriptions in the West became standardized at three times per week, 2.5-4 h per session, with occasional additional treatments for volume overload. SUMMARY: When clinical trials of dialysis dose failed to show significant benefit of extending time compared with the traditional dialysis prescription, interest in more frequent HD was renewed. Consequently, there has been growth in home HD therapies as well as alternative dialysis prescriptions. Data from recent randomized clinical trials have demonstrated the benefits and risks of these more frequent therapies, with surprising differences in outcomes between short daily HD and long nocturnal HD. More frequent therapies improve control of both hypertension and hyperphosphatemia, but at the expense of increased vascular access complications and, at least for nocturnal HD, a faster loss of residual renal function. KEY MESSAGES: In the West, the standard HD prescription is three treatments per week with a minimal time of 3.0 h and dialysis is performed in an outpatient dialysis center. A minority of patients will have a fourth treatment per week for volume issues. Alternative HD prescriptions, although rare, are more available compared to the recent past. FACTS FROM EAST AND WEST: (1) While developed Western and Asian countries provide end-stage renal disease patients full access to HD, healthcare systems from South and South-East Asia can offer access to HD only to a limited fraction of the patients in need. Even though the annual costs of HD are much lower in less developed countries (for instance 30 times lower in India compared to the US), patients often cannot afford costs not covered by health insurance. (2) The recommended dialysis pattern in the West is at least three sessions weekly with high-flux dialyzers. Studies from Shanghai and Taiwan might however indicate a benefit of twice versus thrice weekly sessions. In less developed Asian countries, a twice weekly pattern is common, sometimes with dialyzer reuse and inadequate water treatment. A majority of patients decrease session frequency or discontinue the program due to financial constraint. (3) As convective therapies are gaining popularity in Europe, penetration in Asia is low and limited by costs. (4) In Asian countries, in particular in the South and South-East, hepatitis and tuberculosis infections in HD patients are higher than in the West and substantially increase mortality. (5) Progress has recently been made in countries like Thailand and Brunei to provide universal HD access to all patients in need. Nevertheless, well-trained personnel, reliable registries and better patient follow-up would improve outcomes in low-income Asian countries.

Impact of stepwise sodium and ultra filtration profiles and dialysis solution flow rate profile on dialysis adequacy.

BACKGROUND: Inadequate dialysis is one of the main causes of mortality of the patients undergoing hemodialysis. The methods that lead to improvement of dialysis adequacy in these patients are of great importance due to them causing an improvement of quality of life. As numerous factors can play a role in improvement of dialysis adequacy, the present study aimed to investigate the level of impact of stepwise sodium and ultra filtration profiles and dialysis solution flow rate profile on dialysis adequacy. MATERIALS AND METHODS: This is a cross-over clinical trial conducted on 32 patients selected from two hemodialysis centers in Isfahan in 2013. The patients were assigned to two identical groups through random allocation, and each patient in group 1 underwent hemodialysis for four routine dialysis sessions, four stepwise sodium and ultra filtration profile sessions, and four sessions by stepwise dialysis solution flow rate profile. The patients in group 2 underwent hemodialysis for four sessions of stepwise dialysate flow rate profile, four sessions of stepwise sodium and ultra filtration profiles, and four sessions of routine dialysis method. Dialysis adequacy was on line calculated by Kt/V ratio in each session, and was analyzed by repeated measure analysis of variance (ANOVA), least significant difference (LSD) post-hoc test, and independent t-test. RESULTS: Means of dialysis adequacies were 1.239 (0.25) in the routine method, 1.407 (0.26) in stepwise sodium and ultra filtration profiles, and 1.414 (0.26) in dialysis solution flow rate profile. There was a significant difference between the routine method and the other two profiles (P < 0.05), but the difference in dialysis adequacy means in the two profile methods was not significant (P > 0.05). Mean scores of dialysis adequacy in the three treatment methods in the two groups showed that the sequence of methods had no effect on treatment outcome (P > 0.05). CONCLUSIONS: Stepwise sodium and ultra filtration profiles and stepwise dialysis solution flow rate profile are suggested as they can increase dialysis adequacy compared to the routine method.

Nightly Home Hemodialysis: Fifteen Months of Experience in Lynchburg, Virginia.

What constitutes adequate dialysis has been debated in the nephrology literature over the past eight years. The mortality rate of patients on dialysis in the United States is about 20% per year. We believed that short and infrequent dialysis sessions contributed to poor outcomes. To improve the results, Lynchburg Nephrology started the nightly home hemodialysis (NHHD) program in September 1997. Ten patients were trained in the first 15 months of the program. Patients dialyzed 7 - 9 hours, 6 nights/week, using the Fresenius 2008H machine. A standard dialysis solution with 2.0 mEq/L potassium, calcium concentration of 3.0 - 3.5 mEq/L was used. Dialysis solution flow rates were 200 - 300 mL/min. Serum phosphate levels were maintained above 2.5 mg/dL by adding 0 - 45 mL Fleet's Phosphosoda to the bicarbonate bath. Patients had marked improvement in quality of life as measured with the SF-36. Blood pressure was better controlled with fewer medications. All phosphate binders were eliminated. Caloric intake and protein intake increased to normal levels as measured by three-day dietary histories pre-NHHD, and at 3, 6, and 12 months on NHHD. Epoetin alfa dosages were reduced by about 50%. Nightly home hemodialysis should be considered as a valuable modality option for end-stage renal disease patients; it is potentially superior to conventional thrice-weekly hemodialysis.

Clinical Significances of Carbamylated Hemoglobin in Patients with Chronic Renal Failure / 대한신장학회잡지

Carbamylated hemoglobin (CarHb) is formed by the reaction of hemoglobin with cyanate derived from the spontaneous dissociation of in vivo urea. Previous studies have shown that formation of CarHb depends upon both the severity and the duration of renal failure. To study the clinical significances of CarHb in Korean patients with chronic renal failure, we measured CarHb levels by high-performance liquid chromatography in 159 CRF patients and 46 normal controls. Patients with CRF had a higher CarHb concentration than normal controls (107.9+/-58.8 vs 35.1+/-14.2 microgramVH/gHb; P<0.001). In patients with CRF, nondialysis group had a higher value than dialysis group (129.8+/-77.9 vs 98.7+/-46.1 microgramVH/gHb; P<0.05). There were no siginificant difference in CarHb levels between hemodialysis (92.0+/-35.8microgramVH/gHb) and peritoneal dialysis (106.7+/-55.3microgramVH/gHb) groups. CarHb levels were not different between diabetic and nondiabetic patients in predialysis and hemodialysis groups. Although there was a significant difference in peritoneal dialysis group, the BUN levels were also lower in diabetic patients than nondiabetic patients. There were no correlation between CarHb and HbA1c percentage in patients with diabetes. CarHb levels were positively correlated with BUN (r=0.489; P<0.001) and creatinine (r=0.458; P<0.01) concentrations. There were negative correlations between CarHb and both Kt/V (r=-0.358; P<0.05) and URR (r=-0.415; P<0.05) in hemodialysis patients. In conclusion, CarHb may be a useful index of uremic control in patients with chronic renal failure, and are independent of the mode of dialysis and the presence of diabetes.