Ultrafiltration Rate Research Articles

Ultrafiltration rate adjusted to body weight and mortality in hemodialysis patients

Background and aimsMortality among hemodialysis patients remains high. An elevated ultrafiltration rate adjusted by weight (UFR/W) has been associated with hypotension and higher risk of death and/or cardiovascular events. MethodsWe evaluated the association between UFR/W and mortality in 215 hemodialysis patients. The mean follow-up was 28 ± 6.12 months. We collected patients’ baseline characteristics and mean UFR/W throughout the follow-up. ResultsMean UFR/W was 9.0 ± 2,4 and tertiles 7.1 y 10.1 mL/kg/h. We divided our population according to the percentage of sessions with UFR/W above the limits described in the literature associated with increased mortality (10.0 ml/kg/h and 13.0 mL/kg/h). Patients with higher UFR/W were younger, with higher interdialytic weight gain and weight reduction percentage but lower dry, pre and post dialysis weight. Throughout the follow-up, 46 (21.4%) patients died, the majority over 70 years old, diabetic or with cardiovascular disease. There were neither differences regarding mortality between groups nor differences in UFR/W among patients who died and those who did not. Contrary to previous studies, we did not find an association between UFR/W and mortality, maybe due to a higher prevalence in the use of cardiovascular protection drugs and lower UFR/W. ConclusionsThe highest UFR/W were observed in younger patients with lower weight and were not associated with an increased mortality.

Evaluation of dosing strategies and trough concentrations of vancomycin in patients undergoing continuous venovenous hemofiltration.

Recommendations regarding vancomycin dosing in critically ill patients on continuous venovenous hemofiltration (CVVH) are limited. The purpose of this study was to evaluate current dosing practices of pharmacists for patients treated with CVVH, develop guidelines for optimal dosing and monitoring of vancomycin to improve target trough attainment, and reduce pharmacist workload. A retrospective cohort study. was performed of critically ill adult patients from January 2015 to December 2018. Patients were included if they received vancomycin during CVVH for at least 48h. Patients with significant residual kidney function, defined as daily urine output >400ml or significant fluctuations (≥1000ml/h in a 24-h period) in their hemofiltration rates, were excluded. Interruptions in CVVH up to 6h/day were permitted. Dosing strategies with two dosing categories were defined: (1) dosing based on random serum levels (dosing by level, DBL) or (2) scheduled vancomycin dosing (SD). Academic medical center in Detroit, Michigan. Critically ill adult patients. During the study period, 942 patients were evaluated and 200 met inclusion criteria, for a total of 586 serum vancomycin levels. There were 141 patients with 443 random vancomycin serum levels in the DBL group and 59 patients with143 vancomycin trough levels in the SD group. Mean vancomycin trough levels were similar between groups (17.1±6 vs. 16.5±4mcg/ml) for the DBL and SD groups, respectively. For the primary end point of overall target trough achievement of 15-20mcg/ml, significantly more trough levels in the SD group were in the 15-20mcg/ml range compared with the DBL group, 50% vs. 38%; p<0.001, respectively. When target trough range was extended to 10-20mcg/ml, success rates were similar between groups (74% DBL vs. 82% SD, p=0.021). The number of interventions required by the pharmacist, including notes per day and orders per day, were reduced by approximately 50% when the SD strategy was utilized. Scheduled vancomycin dosing regimens of 15-22mg/kg every 12-24h were required to yield trough levels in the 15-20mcg/ml range. Target vancomycin trough achievement of 15-20mcg/ml occurred more frequently when vancomycin was scheduled at a dose of 15-22mg/kg every 12-24h based on ultrafiltration rate and may alleviate the time and cost associated with frequent vancomycin serum monitoring.

Sodium and ultrafiltration profiling in hemodialysis: A long-forgotten issue revisited.

Sodium and ultrafiltration profiling are method of dialysis in which dialysate sodium concentration and ultrafiltration rate are altered during the course of the dialysis session. Sodium and ultrafiltration profiling have been used, commonly simultaneously, to improve hemodynamic stability during hemodialysis. Sodium profiling is particularly effective in decreasing the incidence of intradialytic hypotension, while ultrafiltration profiling is suggested to decrease subclinical repeated end organ ischemia during dialysis. However, complications such as increased interdialytic weight gain and thirst due to sodium excess have prevented widespread use of sodium profiling. Evidence suggest that different sodium profiling techniques may lead to different clinical results, and preferring sodium balance neutral sodium profiling may mitigate adverse effects related to sodium overload. However, evidence is lacking on the long-term clinical outcomes of different sodium profiling methods. Optimal method of sodium profiling as well as the utility of sodium/ultrafiltration profiling in routine practice await further clinical investigation.

MO1007RELATIONSHIP BETWEEN DIALYSIS ADEQUACY, ULTRAFILTRATION RATE AND SURVIVAL IN YOUNG HEMODIALYSIS (HD) PATIENTS HAVING INITIATED CHRONIC HD IN CHILDHOOD*

Abstract Background and Aims Hemodialysis (HD) adequacy is currently assessed based on weight-normalized small solute clearance (spKt/V), with same targets in both adult and pediatric patients on chronic thrice weekly hemodialysis, despite lack of pediatric studies to support this. It has been hypothesised that pediatric patients of small size may require higher spKt/V targets, due to higher ratio of body surface area (BSA) to body weight and/or greater post-dialysis urea rebound. Ultrafiltration rates (UFR) &amp;gt;10-13 mL/kg/h, associated with increased mortality in adults, are furthermore routinely exceeded in pediatric patients with uncertain consequences. We aimed to characterize how different delivered HD adequacy metrics and UFR are associated with survival in a large cohort of patients who started HD in childhood. Method Retrospective analysis on a cohort of patients &amp;lt;30y on chronic HD since childhood (&amp;lt;19y), having received thrice-weekly HD 2004-2016 in outpatient DaVita dialysis centers. Mean delivered dialysis dose (spKt/V) and alternative measures of HD adequacy and fluid balance, including eKt/V, body-surface normalized Kt (Kt/BSA) and ultrafiltration rate (UFR), were investigated as predictors of survival in a Weibull regression model. Results A total of 1780 patients were included (age at initiation of HD: 0-12y: n=321, &amp;gt;12-18y: n=1459), with median spKtV=1.55, eKt/V=1.31, Kt/BSA=31.2 L/m2 and UFR=10.6 mL/kg/h. Kt/BSA was a better predictor of survival than spKt/V or eKt/V (P&amp;lt;0.001 versus P=0.002, respectively). UFR was associated with survival (P&amp;lt;0.001), with increased mortality &amp;lt;10/&amp;gt;18 mL/kg/h. Associations remained significant after adjusting for age, ethnicity, and etiology of kidney disease. Conclusion We found that targeting Kt/BSA&amp;gt;30 L/m2 in children and young adults on maintenance HD is associated with improved long-term outcomes, corresponding to spKt/V&amp;gt;1.4 (&amp;gt;12 years) and &amp;gt;1.6 (&amp;lt;12 years), respectively. Relatively high UFR of 10-18 ml/kg/h appears to be risk-free in this HD population.

MO834LOWER POST DIALYSIS POTASSIUM AND HIGHER ULTRAFILTRATION RATE ARE INDEPENDENT PREDICTORS OF ALL-CAUSE MORTALITY IN DIALYSIS PATIENTS

Abstract Background and Aims Dialysis is a life-saving procedure for the end-stage kidney disease, but mortality in this category of patients is still high. The survival of these patients is much lower compared to the general population. Factors affecting this survival has been studied for years and still continue to be an important part of current studies. While ultrafiltration rate is known to be associated with mortality in prevalent dialysis patients an important predictor of survival is the control of potassium profile. The aim of our study was to assess the hemodynamic and biochemical data, and to identify any significant association between post-dialysis potassium and all-cause mortality. Method This is a prospective study of 308 patients on maintenance dialysis, followed for seven years, ending 2019. All patients are dialysis dependent for ESKD and getting treatment in a single-center. Hypokalemia was defined as a serum potassium level &amp;lt; 3.5 mEq/L and high ultrafiltration rate (UFR) &amp;gt; 13 ml/kg/h. Other hemodynamic and metabolic data were also evaluated The survival rate was analysed by Kaplan-Meier curves and Cox regression analysis. Results A total of 308 patients were enrolled in this study. Mean age was 52 ± 15.6 years; 62.3% of pts were male; BMI 24.7±4.2. Of these, 55 patients (17.9%) died during the follow-up period. Our data showed the presence left ventricular hypertrophy (p=0.010), peripheral artery disease (p&amp;lt;0.0001), diastolic disfunction (p&amp;lt;0.01) and ultrafiltration rate during dialysis &amp;gt;13ml/kg/h (p=0.002) were the most important predictors of mortality. Metabolic abnormalities, low albumin (p&amp;lt;0.0005), hyperphosphatemia (p=0.011), post-dialysis potassium (p=0.037) were significantly associated with higher mortality. Logistic regression analysis of the metabolic data identified post-dialysis potassium (OR 0.242, 95% CI 0.074 – 0.793, p=0.019), and logistic regression analysis of the hemodynamic data identified ultrafiltration ratio (OR 0.149, CI 0.033 – 0.673, p=0.013) as independent predictors of all-cause mortality. Conclusion Lower post dialysis potassium levels and higher ultrafiltration rate are independently associated with higher all-cause and CV mortality in prevalent hemodialysis patients. Therefore the potassium profile and the UFR of the dialysis patients needs close monitoring and optimal control. The individualization of the dialysis prescription is recommended for each patient and it has an important role in preventing the occurrence of complication with immediate and long term effects. Management of dialysis patients should focus especially on reducing the risk of hypokalemia, not only that of hyperkalemia.

MO730THORACIC BIOIMPEDANCE AS AN INNOVATIVE TOOL TO DETECT CHANGES IN BLOOD PRESSURE DURING HEMODIALYSIS

Abstract Background and Aims Blood pressure (BP) variability is an important cardiovascular risk factor that contributes to the high burden of cardiovascular mortality in hemodialysis (HD) patients. Ultrafiltration rate (UFR) and plasma refill rate modify the extracellular volume (ECV), which is a major determinant of the systolic BP. Segmental bioimpedance of the thoracic region addresses the central volume compartment of the body. We hypothesize that changes in bioimpedance reflect changes in BP and that thoracic measurements are more accurately in detecting intradialytic BP changes compared to whole body bioimpedance. Method During two consecutive short-term interval HD sessions, thoracic bioimpedance signal was registered continuously from predialysis until the end of the session. Corresponding BP, whole body bioimpedance and ultrafiltration volume (UFV) after the start and at the end of dialysis was registered. After outlier detection, valid raw bioimpedance data [Ohm] at 8 and 160 kHz for thoracic measurements, and 5 and 200 kHz for whole body measurements, were taken into further analysis. Dialysis sessions were divided into 3 groups according to the development of the systolic BP: a drop ≥ than 20 mmHg was defined as a hypotensive session, an increase ≥ 10 mmHg was considered as a hypertensive session. Pearson correlation analysis was applied (r, p-value) to the relative data, calculated as a percentage from the start value. Results From 2 dialysis centres, a total of 46 HD patients were enrolled in the study (65.2% male, mean age 71 ± 12.6 years, mean dialysis vintage 4 ± 3.9 years), which resulted in 89 dialysis sessions to analyse. Mean systolic BP after start of dialysis was 133.2 ± 20.7 mmHg and mean UF volume was 1817.5 ± 801.5 mL. 23 sessions showed a hypotensive gradient from the start till the end of dialysis, and 13 sessions progressed with an increase of more than 10 mmHg. When the 8 kHz curve was plotted according to the 3 BP groups, a more plane increase in thoracic bioimpedance signal was observed in the group with a normal tension course (Figure 1). There was a significant relationship between UFR and changes in relative bioimpedance data, as well as thoracic (r = .49 at 8 kHz, r = .46 at 160 kHz, all ps &amp;lt; .001), as whole body bioimpedance (r = .58 at 5 kHz, r = .52 at 200 kHz, all ps &amp;lt; .001). UFV correlated with changes in systolic BP (r = -.31, p &amp;lt; .01). Both bioimpedance techniques correlated with each other (r = .38, p = .001 for low frequencies; r = .29, p &amp;lt; .01 for high frequencies). Where the relative thoracic bioimpedance signal correlated with changes in systolic BP (r = -.35 at 8kHz, -.32 at 160 kHz, all ps &amp;lt; .01) (Figure 2), whole body did not. Conclusion Thoracic bioimpedance is associated with intradialytic BP changes, whereas whole body bioimpedance is not. Thoracic bioimpedance has the potential to function as an important diagnostic and predictive tool in BP variability during HD.

MO418CONTINUOUS RENAL REPLACEMENT THERAPY WITH REGIONAL CITRATE ANTICOAGULATION VERSUS NON-ANTICOAGULATION REGIME IN CRITICALLY ILL PATIENTS WITH ACUTE KIDNEY INJURY AND A HIGH RISK OF BLEEDING

Abstract Background and Aims Critically ill patients with acute renal impairment (AKI) with a high risk of bleeding require treatment with one of the methods of continuous renal replacement (CRRT) with regional citrate anticoagulation (RCA) or without anticoagulation (NA). The aim of the study was to compare CRRT with RCA using calcium with CRRT in NA regimen. Method A clinical trial included 55 surgical and non-surgical patients with acute kidney injury and an episode of acute kidney injury in chronic kidney disease who were admitted to the Intensive Care Unit (ICU) during 2020. The patients were divided into two groups, RCA- CRRT with 39 and NA-CRRT with 16 patients. Demographic, clinical and lab data before and after CRRT, treatment parameters CRRT and outcomes were analyzed. Results RCA vs NA group did not differ significantly by gender (small, 71.79% vs 56.25%, p = 0.106) and age (56.53 ± 17.55 vs 45.75 ± 13.3, p = 0.220). The NA group had a significantly higher prevalence of liver disease as a reason for the ICU admission when compared to the other group (12.5% vs 0.00%, p = 0.024). The RCA group before CRRT had significantly higher mean values of CRP (173.68 ± 122.06 vs 86.33 ± 51.05, p = 0.01) and significantly lower mean values of total bilirubin (16.78 ± 4.31 vs 40.02 ± 9.22, p = 0.005) and creatinine (463.97 ± 36.24 vs 486.0 ± 36.25, p = 0.001), while after CRRT it had significantly higher average values of total calcium (2.12 ± 0.016 vs 2.11 ± 0.017, p = 0.023) and lower average values of pH (7.29 ± 0.02 vs 7.32 ± 0.015, p = 0.040) and creatinine (463.97 ± 36.24 vs 486.0 ± 36.25, p = 0.001) in relation to the NA group. No significant difference was found in relation to invasive mechanical ventilation, vasopressors therapy, SAPS II score, oliguria / anuria, recovery of renal function, the length of hospital stay and mortality (p&amp;gt; 0.05) (Table 1). Compared to treatment parameters, the RCA group had a significantly lower number of procedures (4.33 ± 2.80 vs 5.81 ± 1.28, p = 0.027) and ultrafiltration rate (2.79 ± 0.19 vs 3.14 ± 0.33, p = 0.015) and significantly longer hemofilter lifespan compared to NA group (24.64 ± 0.48 vs 18.10 ± 0.58, p = 0.000). Although the prevalence of bleeding was higher in the NA group, no significant difference was found between the groups (37.5% vs 28.20%, p = 0.498), as well as in the infusion of red blood cell (33.3% vs 37.5%, p = 0.768), fresh frozen plasma (28.2% vs 50%, p = 0.742) and platelets (35.89 vs 31.25, p = 0.123). The overall citrate accumulation (CA&amp;gt; 2.25) rate was 5.12% in the RCA group (Table 2). The Kaplan-Meier survival analysis using the log-rank test (Mantel-Cox test) for comparing the hemofilter lifespan between RCA and NA regime found a significant difference in survival between the groups (χ2 = 3,789, p = 0,049) (Figure 1). Multiple regression model for testing risk factors SAPS II score, Oxiris membrane, UF, lactate, hemoglobin concentration, platelet count, Activated Partial Thromboplastin Time and Prothrombin Time on hemofilter survival has shown a significant linear relationship without statistical significance in both RCA groups (R=0.544 ; F=1.575) and NA (R=0.757; F=1.171) (Table 3). Conclusion RCA-CRRT did not show a significant difference in the prevalence of bleeding compared to NA-CRRT in the patients with a high risk of bleeding, but the survival rate of hemofilters was significantly longer in RCA-CRRT, which suggested the need for further research.

Fatigue in hemodialysis patients: A single-center cross-sectional study

Fatigue is a highly prevalent condition among people affected by chronic disease, with consequent poor health-related quality of life and lower survival rates. Fatigue is one of the most common and debilitating symptoms also experienced by hemodialysis (HD) patients after HD sessions, and given the non-specific manifestations and its invisible nature, it is under-recognized and under-treated by healthcare professionals. The complexity of fatigue's pathogenesis and the lack of measurement tools make the development of nursing interventions and practices specifically targeted at its recognition and therapy difficult. We aimed to investigate the prevalence and severity of fatigue, identify predictor variables in HD patients, and promote healthcare professionals' awareness and recognition of fatigue. A single-center, cross-sectional study was conducted among 140 patients treated at the HD unit between August 2019 and March 2020 at the Nephrology, Dialysis, and Transplantation Unit of Padova University Hospital. We assessed patient's fatigue by Chalder's Fatigue Questionnaire, pain by Numeric Rating Scale and activities of daily living by Barthel Index. Demographic and clinical characteristics were taken from medical records. The findings of this study indicate that age, dialysis vintage, inter-dialysis weight gain, and ultra-filtration rate are proportionally related to reported levels of fatigue. Hemoglobin, iron, ferritin, and number of sleep hours before HD session present a significant inverse correlation to fatigue. The complexity of fatigue's pathogenesis makes a better understanding of this phenomenon difficult, nevertheless, healthcare professionals should develop interventions and practices targeted at its identification and management.

Electrocardiographic parameters of left ventricular hypertrophy and prediction of mortality in hemodialysis patients

BackgroundIn hemodialysis patients, left ventricular hypertrophy (LVH) contributes to high cardiovascular mortality. We examined cardiovascular mortality prediction by the recently proposed Peguero-Lo Presti voltage since it identifies more patients with electrocardiographic (ECG) LVH than Cornell or Sokolow-Lyon voltages.MethodsA total of 308 patients on hemodialysis underwent 24 h ECG recordings. LVH parameters were measured before and after dialysis. The primary endpoint of cardiovascular mortality was recorded during a median 3-year follow up. Risk prediction was assessed by Cox regression, both unadjusted and adjusted for the Charlson Comorbidity Index and the Cardiovascular Mortality Risk Score.ResultsThe Peguero-Lo Presti voltage identified with 21% the most patients with positive LVH criteria. All voltages significantly increased during dialysis. Factors such as ultrafiltration rate, Kt/V, body mass index, sex, and phosphate were the most relevant for these changes. During follow-up, 26 cardiovascular deaths occurred. Post-dialysis Peguero-Lo Presti cut-off as well as the Peguero-Lo Presti and Cornell voltages were independently associated with cardiovascular mortality in unadjusted and adjusted analysis. The Sokolow-Lyon voltage was not significantly associated with mortality. An optimal cut-off for the prediction of cardiovascular mortality was estimated at 1.38 mV for the Peguero-Lo Presti.ConclusionsThe post-dialysis Peguero-Lo Presti cut-off as well as the Peguero-Lo Presti and Cornell voltages allowed independent risk prediction of cardiovascular mortality in hemodialysis patients. Measuring the ECG LVH parameters after dialysis might allow a standardized interpretation as dialysis-specific factors influence the voltages.Graphical abstract

Atherosclerosis-calcification score and predictors of intra-dialytic hypotension.

Intra-dialytic hypotension episodes (ID-Hypos) cause significant reduction of dialysis efficiency and increased cardiovascular morbimortality. Atherosclerosis and vascular calcification are two closely inter-related processes that occur prematurely and progress aggressively in maintenance hemodialysis (MHD) patients. To study the predictors of ID-Hypos, particularly a novel combined atherosclerosis-calcification score (CACS) (0 to 6) obtained by adding the atherosclerosis score (AS) to a modified abdominal aortic calcification score (AACS), each ranging 0 to 3. In 60 adult MHD patients, AS was derived from ankle-brachial index and carotid ultrasound. AACS was modified from Kauppila score applied on lateral abdominal plain radiographs. The number of sessions complicated by ≥ 1 ID-Hypos over 14 weeks was recorded and correlated with CACS, ultrafiltration rate (UFR), and other hemodynamic and laboratory parameters. Patients developed a median of 10.5 ID-Hypos (IQR 5.75-14). The number of ID-Hypos had a statistically significant positive correlation with CACS (r = 0.291, p = 0.024), but not with its individual components. AACS had a statistically significant positive correlation with s. phosphorus and calcium-phosphorus product. On multivariate analysis, the most significant independent predictors of ID-Hypos were high UFR, high CACS, and low hemoglobin. Serum C-reactive protein had a positive correlation with ID-Hypos that was lost in the adjusted models. High UFR, CACS, and anemia are significant predictors of ID-Hypos. CACS may help in quantifying vascular pathology and characterizing MHD patients at highest risk for ID-Hypos, those who would be prioritized for potential preventive measures like biocompatible membranes or hemodiafiltration. A background of chronic inflammation may underlie and link patient-related ID-Hypos risk factors.

Nutritional status and volume control in adolescents on chronic hemodialysis.

Pediatric patients on maintenance hemodialysis (HD) are at risk of both malnutrition and fluid overload. This pilot study aimed to assess correlates of normalized protein catabolic rate (nPCR) in adolescents on chronic HD, in particular fluid status markers. All patients aged 10-18 years on chronic HD in our center between 2017 and 2019 were enrolled. For each patient, mean nPCR was calculated and correlations with the following parameters investigated: dry body weight change in subsequent 3 months in kg (∆BW) and percentage of BW (∆BW%), change in body mass index (∆BMI), preHD systolic and diastolic blood pressure (SBP, DBP), residual urine output, biochemistry, and blood volume monitoring-derived first hour refill index (RI), calculated as ratio between ultrafiltration rate and reduction in relative blood volume in first hour of dialysis. Seventy-nine nPCR determinations were collected in 23 patients, median age 14.8 years. nPCR significantly correlated with ∆BW, ∆BW%, ∆BMI, spKT/V, and preHD serum creatinine, and negatively correlated with age, DBP SDS (r=-0.466, p=0.025) and RI (r=-0.435, p=0.043). RI was significantly higher in patients with nPCR <1 than those with nPCR above this threshold: 3.2 (1.9-4.7) vs. 1.4 (0.7-1.8) ml/kg/h/% (p=0.021). At multivariable analysis, nPCR remained positively correlated with creatinine and spKt/V, and inversely correlated with RI. nPCR is a significant predictor of weight change in adolescents on maintenance HD, and seems associated with creatinine and dialysis adequacy. Inverse correlation with RI suggests possible associations between malnutrition and fluid overload, but larger prospective studies are needed to confirm this. A higher resolution version of the Graphical abstract is available as Supplementary information.

A predictive model of nanoparticle capture on ultrathin nanoporous membranes

Beyond their use as separation tools, nanoporous membranes can be used for the capture and analysis of biological nanoparticles such as virus or small extracellular vesicles (sEVs). While the challenges of imaging sub-optical particles can be addressed with high resolution imaging techniques, separation challenges remain. We have recently reported on a method of capturing and isolating sEVs, including diagnostically valuable exosomes, in the pores of ultrathin (100 nm thick) nanoporous silicon nitride (NPN) membranes in a microfluidic flow scheme we termed tangential flow for analyte capture (TFAC). Here we present static analytical and dynamic computational models of nanoparticle capture on NPN and compare them to a range of experiments using 60 nm gold nanoparticles (AuNPs) as surrogates for biological nanoparticles. In the presence of 1 mg/mL bovine serum albumin to prevent the formation of gold nanoparticle aggregates, we find that the dynamic model is highly predictive of particle capture over a range of practical flow conditions (~ 10% error at low ultrafiltration rates, ~ 1% error at high ultrafiltration rates). Despite the small size of nanoparticles, we find that convective transport dominates diffusive transport during capture (Peclet number > 100), enabling the simple rule-of-thumb that the fraction of nanoparticles captured from solution roughly equals the fraction of the input sample that is ultrafiltered (<15% maximum error). Our work demonstrates the utility of ultrathin membranes in the capture and quantification of nanoparticles in a microfluidic filtration device and provides a needed foundation for the design of forthcoming systems that capture and characterize diagnostically relevant nanoparticles and biomarkers.

Predictors of kidney function recovery among incident ESRD patients

BackgroundESRD is considered an irreversible loss of renal function, yet some patients will recover kidney function sufficiently to come off dialysis. Potentially modifiable predictors of kidney recovery, such as dialysis prescription, have not been fully examined.MethodsRetrospective cohort study using United States Renal Data System (USRDS) data to identify incident hemodialysis (HD) patients between 2012 and 2016, the first 4 years for which dialysis treatment data is available. The primary outcome was kidney recovery within 1 year of ESRD and HD initiation, defined by a specific recovery code and survival off dialysis for at least 30 days. Patient and treatment characteristics were compared between those that recovered versus those that remained dialysis-dependent. A time-dependent survival model was used to identify independent predictors of kidney recovery.ResultsDuring the study period, there were 372,387 incident HD patients with available data, among whom 16,930 (4.5%) recovered to dialysis-independence. Compared to non-recovery, a higher proportion of patients with kidney recovery were of white race, and non-Hispanic ethnicity. Both groups had a similar age distribution. Patients with an acute kidney injury diagnosis as primary cause of ESRD were most likely to recover, but the most common ESRD diagnosis among recovering patients was type 2 diabetes (29.8% of recovery cases). Higher eGFR and lower albumin at ESRD initiation were associated with increased likelihood of recovery. When examining HD ultrafiltration rate (UFR), each quintile above the first quintile was associated with a progressively lower likelihood of recovery (HR 0.45, 95% CI 0.43–0.48 for highest versus lowest quintile, p < 0.001).ConclusionsWe identified non-modifiable and potentially modifiable factors associated with kidney recovery which may assist clinicians in counseling and monitoring incident ESRD patients with a greater chance to gain dialysis-independence. Clinical trials are warranted to examine the impact of dialysis prescription on subsequent kidney function recovery.

Monitoring skin blood flow to rapidly identify alterations in tissue perfusion during fluid removal using continuous veno-venous hemofiltration in patients with circulatory shock

BackgroundContinuous veno-venous hemofiltration (CVVH) can be used to reduce fluid overload and tissue edema, but excessive fluid removal may impair tissue perfusion. Skin blood flow (SBF) alters rapidly in shock, so its measurement may be useful to help monitor tissue perfusion.MethodsIn a prospective, observational study in a 35-bed department of intensive care, all patients with shock who required fluid removal with CVVH were considered for inclusion. SBF was measured on the index finger using skin laser Doppler (Periflux 5000, Perimed, Järfälla, Sweden) for 3 min at baseline (before starting fluid removal, T0), and 1, 3 and 6 h after starting fluid removal. The same fluid removal rate was maintained throughout the study period. Patients were grouped according to absence (Group A) or presence (Group B) of altered tissue perfusion, defined as a 10% increase in blood lactate from T0 to T6 with the T6 lactate ≥ 1.5 mmol/l. Receiver operating characteristic curves were constructed and areas under the curve (AUROC) calculated to identify variables predictive of altered tissue perfusion. Data are reported as medians [25th–75th percentiles].ResultsWe studied 42 patients (31 septic shock, 11 cardiogenic shock); median SOFA score at inclusion was 9 [8–12]. At T0, there were no significant differences in hemodynamic variables, norepinephrine dose, lactate concentration, ScvO2 or ultrafiltration rate between groups A and B. Cardiac index and MAP did not change over time, but SBF decreased in both groups (p < 0.05) throughout the study period. The baseline SBF was lower (58[35–118] vs 119[57–178] perfusion units [PU], p = 0.03) and the decrease in SBF from T0 to T1 (ΔSBF%) higher (53[39–63] vs 21[12–24]%, p = 0.01) in group B than in group A. Baseline SBF and ΔSBF% predicted altered tissue perfusion with AUROCs of 0.83 and 0.96, respectively, with cut-offs for SBF of ≤ 57 PU (sensitivity 78%, specificity 87%) and ∆SBF% of ≥ 45% (sensitivity 92%, specificity 99%).ConclusionBaseline SBF and its early reduction after initiation of fluid removal using CVVH can predict worsened tissue perfusion, reflected by an increase in blood lactate levels.

Serum sodium variation is a major determinant of peridialytic blood pressure trends in haemodialysis outpatients

Intradialytic hypotension (IDH) and peridialytic blood pressure (BP) trends are associated with morbidity and mortality in haemodialysis (HD) patients. We aimed to characterise the respective influence of volume status and small solutes variation on peridialytic systolic BP (SBP) trends during HD. We retrospectively analysed the relative peridialytic SBP decrease in 647 prevalent outpatients attending for their mid-week session with corresponding pre- and post-HD bioelectrical impedance analysis. Mean SBP decreased by 10.5 ± 23.6 mmHg. Factors positively associated with the relative decrease in SBP were: serum sodium (Na) decrease, body mass index, serum albumin, dialysis vintage, ultrafiltration rate and urea Kt/V (p < 0.05 for all). Antihypertensive medications and higher dialysate calcium were negatively associated with the relative decrease in SBP (p < 0.05 for both). Age had a quadratic relationship with SBP trends (p < 0.05). Pre-HD volume status measured by extracellular to total body water ratio was not associated with SBP variation (p = 0.216). Peridialytic SBP trends represent a continuum with serum Na variation being a major determinant while volume status has negligible influence. Middle-aged and overweight patients are particularly prone to SBP decline. Tailoring Na and calcium dialysate concentrations could influence haemodynamic stability during HD and improve patient experience and outcomes.

Short-term Individualized Dialysate Cooling in Chronic Hemodialysis: Therapeutic benefits for Patients and A favorite choice for Nephrologists

Background: Intra-dialytic hypotension (IDH) and pruritus are frequent and distressing complications during hemodialysis; moreover, they are associated with adverse outcomes. The aim of the work: The current work aimed to investigate the effect of applying individualized cool dialysate (ICD) on IDH, dialysis adequacy, pruritus and its acceptance by both patient and nephrologists. Patients and Methods: This is a non-randomized single center study that was conducted at Al-Azher nephrology and dialysis unit. The study was carried out over a period of fvie weeks. Core body temperature (CBT) and dialysis adequacy (by Kt/v) were measured. Patients who fulfilled the inclusion and exclusion criteria underwent hemodialysis for six consecutive sessions at dialysate temperature of 37°C, followed by another six consecutive sessions at ICD temperature (0.5 oC below CBT). Blood pressure (BP) measurements, episodes of hypotension, pruritus score, patients and nephrologist questionnaire were collected during both standard and cool phases. Results: The study included 50 patients, the mean age 51.10±11.57 years, and males constituted 64% . The implementation of ICD has been associated with a significant reduction in IDH episodes (p <0.001). The lowest intra-dialytic and post-dialytic BP measurements were statistically higher during cool phase. There was a significant reduction in pruritus VAS score during cool phase (p <0.001), whereas Kt/v and ultrafiltration rate did not statistically differ between both phases. ICD was well tolerated by patients; although 60% of them experienced cold sensation that warranted no intervention. Nephrologists (n=20) trusted in cool dialysate as an effective intervention for IDH management. However, a proportion of them (60%) had a concern about patient tolerability. Conclusion: ICD is a well-tolerated intervention that is universally applied without additional cost. It improves hemodynamic instability and pruritus during hemodialysis treatment without negative impact on dialysis adequacy. It is accepted by nephrologists as an effective tool in stabilizing hemodynamic instability during dialysis treatment.

The effects of pre‐dialysis blood pressure targets on prognosis and health‐related quality of life in haemodialysis patients

The aim of the study is to investigate the effects of pre-dialysis blood pressure targets on health-related quality of life and prognosis and to determine the optimal target for pre-dialysis blood pressure in haemodialysis patients. A total of 58 haemodialysis patients undergoing dialysis for more than 3months were enrolled in the study from 1 January 2018 to 31 December 2018. The subjects were divided into two groups according to their pre-dialysis blood pressure: a standard target group (pre-dialysis systolic blood pressure of 110-140mmHg) and a relaxed target group (pre-dialysis systolic blood pressure of 155-165mmHg). The Quality Metrics SF-36 survey instrument was used to assess health-related quality of life in the study participants. In addition, general clinical data and biochemical indicators including heart rate, respiration rate, blood pressure and ultrafiltration volume and rate during dialysis were observed and recorded. Patients were followed-up for 12months, and prognostic data were recorded. Death was regarded as the endpoint. Scores on the SF-36 in the standard target group were significantly higher than those in the relaxed target group, with the exception of the role-emotional (RE) and mental health (MH) dimensions. At the end of the study, the number of mortality events in the relaxed target group was higher than in the standard target group. There were no other significant differences between the two groups. The scores from the health-related quality of life survey were higher in standard target group, but no differences in mortality risk between the two groups were observed.

ARTERIAL STIFFNESS CIRCADIAN PATTERN AND CARDIOVASCULAR MORTALITY IN HEMODIALYZED PATIENTS

Objective: Our aim was to analyze association of circadian pattern of 48-hours pulse wave velocity (PWV) and augmentation index (AIx) with cardiovascular (CV) mortality in patients undergoing chronic hemodialysis (HD). Design and method: 85 patients (mean age, 48m; 37w) were followed-up until for 36-months or till the time of death. Blood pressure (BP) (Omron M6), 48-h PWV and AIx (Arteriograph) and 24-h ABPM (SpaceLab 90207)-both after mid-week dialysis session were measured in all patients. PWV dippers = night-time PWV drop &gt; 0.5 m/s; PWV risers = night-time PWV rise &gt; 0.5 m/s compared to the day-time period. Aix dippers= night-time Aix drop &gt; 10%; Aix risers= night-time Aix rise &gt; 10% compared to day-time period. Results: After 36 months of follow-up, CV mortality was 49.4% (men 57.1%, women 42.9%). Deceased patients were older when enrolled and when had started with dialysis (both p &lt; 0.001). There were no differences in prevalence of hypertension (100% vs. 95.3%), diabetes (23.8% vs. 11.6%) and number of hypertensive drugs (3.51 vs. 3.23) between two groups (all p &gt; 0.05). Deceased patients had significantly longer duration of hypertension (p &lt; 0.01) as well as significantly higher proportion of AIx and PWV risers and higher nocturnal AIx levels than survived patients. On the non-dialysis day both nocturnal AIx and PWV levels were higher in deceased group with significantly more AIx and PWV dippers when compared to survivors. PWV risers were significantly older when enrolled and when started with dialysis and had significantly higher ultrafiltration rates than PWV non-risers and survived significantly shorter. In the linear regression model survival was negatively associated with age, duration of hypertension, ultrafiltration but the strongest association was with AIx and PWV risers on the non-dialysis day. On logistic regression only PWV rising pattern on non-dialysis day had increased HR of 1.78 [CI 1.60, 1.96] for CV mortality. Conclusions: Non-rising patterns of PWV and AIx on non-dialysis days were significantly associated with CV mortality in patients undergoing chronic HD. Our data confirmed importance of 48-hour measurements of PWV and Aix in prediction of CV mortality.

High Ultrafiltration Increasing Intradialytic Blood Pressure on Hemodialysis Patients

The increase in blood pressure when the patient is undergoing hemodialysis is experienced by patients with intradialytic hypertension. This condition can be very dangerous for the patient, must be prevented and needs to be controlled. Prevention can be done by controlling variables that can affect intradialytic blood pressure, including ultrafiltration during hemodialysis. This study aims to analyze the relationship between ultrafiltration (ultrafiltration goal, ultrafiltration rate) and intradialytic blood pressure. This research was a descriptive-analytic study with a cross-sectional design, with 112 samples at two centres of dialysis in Semarang. Data were analyzed using the Spearman Rho. The finding obtained showed that ultrafiltration goal (UFG) and ultrafiltration rate (UFR) correlated with intradialytic blood pressure (systolic, diastolic and mean arterial pressure). The magnitude of UFG an associated with increase in intradialytic systolic (p=0,024; r=0,213), increase in intradialytic diastolic (p=0,007; r=0,252) and increase in mean arterial pressure (p=0,016; r=0,227). High UFR is associated with with increase in intradialytic systolic (p=0,037; r=0,211), increase in intradialytic diastolic (p=0,001; r=0,320) and increase in mean arterial pressure (p=0,034; r=0,200). Determination of ultrafiltration during hemodialysis must be done carefully and precisely to prevent an increase in intradialytic blood pressure.

Effective glutamate clearance from the systemic circulation by hemodialysis: Potential relevance for cerebral ischemia management.

High glutamate levels after head trauma or cerebral ischemia have neurotoxic effects. The objective of the present study was to evaluate the efficacy of hemodialysis to remove glutamate from the blood and to assess the behavior of this small molecule. Ten patients with end-renal disease on hemodialysis were included in the study. Glutamate clearance was evaluated within the first hour of hemodialysis on a midweek dialysis day on five patients who underwent low flux hemodialysis, whereas the other five patients underwent highly efficient hemodialysis (high flux hemodialysis on one day and online hemodiafiltration on another day). Glutamate clearance with hemodialysis was very effective and did not show any differences between the techniques (low flux: 214 [55], high flux: 204 [37], online hemodiafiltration: 202 [16], median (interquartile range), P=.7). Glutamate clearance was almost equivalent to vascular access plasma flow and it was not affected by dialyzer permeability or ultrafiltration rate. After a hemodialysis session, a significant decrease in glutamate blood level was observed (prehemodialysis: 59.7 [36.1], posthemodialysis 37.0 [49.2], P=.005). Dialysis performed under fasting condition showed higher glutamate reduction rate (60%) than that under feeding condition (20%). Hemodialysis may be an effective method to reduce glutamate blood levels, and the molecule clearance does not differ between the different techniques used. Considering previous results in experimental models, hemodialysis without hemodynamic stress, could be considered for reducing glutamate neurotoxic effects in acute ischemic strokes of patients in chronic hemodialysis programs.