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Neurological and vascular complications associated with creation of arteriovenous access need to be recognized promptly to deliver appropriate interventions for relief of symptoms and avoid loss of function of the involved extremity. We present here a 55-year-old female with end-stage renal disease on hemodialysis secondary to diabetic nephropathy who had a surgical creation of first stage of the brachial artery-basilic vein fistula in the left arm. She subsequently developed pain and weakness of the left arm which was diagnosed as median and ulnar nerve entrapment. She was treated with surgical nerve release and neurolysis and her symptoms improved.

Background: Matrix Gla Protein (MGP) is a potent inhibitor of ectopic calcification and modulates bone morphogenesis. Little is known about MGP expression or function in kidney. Methods: We investigated renal MGP expression in Sprague-Dawley rats after 5/6 nephrectomy (5/6 Nx) and in human kidney biopsies in the Nephrotic Syndrome Study Network (NEPTUNE) cohort. We analyzed associations between glomerular (n = 182) and tubulointerstitial (TI) (n = 219) MGP mRNA levels and the disease activity/histologic features in NEPTUNE patients. Additionally, uncarboxylated and carboxylated MGP (ucMGP and cMGP, respectively) were localized by immunohistochemistry and quantitated in kidney tissues of patients at different stages of CKD (n = 18). Results: Renal MGP expression was increased in rats after 5/6 Nx. In NEPTUNE data, baseline estimated glomerular filtration rate (eGFR) negatively correlated with glomerular and TI MGP expression (p < 0.001). TI MGP expression strongly correlated with interstitial fibrosis, tubular atrophy, acute tubular injury, and interstitial inflammation, independent of eGFR. Kaplan-Meier analysis and multivariable Cox regression showed that higher levels of TI MGP expression were associated with an increased risk for the composite of 40% decline in eGFR and end-stage renal disease (ESRD) (HR, 3.31; 95% CI, 1.31 to 6.32; p = 0.02). Glomerular and tubulointerstitial cells demonstrated nuclear and cytoplasmic cMGP and ucMGP staining, and eGFR inversely correlated with quantified glomerular cMGP staining (p < 0.05). Conclusions: Our data demonstrate that renal MGP expression is increased in human and experimental CKD, and is associated with renal outcome. Additional studies are needed to determine its mechanism of action.

Objective As vascular surgeons strive to meet the Fistula First Initiative, some authors have observed a decrease in arteriovenous fistula (AVF) maturation rates in association with an increase in AVF creation. In May 2012, we adopted a practice change in an attempt to maintain the same high level of AVF creation while leading to a decrease in fistula failures. Methods A retrospective study was conducted of all dialysis access procedures performed by a single vascular surgeon before (period 1; before May 1, 2012) and after (period 2; after May 1, 2012) the change in practice pattern. The adopted change included favoring the brachiocephalic location unless the patient was an ideal anatomic candidate for a radiocephalic AVF, creating a larger and standardized arteriotomy, and using a large venous footplate whenever possible. The main outcome measure was primary functional patency at 1 year. Secondary outcome measures included primary patency at 1 year, time to maturation, type of fistula created, steal syndrome, and tunneled hemodialysis catheter infections. Results Of 213 vascular access procedures performed, 191 (90%) were AVFs. There was no difference in use of AVFs between period 1 (93% AVFs) and period 2 (88% AVFs; P = .2). Use of brachiocephalic AVFs increased from 38% in period 1 to 56% in period 2 ( P = .01), with a corresponding trend toward a decrease in radiocephalic AVFs in period 2 (36% in period 1 to 27% in period 2; P = .2). Primary functional patency at 1 year was 47% in period 1 and 63% in period 2 ( P = .03). Primary patency at 1 year was 51% in period 1 and 70% in period 2 ( P = .001). Time to reach functional maturation was decreased in period 2 (median, 76 vs 82.5 days; P = .046). There was no difference in steal syndrome ( P = 1.0), and the incidence of hemodialysis catheter infections was lower in period 2 (0 vs 7 [7%]; P = .006). Conclusions Increasing brachiocephalic AVF creation and reducing our reliance on radiocephalic AVFs resulted in a significant increase in primary functional patency at 1 year. This was achieved while maintaining the same high percentage of fistulas, a lower rate of central catheter infections, and the same low incidence of steal syndrome.

Cephalic arch stenosis is a common complication in maintenance hemodialysis (MHD) patients with brachial artery-cephalic vein fistulas and frequently leads to loss of the functioning brachial artery-cephalic vein fistula. There is paucity of conclusive data to guide appropriate management. We examined the risk of recurrence of cephalic arch stenosis after angioplasty compared to angioplasty after stent placement determined by angiography of the involved upper extremity over time in a contemporary cohort of MHD patients treated in two interventional nephrology practices from March 2008 through May 2011. We retrospectively identified 45 MHD patients with evidence of cephalic arch stenosis (age 60 ± 30 years, 45% men) on elective angiograms. The median number of days until another angioplasty was required decreased, starting with a median of 91.5 days after the first, 70.5 days after the second, 85 days after the third, and 56 days after the fourth. Angioplasty is associated with a faster rate of recurrence of cephalic arch stenosis. The placement of intravascular stent seems to prolong the patency compared to angioplasty alone. Clinical trials with a larger sample size will better elucidate the value and timing of angioplasty versus stent placement in cephalic arch stenosis.

Aggressive NIH is a common histopathological lesion found at the sites of venous stenosis in arteriovenous fistula (AVF) and arteriovenous grafts (AVG). Inflammatory mediators have been proposed to play a pathogenic role in NIH, but there is paucity of data evaluating this hypothesis in clinical studies or in animal models. Serum levels of inflammatory mediators can potentially identify patients at high risk of AVF and AVG dysfunction. In a cross-sectional cohort study of 754 HD patients who were part of the NIED study cohort, we examined the associations between inflammatory markers including serum interleukin (IL) 1β, IL-6, C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) and type of vascular access. Unadjusted and multivariate-adjusted linear regression models were used. In addition, time-dependent regression model was used to assess the association between inflammatory markers and mortality. We observed that in the multivariate-adjusted model, inflammatory mediators interleukin-6 (IL-6), interleukin-1L-ß (IL-1ß), and C-reactive protein (CRP), the predicted value in hemodialysis patients, are lowest in patients with AVF and highest in central venous catheter (CVC) and AVG even in case-mix and malnutrition-inflammation complex syndrome (MICS)-adjusted models. IL-6 and CRP levels fall consistently in the same patients when AVG or CVC is changed to AVF and increase if the same patient changes access from AVF to AVG or CVC. Obesity is a risk factor for fistula failure and fistulas are associated with the lowest mortality compared with CVC and AVG. We did not find any statistically significant association between tumor necrosis factor-α (TNF- α) and vascular access outcomes. Higher levels of inflammatory mediators seen in CVC and AVG compared with AVF could potentially explain the higher mortality seen in patients with CVC and AVG compared with AVF.

The vast majority of arteriovenous grafts (AVG) have been constructed using expanded polytetrafluoroethylene (ePTFE). While ePTFE grafts have the advantage of being relatively inexpensive and easy to manufacture, distribute, ship, and store, their primary patency rates are disappointing when compared with the native AVF. Though use of arteriovenous fistulas (AVF) in the United States has increased substantially, approximately 25% of hemodialysis patients continue to use AVG as their vascular access. We present here a comprehensive review of biological grafts and their use in hemodialysis vascular access. In this review, we discuss the use of synthetics and then explore the evolution of biological grafts over the past 20 years, their clinical impact, and future challenges in widespread clinical use in hemodialysis patients. Provided are in depth descriptions of currently used nonbiological arteriovenous grafts and the recent approaches in increasing the patency of synthetic grafts. Recent technological advances using tissue-engineered AVGs have shown promise for patients receiving hemodialysis and their potential to provide an attractive, viable option for vascular access have been discussed.

Generic chronic kidney disease (CKD) can be defined by a lowered estimated glomerular filtration rate (eGFR) and/or “kidney damage,” the latter by abnormal albuminuria (>30 mg/d), imaging, urinalysis, or renal pathology, that persists for at least 3 months. According to current schema, any adult with an eGFR

The development of interventional nephrology has undoubtedly led to an improvement in patient care at many facilities across the United States. However, these services have traditionally been offered by interventional nephrologists in the private practice arena. While interventional nephrology was born in the private practice setting, several academic medical centers across the United States have now developed interventional nephrology programs. University Medical Centers (UMCs) that offer interventional nephrology face challenges, such as smaller dialysis populations, limited financial resources, and real or perceived political "turf" issues." Despite these hurdles, several UMCs have successfully established interventional nephrology as an intricate part of a larger nephrology program. This has largely been accomplished by consolidating available resources and collaborating with other specialties irrespective of the size of the dialysis population. The collaboration with other specialties also offers an opportunity to perform advanced procedures, such as application of excimer laser and endovascular ultrasound. As more UMCs establish interventional nephrology programs, opportunities for developing standardized training centers will improve, resulting in better quality and availability of nephrology-related procedures, and providing an impetus for research activities.

Objectives Brachiobasilic arteriovenous fistulas (BBAVF) can be performed in one or two stages. We compared primary failure rates, as well as primary and secondary patency rates of one- and two-stage BBAVF at two institutions. Methods Patients undergoing one- and two-stage BBAVF at two institutions were compared retrospectively with respect to age, sex, body mass index, use of preoperative venous duplex ultrasound, diabetes, hypertension, and cause of end-stage renal disease. Categorical variables were compared using chi-square and Fisher's exact test, whereas the Wilcoxon rank-sum test was used to compare continuous variables. Patency rates were assessed using the Kaplan-Meier survival analysis and the Cox proportional hazards model with propensity analysis to determine hazard ratios. Results Ninety patients (60 one-stage and 30 two-stage) were identified. Mean follow-up was 14.2 months and the mean time interval between the first and second stage was 11.2 weeks. Although no significant difference in early failure existed (one-stage, 22.9% vs two-stage, 9.1%; P = .20), the two-stage BBAVF showed significantly improved primary functional patency at 1 year at 88% vs 61% ( P = .047) (hazard ratio, 0.2 (95% confidence interval [CI], .04–.80; P = .03). Patency for one-stage BBAVF markedly decreased to 34% at 2 years compared with 88% for the two-stage procedure ( P = .047). Median primary functional patency for one-stage BBAVF was 31 weeks (interquartile range [IQR], 11–54) vs 79 weeks (IQR, 29–131 weeks) for the two-stage procedure, respectively ( P = .0015). Two-year secondary functional patency for one- and two-stage procedures were 41% and 94%, respectively ( P = .015). Conclusions Primary and secondary patency at 1 and 2 years as well as functional patency is improved with the two-stage BBAVF when compared with the one-stage procedure. Lower primary failure rates prior to dialysis with the two-stage procedure approached, but did not reach statistical significance. While reasons for these finding are unclear, certain technical aspects of the procedure may play a role.

Increasing the creation of arteriovenous fistulas in the maintenance of hemodialysis patients is of great importance to the nephrology community. The creation of the brachial artery-basilic vein fistula is an important option in patients with unsuccessful or failing forearm accesses for hemodialysis. The aim of this study is to review reported outcomes of brachial artery-basilic vein fistulas regarding patency and primary failure rates in comparison with other types of fistulas and grafts in the published literature. We have also described the variations in the surgical technique during creation and the potential influence on outcomes. Based on our review of the literature, the rate of primary failure is approximately 15-20% with a range of 0-40%. The mean 1-year primary patency rate is approximately 72% with a range of 23-90%, and the 2-year primary patency rate is approximately 62% with a range from 11% to 86%. The number of required interventions to maintain patency is lower with brachial artery-basilic vein fistula compared to arteriovenous grafts.

Background: Racial/ethnic disparities prevail among hemodialysis patients. We hypothesized that significant differences exist between Black and non-Hispanic and Hispanic White hemodialysis patients in nutritional status, dietary intake and inflammation, and that they account for racial survival disparities. Methods: In a 6-year (2001–2007) cohort of 799 hemodialysis patients, we compared diet and surrogates of nutritional-inflammatory status and their mortality-predictabilities between 279 Blacks and 520 Whites using matched and regression analyses and Cox with cubic splines. Results: In age-, gender- and diabetes-matched analyses, Blacks had higher lean body mass and serum prealbumin, creatinine and homocysteine levels than Whites. In case-mix-adjusted analyses, dietary intakes in Blacks versus Whites were higher in energy (+293 ± 119 cal/day) and fat (+18 ± 5 g/day), but lower in fiber (–2.9 ± 1.3 g/day) than Whites. In both races, higher serum albumin, prealbumin and creatinine were associated with greater survival, whereas CRP and IL-6, but not TNF-α, were associated with increased mortality. The highest (vs. lowest) quartile of IL-6 was associated with a 2.4-fold (95% CI: 1.3–3.8) and 4.1-fold (2.2–7.2) higher death risk in Blacks and Whites, respectively. Conclusions: Significant racial disparities exist in dietary, nutritional and inflammatory measures, which may contribute to hemodialysis outcome disparities. Testing race-specific dietary and/or anti-inflammatory interventions is indicated.

Author(s): Molnar, Miklos Z; Lukowsky, Lilia R; Streja, Elani; Dukkipati, Ramanath; Jing, Jennie; Nissenson, Allen R; Kovesdy, Csaba P; Kalantar-Zadeh, Kamyar | Abstract: BackgroundIn maintenance dialysis patients, low blood pressure (BP) values are associated with higher death rates when compared with normal to moderately high values. This 'hypertension paradox' may be related to comorbid conditions. Dialysis patients with polycystic kidney disease (PKD) usually have a lower comorbidity burden and greater survival. We hypothesized that in PKD dialysis patients, a representative of a healthier dialysis patient population, high BP is associated with higher mortality.MethodsTime-dependent survival models including after multivariate adjustment were examined to assess the association between prehemodialysis and posthemodialysis BP and all-cause mortality in a 5-year cohort of 67 085 non-PKD and 1579 PKD hemodialysis patients.ResultsIn PKD patients, low prehemodialysis and posthemodialysis SBPs were associated with increased mortality, whereas high prehemodialysis DBP was associated with greater survival. Fully adjusted death hazard ratios (and 95% confidence levels) for prehemodialysis and posthemodialysis BP of less than 120 mmHg (reference 140 to l160 mmHg) were 1.30 (1.06-1.92) and 1.45 (1.04-2.02), respectively, and for prehemodialysis DBP of 80 mmHg or more (reference 70 to l80 mmHg) was 0.68 (0.49-0.93, all P values l0.05). Similar associations were observed in non-PKD patients. In pooled analyses, within each commensurate BP stratum, PKD patients exhibited superior survival to non-PKD patients.ConclusionAmong hemodialysis patients, those with PKD display a similar BP paradox as those without PKD, even though within each BP category PKD patients maintain superior survival. Randomized clinical trials are needed to define optimal blood pressure targets in the hemodialysis population.

An appreciation of the inherent risks with radiation exposure to patients and to the physician performing the procedure and the staff is urgently needed. The objective of this study is to assess radiation exposure to both patients and interventional nephrologists performing procedures and see any trends in the procedure and fluoroscopy times over a 2-year period. A total of 400 procedures performed at our vascular access center by a new to practice interventional nephrologist were recorded and retrospectively analyzed. Fluoroscopic time and procedure time for various procedures over the course of 2 years were recorded. This data were subsequently separated into eight groups (four quarters per year) based on the date of the procedure. Our study demonstrates a decrease in mean and median fluoroscopy times and procedure times for newly trained interventional with gain in number of procedures. The mean fluoroscopy time for the first two quarters was 5 minutes and 4 seconds, and the median was 3 minutes and 37 seconds. The mean procedure time for the first two quarters was 38 minutes, and the median was 32 minutes. The mean fluoroscopy time for the last two quarters was 1 minute and 54 seconds, and the median was 1 minute and 26 seconds. The mean procedure time for the last two quarters was 27 minutes, and the median was 21 minutes. In conclusion, gain of experience by the practicing Interventional Nephrologist from performing an increasing number of procedures leads to decreased procedure times and fluoroscopy times, which lowers the risk of radiation.

Background: Larger body size is associated with greater survival in maintenance hemodialysis (MHD) patients. It is not clear how lean body mass (LBM) and fat mass (FM) compare in their associations with survival across sex in these patients. Objective: We examined the hypothesis that higher FM and LBM are associated with greater survival in MHD patents irrespective of sex. Design: In 742 MHD patients, including 31% African Americans with a mean (±SD) age of 54 ± 15 y, we categorized men (n = 391) and women (n = 351) separately into 4 quartiles of near-infrared interactance–measured LBM and FM. Cox proportional hazards models estimated death hazard ratios (HRs) (and 95% CIs), and cubic spline models were used to examine associations with mortality over 5 y (2001–2006). Results: After adjustment for case-mix and inflammatory markers, the highest quartiles of FM and LBM were associated with greater survival in women: HRs of 0.38 (95% CI: 0.20, 0.71) and 0.34 (95% CI: 0.17, 0.67), respectively (reference: first quartile). In men, the highest quartiles of FM and percentage FM (FM%) but not of LBM were associated with greater survival: HRs of 0.51 (95% CI: 0.27, 0.96), 0.45 (95% CI: 0.23, 0.88), and 1.17 (95% CI: 0.60, 2.27), respectively. Cubic spline analyses showed greater survival with higher FM% and higher “FM minus LBM percentiles” in both sexes, whereas a higher LBM was protective in women. Conclusions: In MHD patients, higher FM in both sexes and higher LBM in women appear to be protective. The survival advantage of FM appears to be superior to that of LBM. Clinical trials to examine the outcomes of interventions that modify body composition in MHD patients are indicated.

Recent evidence suggests that the traditional syndromes known as renal osteodystrophy, secondary hyperparathyroidism, and vitamin D deficiency are related to mortality in persons with moderate to advanced chronic kidney disease (CKD). The so-called ‘kidney bone disease', also known as ‘mineral and bone disorders', is defined to include bone disorders, mineral disarrays, and vascular calcification. We have identified 14 common and clinically relevant conditions of contemporary nature that are related to the kidney bone disease, including calcitriol (active vitamin D) deficiency, 25(OH)-vitamin D deficiency, biochemical hyperparathyroidism, relatively low parathyroid hormone (PTH) level, increased serum alkaline phosphatase (hyperphosphatasemia), elevated fibroblast growth factor (FGF)-23, high turnover bone disease, adynamic bone disease, uremic osteoporosis, vascular calcification, hyper- and hypophosphatemia, and hyper- and hypocalcemia. We present a critical review of these 14 conditions with emphasis on patient survival and other pertinent clinical outcomes. We also review unresolved controversies surrounding the management of these conditions by administration of nutritional vitamin D (ergocalciferol and cholecalciferol), vitamin D receptor activators (calcitriol, alphacalcidiol, doxercalciferol), D-mimetics (paricalcitol, maxacalcitol), calcimimetics (cinacalcet), recombinant PTH (teriparatide), and receptor activator of nuclear factor-κB ligand modulators (denosumab); compare mortality predictability of PTH and alkaline phosphatase; and examine potential risks of bone disorders and mineral disarrays in CKD patients.

Many patients with chronic kidney disease (CKD), particularly those with stage 5 CKD, have protein wasting. The degree to which increased morbidity and mortality seen in these patients is due to protein depletion rather than to the often accompanying comorbidity is not clear. High protein diets lead to the accumulation of metabolites of protein that are potentially toxic. The MDRD Study, which investigated the effects of three levels of dietary protein and phosphorus intakes and two blood pressure goals on the progression of CKD, has several limitations. Several meta-analyses have examined the effects of low protein diets (LPD) on the progression of CKD. It is possible that the lower SUN levels or lesser degree of uremic symptoms may have contributed to the positive findings of LPD in the meta-analyses of Fouque and Pedrini et al., when compared with the study of Kasiske et al. A number of published reports indicate that LPD provide adequate protein for almost all clinically stable CKD patients and do not adversely affect body composition. In general, there are no large differences in the protein intake recommended by different expert groups for a given stage of CKD.

© 2015 National Kidney Foundation, Inc. Background In the general population, circulating adiponectin is associated with a favorable cardiovascular risk profile (eg, lower triglycerides and body fat) and decreased mortality. Hemodialysis (HD) patients have comparatively higher adiponectin concentrations, but prior studies examining the adiponectin-mortality association in this population have not accounted for body composition or shown a consistent relationship. Study Design Prospective cohort study. Settings & Participants We examined baseline serum adiponectin concentrations in 501 HD patients across 13 dialysis centers from the prospective MADRAD (Malnutrition, Diet, and Racial Disparities in Chronic Kidney Disease) cohort (entry period, October 2011 to February 2013; follow-up through August 2013). Predictor Serum adiponectin concentration in tertiles (tertiles 1, 2, and 3 defined as ≤16.1, 30.1, and ≥30.1-100.0 μg/mL, respectively). Adjustment variables included case-mix and laboratory test results (age, sex, race, ethnicity, vintage, diabetes, serum albumin, total iron-binding capacity, serum creatinine, white blood cell count, phosphate, hemoglobin, and normalized protein catabolic rate), body composition surrogates (subcutaneous, visceral, and total-body fat and lean body mass), and serum lipid levels (cholesterol, high-density lipoprotein cholesterol, and triglycerides). Outcomes All-cause mortality using survival (Cox) models incrementally adjusted for case-mix and laboratory test results. Results Among 501 HD patients, 50 deaths were observed during 631.1 person-years of follow-up. In case-mix- and laboratory-adjusted Cox analyses, the highest adiponectin tertile was associated with increased mortality versus the lowest tertile (HR, 3.35; 95% CI, 1.50-7.47). These associations were robust in analyses that additionally accounted for body composition (HR, 3.18; 95% CI, 1.61-8.24) and lipid levels (HR, 3.64; 95% CI, 1.34-7.58). Limitations Residual confounding cannot be excluded. Conclusions Higher adiponectin level is associated with a 3-fold higher death risk in HD patients independent of body composition and lipid levels. Future studies are needed to elucidate underlying mechanisms and determine therapeutic targets associated with improved outcomes in HD patients.

Normal sensory transduction requires the efficient disposal of acid (H+) generated by neuronal and sensory receptor activity. Multiple highly sensitive transport mechanisms have evolved in prokaryotic and eukaryotic organisms to maintain acidity within strict limits. It is currently assumed that the multiplicity of these processes provides a biological robustness. Here we report that the visual and auditory systems have a specific requirement for H+ disposal mediated by the sodium bicarbonate cotransporter NBC3 (refs. 7,8). Mice lacking NBC3 develop blindness and auditory impairment because of degeneration of sensory receptors in the eye and inner ear as in Usher syndrome. Our results indicate that in certain sensory organs, in which the requirement to transduce specific environmental signals with speed, sensitivity and reliability is paramount, the choice of the H+ disposal mechanism used is limited.

Protein-energy wasting (PEW) is common in patients receiving chronic hemodialysis and is one of the strongest risk factors for adverse outcomes and death in chronic dialysis patients. Although PEW may be the result of non-nutritional disorders, dietary interventions such as enteral nutrition or enteral tube feeding may improve nutritional status and outcomes. However, many patients are either not suitable or reluctant to accept enteral feeding or enteral tube feeding as a method of nutritional intake or cannot receive sufficient nutrients to satisfy their daily requirements by enteral nutrition. Intradialytic parenteral nutrition (IDPN) offers an alternative method for providing additional nutrients to a patient undergoing maintenance hemodialysis (MHD). Non-randomized studies and randomized studies which examined the effectiveness of IDPN are limited, but suggest that IDPN may improve the nutritional status of many MHD patients with PEW. However, data do not allow definitive conclusions to be drawn. Experimental evidence suggests that intraperitoneal nutrition may improve nutritional status in patients with PEW receiving peritoneal dialysis. Several studies suggest that supplemental amino acids may be provided to MHD patients through hemodialysate.

Objective To determine whether the association of body size and muscle mass with survival among patients undergoing long-term hemodialysis (HD) is consistent across race, especially in East Asian vs white and African American patients. Patients and Methods Using data from 20,818 patients from South Korea who underwent HD from February 1, 2001, to June 30, 2009, and 20,000 matched patients from the United States (10,000 whites and 10,000 African Americans) who underwent HD from July 1, 2001, to June 30, 2006, we compared mortality associations of baseline body mass index (BMI) and serum creatinine level as likely surrogates of obesity and muscle mass across the 3 races. Results In Korean HD patients, higher BMI together with higher serum creatinine levels were associated with greater survival, as previously reported from US and European studies. In the matched cohort (10,000 patients from each of the 3 races), mortality risks were lower across higher BMI and serum creatinine levels, and these associations were similar in all 3 races (reference groups: patients with BMI >25.0 kg/m 2 or serum creatinine >12 mg/dL in each race). White, African American, and Korean patients with BMI levels of 18.5 kg/m 2 or less (underweight) had 78%, 79%, and 57% higher mortality risk, respectively, and white, African American, and Korean patients with serum creatinine levels of 6.0 mg/dL or less had 108%, 87%, and 78% higher mortality, respectively. Conclusion This study shows that race does not modify the association of higher body size and muscle mass with greater survival in HD patients. Given the consistency of the obesity paradox, which may be related to a mitigated effect of protein-energy wasting on mortality irrespective of racial disparities, nutritional support to improve survival should be tested in HD patients of all races.

The vast majority of arteriovenous grafts (AVG) have been constructed using expanded polytetrafluoroethylene (ePTFE). While ePTFE grafts have the advantage of being relatively inexpensive and easy to manufacture, distribute, ship, and store, their primary patency rates are disappointing when compared with the native AVF. Though use of arteriovenous fistulas (AVF) in the United States has increased substantially, approximately 25% of hemodialysis patients continue to use AVG as their vascular access. We present here a comprehensive review of biological grafts and their use in hemodialysis vascular access. In this review, we discuss the use of synthetics and then explore the evolution of biological grafts over the past 20 years, their clinical impact, and future challenges in widespread clinical use in hemodialysis patients. Provided are in depth descriptions of currently used nonbiological arteriovenous grafts and the recent approaches in increasing the patency of synthetic grafts. Recent technological advances using tissue-engineered AVGs have shown promise for patients receiving hemodialysis and their potential to provide an attractive, viable option for vascular access have been discussed.

Background Low serum albumin is common and associated with protein-energy wasting, inflammation, and poor outcomes in maintenance hemodialysis (MHD) patients. We hypothesized that in-center (in dialysis clinic) provision of high-protein oral nutrition supplements (ONS) tailored for MHD patients combined with anti-oxidants and anti-inflammatory ingredients with or without an anti-inflammatory appetite stimulator (pentoxifylline, PTX) is well tolerated and can improve serum albumin concentration. Methods Between January 2008 and June 2010, 84 adult hypoalbuminemic (albumin

The Charlson comorbidity index (CCI) is a commonly used scale for assessing morbidity, but its role in assessing mortality in hemodialysis patients is not clear. Age, a component of CCI, is a strong risk factor for morbidity and mortality in chronic diseases and correlates with comorbidities. We hypothesized that the Charlson comorbidity index without age is a strong predictor of mortality in hemodialysis patients.A 6-year cohort of 893 hemodialysis patients was examined for an association between a modified CCI (without age and kidney disease) (mCCI) and mortality.Patients were 53±15 years old (mean±SD), had a median mCCI score of 2, and included 47% women, 31% African Americans and 55% diabetics. After adjusting for case-mix and nutritional and inflammatory markers including C-reactive protein and interleukin-6, 2nd (mCCI: 1-2), 3rd (mCCI=3), and 4th (mCCI: 4-9) quartiles compared to 1st (mCCI=0) quartiles showed death hazard ratios (95% confidence intervals) of 1.43 (0.92-2.23), 1.70 (1.06-2.72), and 2.33 (1.43-3.78), respectively. The mCCI-death association was robust in non-African Americans. The CCI-death association linearity was verified in cubic splines. Each 1 unit higher mCCI score was associated with a death hazard ratio of 1.16 (1.07-1.27).CCI independent of age is a robust and linear predictor of mortality in hemodialysis patients, in particular in non-African Americans.

The development of interventional nephrology has undoubtedly led to an improvement in patient care at many facilities across the United States. However, these services have traditionally been offered by interventional nephrologists in the private practice arena. While interventional nephrology was born in the private practice setting, several academic medical centers across the United States have now developed interventional nephrology programs. University Medical Centers (UMCs) that offer interventional nephrology face challenges, such as smaller dialysis populations, limited financial resources, and real or perceived political "turf" issues." Despite these hurdles, several UMCs have successfully established interventional nephrology as an intricate part of a larger nephrology program. This has largely been accomplished by consolidating available resources and collaborating with other specialties irrespective of the size of the dialysis population. The collaboration with other specialties also offers an opportunity to perform advanced procedures, such as application of excimer laser and endovascular ultrasound. As more UMCs establish interventional nephrology programs, opportunities for developing standardized training centers will improve, resulting in better quality and availability of nephrology-related procedures, and providing an impetus for research activities.

Purpose We aim to assess the effect of regional block anesthesia on vein diameter, type of AVF placement, and fistula size and flow volume. Methods 30 patients presenting for AV access procedures were followed prospectively. Vein diameters via venous ultrasound and planned location for AV access were documented. Supraclavicular brachial plexus block was followed by repeat ultrasound and alterations in operative plan were noted. Patients returned to clinic for duplex ultrasound assessment. Results Average increase from baseline vein diameter with regional block was most pronounced in the lower cephalic (34%), upper cephalic (24.2%), and basilic veins (31.3%) and less in the brachial vein (8.7%). Type of AVF was modified following regional block in 14%. The rate of native AVF placement improved from 89% to 93% with regional block. Twenty-three AVF patients were available for follow-up (mean 24 weeks). Average fistula size was 7.9 mm (CI 6.9–8.9) and all patent fistulas developed flow volume >600 mL/min. Primary patency was attained in 83%. One thrombosis occurred after a basilic artery was lacerated during dialysis access. The average fistula increased 0.33 cm from post-block diameter (SD 0.22, PConclusions Vein diameter increases significantly in the basilic and cephalic veins following regional block anesthesia and may improve the rate of native fistula placement. Propensity to dilate after regional block anesthesia does not predict size of the fistula.

Increasing the creation of arteriovenous fistulas in the maintenance of hemodialysis patients is of great importance to the nephrology community. The creation of the brachial artery-basilic vein fistula is an important option in patients with unsuccessful or failing forearm accesses for hemodialysis. The aim of this study is to review reported outcomes of brachial artery-basilic vein fistulas regarding patency and primary failure rates in comparison with other types of fistulas and grafts in the published literature. We have also described the variations in the surgical technique during creation and the potential influence on outcomes. Based on our review of the literature, the rate of primary failure is approximately 15-20% with a range of 0-40%. The mean 1-year primary patency rate is approximately 72% with a range of 23-90%, and the 2-year primary patency rate is approximately 62% with a range from 11% to 86%. The number of required interventions to maintain patency is lower with brachial artery-basilic vein fistula compared to arteriovenous grafts.

In individuals with advanced chronic kidney disease, secondary hyperparathyroidism is known to be associated with high turnover bone disease. Low serum parathyroid hormone (PTH) levels may not necessarily be because of hypodynamic bone, but could be another facet of the malnutrition-inflammation-cachexia syndrome (MICS). A recent 5-year cohort study in 748 stable hemodialysis outpatients showed that after the confounding effect by the MICS was removed, the moderately low levels of PTH in the 100 to 150 pg/mL range was associated with the greatest survival rate. Data from Japanese dialysis patients show similar survival advantages of having a lower PTH range. Low levels of serum PTH seem to be associated with markers of protein-energy wasting and inflammation, and this association may confound the relationship between serum PTH and alkaline phosphatase. PTH stimulates lipogenesis through influx of calcium into the adipocytes. PTH secretion is suppressed by interleukin-1 beta and interleukin-6, which are proinflammatory cytokines that are associated with poor outcome in dialysis patients. These cytokines inhibits PTH secretion in cultured parathyroid tissue slices. In this article, we review the association of a low serum PTH level with the MICS in patients with chronic kidney disease and suggest avoiding over-interpretation of low serum PTH level as an indicator of low turnover bone disease.

An appreciation of the inherent risks with radiation exposure to patients and to the physician performing the procedure and the staff is urgently needed. The objective of this study is to assess radiation exposure to both patients and interventional nephrologists performing procedures and see any trends in the procedure and fluoroscopy times over a 2-year period. A total of 400 procedures performed at our vascular access center by a new to practice interventional nephrologist were recorded and retrospectively analyzed. Fluoroscopic time and procedure time for various procedures over the course of 2 years were recorded. This data were subsequently separated into eight groups (four quarters per year) based on the date of the procedure. Our study demonstrates a decrease in mean and median fluoroscopy times and procedure times for newly trained interventional with gain in number of procedures. The mean fluoroscopy time for the first two quarters was 5 minutes and 4 seconds, and the median was 3 minutes and 37 seconds. The mean procedure time for the first two quarters was 38 minutes, and the median was 32 minutes. The mean fluoroscopy time for the last two quarters was 1 minute and 54 seconds, and the median was 1 minute and 26 seconds. The mean procedure time for the last two quarters was 27 minutes, and the median was 21 minutes. In conclusion, gain of experience by the practicing Interventional Nephrologist from performing an increasing number of procedures leads to decreased procedure times and fluoroscopy times, which lowers the risk of radiation.

Low serum parathyroid hormone (PTH) has been implicated as a primary biochemical marker of adynamic bone disease in individuals with chronic kidney disease (CKD) who undergo maintenance hemodialysis (MHD) treatment. We hypothesized that the malnutrition-inflammation complex is associated with low PTH levels in these patients and confounds the PTH-survival association.We examined 748 stable MHD outpatients in southern California and followed them for up to 5 years (October 2001-December 2006).In 748 MHD patients, serum PTH150pg/mL was more prevalent among non-blacks and diabetics. There was no association between serum PTH and coronary artery calcification score, bone mineral density, or dietary protein or calorie intake. Low serum PTH was associated with markers of protein-energy wasting and inflammation, and this association confounded the relationship between serum PTH and alkaline phosphatase. Although 5-year crude mortality rates were similar across PTH increments, after adjustment for the case-mix and surrogates of malnutrition and inflammation, a moderately low serum PTH in 100-150pg/mL range was associated with the greatest survival compared to other serum PTH levels, i.e., a death hazard ratio of 0.52 (95% confidence interval: 0.29-0.92, p0.001) compared to PTH of 300-600pg/mL (reference).Low serum PTH may be another facet of the malnutrition-inflammation complex in CKD, and after controlling for this confounder, a moderately low PTH in 100-150pg/mL range appears associated with the greatest survival. Limitations of observational studies should be considered.

Protein-energy wasting (PEW) is highly prevalent in people with stages 4 and 5 chronic kidney disease, particularly in maintenance dialysis patients, and many indicators of PEW correlate strongly with mortality. Consequently, the causes, prevention, and treatment of PEW are active areas of investigation. A major cause of PEW is insufficient intake of nutrients, especially protein and energy (calories). Standard methods for increasing nutritional intake in patients with chronic kidney disease with PEW include dietary counseling and use of food supplements. If nutrient intake does not increase sufficiently, tube feeding and total parenteral nutrition may be considered. For maintenance hemodialysis patients, intradialytic parenteral nutrition (IDPN), an intravenous infusion of essential nutrients during hemodialysis treatments, may be used. Many studies have evaluated the effectiveness and safety of IDPN and show that IDPN has a good safety profile and also may improve protein-energy status. However, most studies have limitations in experimental design, such as small numbers of patients, lack of adequate controls, inclusion of patients without PEW, uncontrolled or unmonitored oral intake, nonrandomized design, or short duration. Additionally, most studies used nutritional or inflammatory indicators, rather than the more important outcomes of morbidity, mortality, or quality of life. Thus, although IDPN may partially satisfy the nutritional needs of maintenance hemodialysis patients who have or are at risk of PEW and who have substantial, but not adequate, protein and/or energy intake, longer term randomized prospective clinical trials with appropriate control groups are necessary to more definitively evaluate the clinical effectiveness and indications for IDPN.