Canadian Hemodialysis Morbidity Study

Use of vascular access methods for hemodialysis in Serbia: Results from SerbVasc registry

INTRODUCTION

In many countries, hemodialysis is still the most common method of renal replacement. Significant regional variations exist in creating and maintaining vascular access for hemodialysis. Therefore, analyzing national registries with vascular access data is essential for developing effective national treatment strategies. The Serbian national vascular surgery registry was established as part of the VascuNet collaboration network in 2019. The registry comprehensively records vascular procedures across Serbia, including those related to vascular access for hemodialysis.

OBJECTIVES

This study aims to evaluate the prevalence of different vascular access methods for hemodialysis in Serbia, focusing on both new and prevalent patients and examining demographic differences and risk factors.

PATIENTS AND METHODS

The data were collected from the vascular accesses section of the SerbVasc registry over a 3-year observational period, focusing on the following aspects: number of incident and prevalent patients with types of vascular access, as well as comparison of patients with arteriovenous fistulas (AVF), arteriovenous grafts (AVG), central venous catheters (CVC), and tCVC based on age, gender, smoking, and comorbidities.

RESULTS

There were total of 1024 incident hemodialysis patients. AVF was created in 219 patients (21.4%), AVG in 5 patients (0.5%), and tCVC in 150 patients (14.6%), while hemodialysis via CVC was initiated in 650 (63.5%) patients. The total number of permanent vascular accesses for HD was 1402, comprising 686 (48.9%) distal AFVs, 220 (15.7%) proximal AVFs, 91 (6.4%) AVGs, and 405 (28.8%) tCVCs. The prevalence of current smoking was highest in the tCVC (48.3%) and lowest in the dAVF group (18.40%).

CONCLUSION

The percentage of patients starting hemodialysis with AVF remains suboptimal. tCVC is used substantially as first and permanent access, particularly among older patients.

Editor's Choice - Outcomes of Cold Stored Saphenous Vein Allografts for Haemodialysis Vascular Access

OBJECTIVE

The aim of this study was to evaluate the outcomes of cold stored saphenous vein allografts (CSVAs) for haemodialysis vascular access.

METHODS

A retrospective, two centre study was conducted between January 2016 and December 2020 of all patients who had CSVA placement for haemodialysis vascular access. Primary, primary assisted, and secondary patency were analysed, as well as procedural complications and re-interventions.

RESULTS

One hundred and nine patients (n = 55 women) with a mean age of 67.2 ± 13.6 years, with no options for creating an autogenous arteriovenous fistula, were included in the study. At one year, primary, primary assisted, and secondary patency were 37.6%, 59.0%, and 73.3%, respectively; and at two years 19.9%, 42.5%, and 54.9%, respectively. During a mean follow up period of 26 ± 18 months, five patients (4.6%) had an access infection, with no related death. During the follow up period, 32 patients (29.4%) died and 13 patients (11.9%) underwent a kidney transplant. None of these patients showed immunoconversion before transplantation. The cumulative incidence of adverse events by the Fine-Gray method was calculated. Considering competing risks (death and renal transplantation), 9.2% of patients lost their vascular access at one year and 18% at two years. Moreover, 57.8% patients had stenosis, mainly on the outflow (45.9%), and 49.5% had thrombosis.

CONCLUSION

With a comparable patency rate associated with a low infection rate, CSVA offers a potential alternative to expanded polytetrafluoroethylene grafts. This creates haemodialysis vascular access when the venous capital is exhausted in patients with reported risk factors for vascular access infection, i.e., insertion in the thigh, advanced age, diabetes mellitus, immunocompromised state, obesity, or revision of an infected prosthetic graft.

Single-Center Experience on Growth in Infants Born With End-Stage Kidney Disease

OBJECTIVES

Children with chronic kidney disease display poor growth that impacts health outcomes; data on infants with severe congenital anomalies of the kidney and urinary tract (CAKUT) are limited. We examined growth patterns in infants with CAKUT requiring dialysis in the first 30 days.

METHODS

This study evaluated infants with severe CAKUT from 2014 to 2018 surviving past 30 days. Somatic growth parameters as per standard infant curves and nutritional information were recorded.

RESULTS

Twenty four infants met inclusion criteria. Seventeen infants received dialysis, demonstrating somatic growth disruption most profound at a 1-2 months postnatal age. Growth trends were improved compared to infants with CAKUT who did not require dialysis. Linear growth failed to normalize by 1 year of age.

CONCLUSIONS

Infants with severe CAKUT are at high risk for early growth failure. Understanding of this deficit and impacts of early dialysis on growth and long-term outcomes are needed to identify targeted nutritional strategies.

Role of Antiplatelet Therapy in Hemodialysis Arteriovenous Graft Secondary Patency Following Successful Percutaneous Thrombectomy

PURPOSE

The purpose of this study was to elicit the relationship of antiplatelet therapy (AP) in maintaining arteriovenous graft (AVG) patency after successful percutaneous pharmacomechanical thrombectomy ("declot").

MATERIALS AND METHODS

This was an institutional review board-approved retrospective review of AVG declot procedures between July 2019 and August 2020. AVG characteristics, bleeding complications, anticoagulation and antiplatelet medication regimens, and thrombosis free survival were evaluated. Recurrent time-to-event analysis was performed using a Prentice-Williams-Peterson Gap time model was performed to evaluate AVG thrombosis free survival.

RESULTS

A total of 109 declots were technically successful and performed in 63 individual patients. The majority of procedures were performed in upper arm grafts (71%, n = 45). Dual antiplatelet (DAPT) was prescribed after 52 declots (48%), single antiplatelet was prescribed after 36 declots (33%), and anticoagulation was prescribed after 31 declots (28%). Median thrombosis free survival was 37 days (range 1-412 days) in the no antiplatelet group, 84 days (range 1-427 days) in the single antiplatelet group, and 93 days (range 3-407 days) in the DAPT group. Anti-platelet medications trended towards protective of AVG thrombosis in multivariate analysis (hazard ratio 0.84, 95% confidence interval 0.60-1.19); however, this did not reach statistical significance (P = 0.33). A total of 4 major and 5 minor bleeding events occurred.

CONCLUSION

The results of this study support further evaluation of AP therapy in preventing secondary rethrombosis of dialysis AVG.

Luminal pressure gradient and risk of arteriovenous fistula nonmaturation

While arteriovenous fistula (AVF) nonmaturation is a major issue of hemodialysis care, an effective treatment to improve AVF maturation remains lacking. AVF introduces pulsatile arterial blood flow into its venous limb and produces high luminal pressure gradient, which may have adverse effect on vascular remodeling. As such, the aim of the present study is to investigate effect of luminal pressure gradient on AVF nonmaturation. This single-center, prospective observational study includes patients receiving autologous AVF creation. Participants received early postoperative ultrasound 5-7 days after surgery to collect parameters including diameters, flow rates, and volume at inflow and outflow sites. Luminal pressure gradient was estimated by using modified Bernoulli equation. The outcome was spontaneous AVF maturation within 8 weeks after surgery without intervention. Thirty patients were included, of which the mean age was 66.9 years and 70% were male. At the end of study, 13 (43.3%) patients had spontaneous AVF maturation. All demographic and laboratory characteristics were similar between patients with mature and nonmature AVF. Regarding ultrasonographic parameters, nonmature AVF showed significantly higher inflow/outflow diameter ratio, inflow velocity, and luminal pressure gradient. While these 3 parameters were significantly correlated, multivariate logistic regression showed their significant association with AVF nonmaturation. Receiver operating characteristic curve exhibited their high predictive value for AVF nonmaturation. Our findings showed that higher inflow/outflow ratio, inflow velocity, and AVF luminal pressure gradient in early postoperative ultrasound predicted risk of AVF nonmaturation. Reducing inflow/outflow diameter ratio or inflow rate may be an approach to improve AVF maturation. The predictive value of this early assessment might have impact on the clinical practice of AVF care.

The Disconnect Between Extracorporeal Circulation and the Microcirculation: A Review

Extracorporeal circulation (ECC) procedures, such as cardiopulmonary bypass (CPB) and extracorporeal membrane oxygenation (ECMO), take over the function of one or more organs, providing clinicians time to treat underlying pathophysiological conditions. ECMO and CPB carry significant mortality rates for patients, despite prior decades of research focused on the resulting failure of critical organs. Since the focus of these procedures is to support blood flow and provide oxygen-rich blood to tissues, a shift in research toward the effects of ECMO and CPB on the microcirculation is warranted. Along with provoking systemic responses, both procedures disrupt the integrity of red blood cells, causing release of hemoglobin (Hb) from excessive foreign surface contact and mechanical stresses. The effects of hemolysis are especially pronounced in the microcirculation, where plasma Hb leads to nitric oxide scavenging, oxidization, formation of reactive oxygen species, and inflammatory responses. A limited number of studies have investigated the implications of ECMO in the microcirculation, but more work is needed to minimize ECMO-induced reduction of microcirculatory perfusion and consequently oxygenation. The following review presents existing information on the implications of ECMO and CPB on microvascular function and proposes future studies to understand and leverage key mechanisms to improve patient outcomes.

Medical adjuvant treatment to increase patency of arteriovenous fistulae and grafts

BACKGROUND

People with end-stage renal disease (ESRD) often require either the formation of an arteriovenous fistula (AVF) or an interposition prosthetic arteriovenous graft (AVG) for haemodialysis. These access sites should ideally have a long life and a low rate of complications (e.g. thrombosis, infection, stenosis, aneurysm formation and distal limb ischaemia). Although some of the complications may be unavoidable, any adjuvant technique or medical treatment aimed at decreasing complications would be welcome. This is the fourth update of the review first published in 2003.

OBJECTIVES

To assess the effects of adjuvant drug treatment in people with ESRD on haemodialysis via autologous AVFs or prosthetic interposition AVGs.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and ClinicalTrials.gov trials register to 6 August 2020.

SELECTION CRITERIA

Randomised controlled trials of active drug versus placebo in people with ESRD undergoing haemodialysis via an AVF or prosthetic interposition AVG.

DATA COLLECTION AND ANALYSIS

For this update, two review authors (IM, MFAK) independently selected trials for inclusion, extracted data, assessed risk of bias and assessed the certainty of the evidence according to GRADE. We resolved disagreements by discussion or consultation with another review author (ADS). The primary outcome was the long-term fistula or graft patency rate. Secondary outcomes included duration of hospital stay; complications such as infection, aneurysm formation, stenosis and distal limb ischaemia; and number of related surgical or radiological interventions.

MAIN RESULTS

For this update, one additional study was suitable for inclusion, making a total of 13 trials with 2080 participants. Overall the certainty of the evidence was low or moderate due to short follow-up periods, heterogeneity between trials, small sample sizes, and risk of bias due to incomplete reporting. Medical adjuvant treatments used in the included trials were aspirin, ticlopidine, dipyridamole, dipyridamole plus aspirin, warfarin, fish oil, clopidogrel, sulphinpyrazone and glyceryl trinitrate (GTN) patch.  All included studies reported on graft patency by measuring graft thrombosis. There was insufficient evidence to determine if there was a difference in graft patency in studies comparing aspirin versus placebo (odds ratio (OR) 0.40, 95% confidence interval (CI) 0.07 to 2.25; 3 studies, 175 participants; low-certainty evidence). The meta-analysis for graft patency comparing ticlopidine versus placebo favoured ticlopidine (OR 0.45, 95% CI 0.25 to 0.82; 3 studies, 339 participants; moderate-certainty evidence). There was insufficient evidence to determine if there was a difference in graft patency in studies comparing fish oil versus placebo (OR 0.24, 95% CI 0.03 to 1.95; 2 studies, 220 participants; low-certainty evidence); and studies comparing clopidogrel and placebo (OR 0.40, 95% CI 0.13 to 1.19; 2 studies, 959 participants; moderate-certainty evidence). Similarly, there was insufficient evidence to determine if there was a difference in graft patency comparing the effect of dipyridamole versus placebo (OR 0.46, 95% CI 0.11 to 1.94; 1 study, 42 participants, moderate-certainty evidence) and dipyridamole plus aspirin versus placebo (OR 0.64, CI 0.16 to 2.56; 1 study, 41 participants; moderate-certainty evidence); comparing low-intensity warfarin with placebo (OR 1.76, 95% CI 0.78 to 3.99; 1 study, 107 participants; low-certainty evidence); comparing sulphinpyrazone versus placebo (OR 0.43, 95% CI 0.03 to 5.98; 1 study, 16 participants; low-certainty evidence) and comparing GTN patch and placebo (OR 1.26, 95% CI 0.63 to 2.54; 1 study, 167 participants; moderate-certainty evidence). The single trial evaluating warfarin was terminated early because of major bleeding events in the warfarin group. Only two studies published data on the secondary outcome of related interventions (surgical or radiological); there was insufficient evidence to determine if there was a difference in related interventions between placebo and treatment groups. None of the included studies reported on the duration of hospital stay.  Most studies reported complications ranging from mortality to nausea. However, data on complications were limited and reporting varied between studies.

AUTHORS' CONCLUSIONS

The meta-analyses of three studies for ticlopidine (an antiplatelet treatment), which all used the same dose of treatment but with a short follow-up of only one month, suggest ticlopidine may have a beneficial effect as an adjuvant treatment to increase the patency of AVFs and AVGs in the short term. There was insufficient evidence to determine if there was a difference in graft patency between placebo and other treatments such as aspirin, fish oil, clopidogrel, dipyridamole, dipyridamole plus aspirin, warfarin, sulphinpyrazone and GTN patch. The certainty of the evidence was low to moderate due to short follow-up periods, the small number of studies for each comparison, small sample sizes, heterogeneity between trials and risk of bias due to incomplete reporting. Therefore, it appears reasonable to suggest further prospective studies be undertaken to assess the use of these antiplatelet drugs in renal patients with an AVF or AVG.

[Complications of permanent vascular access for haemodialysis]

Permanent vascular access is the basis of renal replacement therapy by the method of programmed haemodialysis, on whose stable functioning depends the life of patients with end-stage renal disease. At the present time, there is significant deficit of scientific and methodological Russian-language literature on this problem, with no Russian consensus documents concerned. This article is a review of the contemporary world literature dedicated to the problem of permanent vascular access, including currently in force European (2018) and North American (2019) guidelines for good clinical practice, also discussing the problems of strategy and tactics of creating a permanent vascular access, monitoring its dysfunction, pathophysiology of functioning of arteriovenous fistulas. Presented herein are unified approaches to diagnosis and treatment of thrombolytic and haemorrhagic complications associated with the access, as well as local infectious and non-infectious complications. Special attention is paid to indications for the operation and rational therapeutic decision-making.

Circulating endothelial cells as predictor of long-term mortality and adverse cardiovascular outcomes in hemodialysis patients

Circulating endothelial cells (CEC) are thought to be markers of endothelial injury. We hypothesized that the numbers of CEC may provide a novel means for predicting long-term survival and cardiovascular events in hemodialysis patients. 54 hemodialysis patients underwent enumeration of their CEC number. We retrospectively analyzed their survival and incidence of adverse cardiovascular events. 22 deaths (41%) were noted over the median follow up period of 3.56 years (IQR 1.43-12) and 6 were attributed to cardiovascular deaths (11%) of which 1 (4%) was in the low CEC (CEC<20 cells/ml) and 5 (19%) in the high CEC (CEC≥20 cells/ml) group. High CEC was associated with worse cardiovascular survival (p = 0.05) and adverse cardiac events (p = 0.01). In multivariate analysis, CEC >20 cells/ml was associated with a 4-fold increased risk of adverse cardiac events (OR, 4.16 [95% CI,1.38-12.54],p = 0.01) while all-cause mortality and cardiovascular mortality were not statistically different. In this hemodialysis population, a single measurement of CEC was a strong predictor of long term future adverse cardiovascular events. We propose that CEC may be a novel biomarker for assessing cardiovascular risk in dialysis patients.

Arteriovenous Fistula Creation and Estimated Glomerular Filtration Rate Decline in Advanced CKD: A Matched Cohort Study

Background

Kidney failure is associated with a high burden of morbidity and mortality. Previous studies have raised the possibility that arteriovenous fistula (AVF) creation may attenuate eGFR decline. This study aimed to compare eGFR decline in predialysis patients with an AVF, matched to patients oriented toward peritoneal dialysis (PD).

Methods

Predialysis patients with an AVF and those oriented toward PD were retrospectively matched using a propensity score. Time zero was defined as the "AVF creation date" for the AVF group and the "date when eGFR was closest to the matched patient's eGFR at AVF creation" for the PD group. Crude and predicted eGFR decline in AVF and PD groups were compared before and after time zero using mixed-effect linear regressions.

Results

In total, 61 pairs were matched. Crude annual eGFR decline before AVF creation/time zero was -4.1 ml/min per m² per year in the AVF group versus -5.3 ml/min per m² per year in the PD group (P=0.75) and after time zero, -2.5 ml/min per m² per year in the AVF group versus -4.5 ml/min per m² per year in the PD group (P=0.02). The predicted annual decline decreased from -5.1 ml/min per m² per year in the AVF group before AVF creation to -2.8 ml/min per m² per year after (P<0.01), whereas there was no difference in the PD group (-5.5 versus -5.1 ml/min per m² per year respectively, P=0.41).

Conclusions

In this matched study, AVF creation was associated with a deceleration of kidney function decline compared with a control PD-oriented group. Prospective studies are needed to assess the potential mechanisms between vascular access creation and eGFR slope attenuation.

Role of Hypoalbuminemia in the Genesis of Cardiovascular Disease in Dialysis Patients

Our objective was to review the articles about the association between hypoalbuminemia and atherosclerotic or thrombotic cardiovascular disease (CVD) and to look for possible explanations for the role of hypoalbuminemia.

Increased incidences of CVD were reported in patients with hypoalbuminemia owing to renal or other diseases. Hypoalbuminemia increases plasma levels of lipoprotein(a), fibrinogen, and arachidonic acid metabolites; it also increases platelet aggregability and blood viscosity, all of which may contribute to the development of CVD. This cause-effect association is thought to be “dependent.” Changes in atherogenic lipoproteins or lipids, such as LDL cholesterol, triglycerides, and apolipoprotein B, are controversial in hypoalbuminemic dialysis patients, possibly because coexistent malnutrition and volume status can affect both albumin and lipids. In our recent study, there was a negative correlation between serum albumin and C-reactive protein, D-dimer (an index of intravascular thrombogenesis), and von Willebrand factor (a marker for endothelial cell injury), but infusion of albumin did not affect the level of these parameters, which suggests that the correlations may be an effect-effect association by a confounding variable, such as inflammation.

In conclusion, hypoalbuminemia is associated with cardiovascular disease via two pathways: one, a “dependent” cause-effect association; the other, an effect-effect association.

Erythropoietin Treatment Decreases Cardiovascular Morbidity and Mortality in Capd Patients

Objective

To analyze the effects of recombinant human erythropoietin (rHuEPO) therapy on cardiovascular (CV) morbidity and mortality among continuous ambulatory peritoneal dialysis (CAPD) patients.

Design

Retrospective comparative study.

Setting

CAPD unit in a university hospital.

Patients

Forty-two patients on rHuEPO treatment for at least one year were compared with an rHuEPO nonuser group of 113 patients. Subcutaneous rHuEPO doses were adjusted to a hemoglobin objective level of 10.5 -13.5 g/ dL. Fifty-seven patients were considered as high cardiovascular risk (HCVR), 17 in the rHuEPO group and 40 in the rHuEPO nonuser group. Ninety-eight patients were classified as low cardiovascular risk (LCVR), 25 of whom were in the rHuEPO group.

Results

The incidence of cardiovascular morbidity was more frequent in the rHuEPO nonuser than in the rHuEPO user group (40% vs 22%) and in HCVR than in LCVR patients (59.6% vs 20.4%). By multiple logistic regression analysis, the best model to explain the development of cardiovascular morbidity comprises rHuEPO treatment, CV risk, and age. In the rHuEPO user group, HCVR and LCVR patients did not show significant differences in survival, while in the rHuEPO nonuser group, HCVR patients had a lower survival rate than LCVR patients (p = 0.0003). Cox proportional hazards model revealed that LCVR patients had an excellent prognosis compared with HCVR patients in the rHuEPO nonuser group, but this difference disappeared in the rHuEPO user group.

Conclusion

These data show a beneficial effect of rHuEPO treatment on cardiovascular morbidity and mortality in CAPD patients, evidenced by the elimination of the correlation between prior cardiovascular risk and subsequent mortality.

Albumin and Amino Acid Levels as Markers of Adequacy in Continuous Ambulatory Peritoneal Dialysis

Similar to previous findings in HD patients, a markedly decreased serum albumin level has been found to be a strong predictor of morbidity and mortality in CAPD patients. However, a slight decrease in serum albumin levels (to about 30 g/L if measured with nephelometry or the bromcresol purple method) does not always seem to reflect impaired nutritional status or to be associated with an increased morbidity or mortality in CAPD patients. A low serum albumin level among CAPD patients is related to dialysate albumin loss, comorbidity, age, and a low dietary protein intake. The possible relation between the dialysis dose (as assessed by small solute clearances) and serum albumin levels among CAPD patients is much less established and needs further study, although serum albumin tends to increase in prospective studies of increased peritoneal dialysis dose.

Although the plasma levels of amino acids seem to be lower in CAPD patients compared to HD patients, this does not reflect the intracellular amino acid pattern in muscle which is less abnormal in CAPD patients, possibly because of the sustained hyperinsulinemia during CAPD, resulting in an in creased intracellular to extracellular gradient. It is at present not established to what extent the amino acid abnormalities are related to the dialysis dose.

Malnourished and hypoalbuminemic CAPD patients should be recommended to increase the protein intake, and if this is not effective, the dialysis dose should be increased. Furthermore, the use of amino acid-based peritoneal dialysis solutions is a promising new tool for the treatment of malnourished CAPD patients and may become an important component of CAPD therapy in the future. On the other hand, if the nutritional status deteriorates in spite of these efforts, the patient should be transferred to hemodialysis if possible.

Major and Minor Risk Factors for Cardiovascular Disease in Continuous Ambulatory Peritoneal Dialysis Patients

Uremia in general and peritoneal dialysis in particular bring with them risk factors for the development of cardiovascular disease. These factors include multiple lipid abnormalities, hyperhomocysteinemia, abdominal obesity, chronic inflammation, hypoalbuminemia, oxidative stress, and AGE formation. When these are combined with conventional risk factors, one can appreciate why the incidence of cardiovascular disease is so high in peritoneal dialysis patients. Treatment strategies should address each of these risks appropriately.

Lipid Parameters Including Lipoprotein (A) in Patients Undergoing CAPD and Hemodialysis

Objective

Oyslipidemia possibly contributes to the vascular complications commonly afflicting uremic patients. Lipoprotein (a) [Lp(a)] has been identified as an independent risk factor for atherosclerotic vascular dis ease. The aim of our study was to compare lipidparameters, including Lp(a), between hemodialysis (HO) and continuous ambulatory peritoneal dialysis (CAPO) patients.

Design

A cross-sectional study.

Setting

University Medical Center.

Participants

Forty CAPO and 40 HO patients carefully matched for age, sex, body mass index (BMI), smoking habits, and duration of dialysis were studied. A group of 40 healthy individuals matched for age, sex, BMI, and smoking habits was used as control.

Interventions

None.

Main Outcome Measures

Serum lipid parameters and atherogenic risk ratios were the main outcome measures.

Results

Both groups of dialysis patients had increased serum triglycerides and decreased levels of Apo AI and HOL cholesterol compared to controls. Moreover, the risk ratios total cholesterol/HOL cholesterol and LOL cholesterol/HOL cholesterol were significantly higher, and the ratio ApoA1/ApoB was significantly lower in both groups of patients in comparison to the normal subjects. Both groups of dialysis patients exhibited decreased ratios of LOL cholesterol/ApoB and HOL cholesterol/ApoAI, suggesting the presence of compositional lipoprotein changes. CAPO patients had a more atherogenic lipid profile compared to HO patients, since they exhibited higher levels of total and LOL cholesterol, of ApoB as well as of the ratios total cholesterol/HOL cholesterol and LOL cholesterol/ HOL cholesterol, and lower levels of the ratio ApoA1/ApoB compared to HO patients. Both groups of dialysis patients had increased serum Lp(a) levels. Even though CAPO patients had higher serum Lp(a) levels than HO patients, the differences between these two groups were only marginally statistically significant (p = 0.056 by Mann-Whitney U-test). Uremic dyslipidemia was positively correlated with serum albumin levels in both groups of patients.

Conclusion

CAPO patients exhibit a more atherogenic lipid profile than that of HO patients. The marked disturbances in Lp(a) levels may further increase the vascular risk in both groups of patients.

Fibrinogen and Fibrinolytic Activity in Capd Patients with Atherosclerosis and Its Correlation with Serum Albumin

Objective

It has been suggested that hypoalbuminemia in dialysis patients leads to a hypercoagulable state, however, the relationship between serum albumin and fibrinogen or fibrinolytic activity has not been well-documented. The aim of this study was to investigate the changes of fibrinogen, tissue plasminogen activator (tPA), plasminogen activator inhibitor type-1 (PAI-1), and lipid levels in continuous ambulatory peritoneal dialysis (CAPD) patients with atherosclerosis, and the relationship between those factors and serum albumin.

Design

A cross-sectional study.

Setting

A university hospital.

Patients

Twenty CAPD patients with atherosclerosis, 49 CAPD patients without atherosclerosis, and 33 normal controls were included. Presence of atherosclerosis was determined by positive results in a stress thallium singlephoton emission computed tomography or an ankle brachial index less than 0.9. Coronary angiography and/ or Doppler ultrasound of extremities were followed for the patients with positive results to confirm atherosclerotic cardiovascular disease.

Main outcome measures

tPA and PAI-1 levels were determined with ELISA method, and fibrinogen with thrombin time method. Serum albumin and lipids were also measured.

Results

Serum albumin and HDL -cholesterol levels were significantly lower, and the ratio of total cholesterol/ HDL was significantly higher, in CAPD patients than in normal controls. CAPD patients with atherosclerosis had significantly higher fibrinogen, tPA, and PAI-levels than other groups. tPA was an independent predictor of atherosclerotic vascular disease in CAPD patients in stepwise logistic regression analysis. Serum albumin level was inversely correlated with fibrinogen (r = -0.28; p < 0.05) in CAPD patients, but not with tPA or PAI-1 levels. PAI-1 level was correlated with tPA (r = 0.37; p < 0.01) and triglycerides (r = 0.32; p < 0.05).

Conclusions

Association of high levels of fibrinogen and PAI-1 with lipid disorders may be of importance in the development of atherosclerosis in CAPD patients. Hypoalbuminemia may contribute to atherosclerosis via increased synthesis of fibrinogen.

Serum C-Reactive Protein: A Predictor of Mortality in Continuous Ambulatory Peritoneal Dialysis Patients

Objective

To evaluate the predictive value of a single baseline serum C-reactive protein (sCRP) as a marker of mortality in continuous ambulatory peritoneal dialysis (CAPD) patients.

Design

A review of prospectively collected data in a 2-year follow-up study.

Setting

Tertiary medical center.

Patients

The study included 106 patients who were stable and had been on CAPD for a minimum of 3 months.

Main Outcome Measures

Patient survival rate was the main outcome measure of this study. Other outcome measures were technique survival rate, peritonitis rate, and hospitalized days. Covariables used in the survival analysis were age, sex, the presence of cardiovascular disease or diabetes mellitus, sCRP, serum albumin, hematocrit, cholesterol, HDL-cholesterol, malnutrition by subjective global assessment (SGA), weekly Kt/V urea, and weekly standardized creatinine clearance (SCCr).

Results

The 2-year patient survival rate was significantly lower in the increased sCRP group than in the normal sCRP group (66.7% vs 94.1%, p = 0.001), although there was no significant difference in technique failure, peritonitis rate, and hospitalized days between the two groups. By Cox proportional hazards analysis, independent predictors of mortality were: cardiovascular disease (relative risk, RR = 8.96, p < 0.005); increased sCRP level (RR = 1.19, p < 0.05); and high hematocrit (RR = 1.18, p < 0.05).

← Conclusion

Serum CRP at enrollment is an independent predictor of 2-year patient survival in CAPD patients.

Albumin handling in different hemodialysis modalities

Hypoalbuminemia is a major risk factor for morbidity and mortality in dialysis patients. With increasing interest in highly permeable membranes and convective therapies to improve removal of middle molecules, transmembrane albumin loss increases accordingly. Currently, the acceptable upper limit of albumin loss for extracorporeal renal replacement therapies is unknown. In theory, any additional albumin loss should be minimized because it may contribute to hypoalbuminemia and adversely affect the patient's prognosis. However, hypoalbuminemia-associated mortality may be a consequence of inflammation and malnutrition, rather than low albumin levels per se. The purpose of this review is to give an overview of albumin handling with different extracorporeal renal replacement strategies. We conclude that the acceptable upper limit of dialysis-related albumin loss remains unknown. Whether enhanced middle molecule removal outweighs the potential adverse effects of increased albumin loss with novel highly permeable membranes and convective therapies is yet to be determined.

Time-varying serum albumin levels and all-cause mortality in prevalent peritoneal dialysis patients: a 5-year observational study

BACKGROUND

In this study, we investigated the association of time-varying serum albumin levels with mortality over a 5-year period in one cohort of patients undergoing long-term peritoneal dialysis (PD) therapy.

METHODS

The participants in this study enrolled 302 patients who underwent long-term PD at a single PD center in Taiwan. We reviewed medical records from 2011 to 2015 retrospectively. Time-averaged albumin level and serum albumin reach rate (defined as the percentage of serum albumin measurements that reached ≥3.5 g/dL) were applied as the predictor variables in the first 2 years (2011-2012). All-cause mortality was used as the outcome variable in the subsequent 3 years (2013-2015). Hazard function of all-cause mortality in the study participants was examined by using Cox proportional hazard regression models .

RESULTS

Patients with different albumin reach rates (75-< 100%, 50-< 75%, 1-< 50%) did not exhibit a significantly increased risk for all-cause mortality. Patients with a 0% albumin reach rate exhibited a significantly increased risk for all-cause mortality (hazard ratio [HR] 7.59, 95% confidence interval [CI], 2.38-24.21) by fully adjusted analysis. Patients with time-averaged albumin levels of < 3.5 g/dL (HR 15.49, 95% CI 1.74-137.72) exhibited a higher risk for all-cause mortality than those with serum albumin levels ≥4.0 g/dL.

CONCLUSIONS

This study demonstrated that higher serum albumin reach rates and higher time-averaged serum albumin levels are associated with a lower mortality rate over a 5-year period among patients undergoing long-term PD.

Outcomes of Primary Arteriovenous Fistula for Hemodialysis in Elderly Patients (>65 Years) with End Stage Renal Disease: A Study on Indian Population

Introduction:

The outcome of arteriovenous fistula (AVF) for hemodialysis (HD) in elderly population remains an issue. The aim of our study was to evaluate the outcomes of arteriovenous fistulas created at our institute in patients older than 65 years.

Methods:

All chronic HD patients with age >65 years who had an AVF created between January 1, 2010 and January 1, 2017 were included retrospectively. Baseline demographic information including age, gender, etiology of renal failure and comorbidities were recorded. Access characteristics including access type and anatomic location were recorded. The end point of study was primary and secondary patency. Minimum follow up period of study was 1 year.

Results:

A total of 422 AVF were created within the study period. The mean age was 69.3 years. The anatomical site of AVF creation was radiocephalic (RCF) in 74.8% (n = 316), brachiocephalic (BCF) in 18.9% (n = 80) and brachiobasilic (BBF) in 6.1% (n = 26). At one year after creation, cumulative survival of the AVF was 64.7%. At 36 months the primary and secondary patency of RCF, BCF and BBF was 43.6%, 58.6%, 42.6% and 47.3%, 62.5%, 56.9% respectively. The overall median survival did not differ between RCF and BBF fistulas. However, when both were compared with BCF (median survival 1034 days), BBF (median survival 741 days) and RCF (median survival 592 days) had significantly poorer survival (P = 0.004). The most common reason for access failure was thrombosis (28.4%) followed by failure to mature (9%) and aneurysm related complications (9%).

Conclusions:

Age should not be a limiting factor when choosing AVF as the preferred HD access. Brachiocephalic AVF has better primary and secondary patency with higher overall median survival. However RCF also provides reasonably good survival rates with acceptable complications in elderly population. Thrombosis and fistulas that fail to mature present as a primary concern to patients in elderly population, and demand further study.

Transfusion Management of Incident Dialysis Patients in Canada: A Prospective Observational Study

Background:

Several studies have demonstrated harm associated with using erythropoiesis-stimulating agents (ESA) to achieve higher hemoglobin (Hb) levels. Subsequently, more conservative use of ESAs has changed anemia therapy in patients with chronic renal failure.

Objective:

The objectives were to identify transfusion rates in hemodialysis (HD) patients during the first year of therapy, to identify factors associated with the probability of transfusion, describe reasons for the transfusions, and identify the Hb values associated with each transfusion. An exploratory objective was to describe the age of red blood cell transfusions.

Design:

This was a multicenter prospective observational cohort study.

Setting:

There were 12 study sites in 5 Canadian provinces. The study was performed from 2012 to 2014.

Methods:

The study patients were adult incident chronic HD patients in these centers. Patients with acute kidney injury, peritoneal dialysis, and planned transfer to satellite units were excluded. Patients had to receive at least 1 month of chronic HD to be eligible. Data for 3 months prior to HD were obtained by retrospective chart review. Prospectively, charts were reviewed monthly for 12 months for data abstraction.

Results:

There were 314 patients enrolled and 79.9% completed 12 month follow-up. Ninety-four (29.9%) patients received at least 1 unit of blood. During the first 90 days, the transfusion episode rate was 148.4 per 100 patient-years compared with 62.6 per 100 patient-years post 90 days. The most frequent indication was a low Hb value (92%) with gastrointestinal bleeding, surgical blood loss, and fatigue accounting for 9.9%, 8.6%, and 4.5%, respectively. Some patients had >1 indication. The mean Hb values prior to transfusion episodes ranged from 75.3 to 78.6 g/L. Cox regression analysis on time to first transfusion and time to first hospitalization/death both showed an association with inpatient initiation of HD. Some 37.5% initiated HD as an inpatient and differed from those starting as an outpatient. They had less predialysis care and laboratory data suggested more inflammation. The mean and median ages of the blood units transfused were 24.9 (SD = 10.0) and 23 days (interquartile range = 17-33).

Conclusions:

This work reported the blood transfusion rate in incident HD patients in Canada during a period associated with conservative ESA prescription. The major indication for transfusion was a low Hb rather than clinical symptoms. Initiation of HD as an inpatient was independently associated with the probability of receiving a blood transfusion. These findings require further investigation.

Rate of bacteremia in the hemodialysis patient presenting to the emergency department with fever: a retrospective chart review

BACKGROUND

Infectious disease is the second most common cause of death in patients receiving hemodialysis (HD). When presenting to the emergency department (ED) with fever, it remains a diagnostic challenge to distinguish patients with potentially life-threatening bacterial infections from those with less significant causes of fever. The primary goal of this study was to determine the rate of bacteremia in HD patients presenting to the ED with fever. The secondary goal of this study was to identify any independent risk factors associated with bacteremia in the febrile HD patient.

METHODS

This is a retrospective medical record review of all HD patients who presented to the ED with either subjective fever as primary complaint or with a documented triage temperature of 38 °C or higher during the 3-year period between September 1, 2014, and September 1, 2017. Patient visits were included in the study if blood cultures were ordered in the ED. Data related to demographic information, clinical parameters, diagnostic test results in the ER, final diagnosis, and results of microbiology cultures were collected from each patient encounter. Univariate analysis was performed to identify risk factors associated with bacteremia.

RESULTS

We identified 353 patient visits from 138 unique patients that met inclusion criteria. Fifty-eight percent of these were women, and the average age was 54.6 years. The rate of bacteremia was 31.7%, and the main microorganisms isolated in blood culture were non-MRSA Staphylococcus aureus (40.7%), MRSA (13.3%), Pseudomonas aeruginosa (11.5%), and Enterobacter spp. (11.5%). Independent prognostic factors associated with bacteremia were use of dialysis catheter, prior history of bacteremia, and > 5% neutrophilic band cells (OR 6.55 [95% CI 3.96-10.8; p < 0.0001]; OR 8.87 [95% CI 5.32-14.8; p < 0.0001]; OR 3.32 [95% CI 1.90-5.80; p < 0.0001] respectively).

CONCLUSION

HD patients presenting to the ED with fever have high rates of bacteremia, with a significantly higher rate in patients using dialysis catheters or those with a history of bacteremia. Other clinical data available in the ED is minimally useful in predicting bacteremia.

Brachial Vein Transposition Arteriovenous Fistula: Is it an Acceptable Option for Chronic Dialysis Vascular Access?

Purpose

The aim of this study was to evaluate the midterm performance of brachial vein arteriovenous fistulas (AVFs) and to compare this performance with arteriovenous grafts (AVGs) and basilic vein transposition AVFs.

Methods

A retrospective analysis was performed. Between December 2002 and October 2006, 149 AV access procedures consisting of brachial vein transposition AVFs (11 one-stage and 2 two-stage procedures), basilic vein transposition AVFs (n=42), and AVGs (n=94) were performed in 141 patients.

Results

73% of one-stage brachial vein AVF patients experienced at least one complication during follow-up vs. 52% of the basilic vein transposition AVF group and 55% of the AVG group. The primary patency rates at 12 months for one-stage brachial vein AVFs, basilic vein AVFs, and AVGs were 24, 45 and 50%, respectively. The assisted primary patency rates were 45, 74 and 63%, and the secondary patency rates were 45, 74 and 78%, respectively. A significant difference in the overall secondary patency rates between one-stage brachial vein AVF and AVGs (p=0.015) was detected. Significance was approached between one-stage brachial vein AVFs and basilic vein AVFs overall assisted primary patency (p=0.055) and secondary patency (p=0.055) rates.

Conclusion

The brachial vein transposition, when done as a one-stage procedure, is associated with inferior patency rates when compared to the basilic vein transposition AVF and AVG. Therefore, in the setting of inadequate cephalic and basilic vein, a prosthetic graft is superior to a brachial vein transposition. A two-stage procedure, as suggested by others, may improve the results of this technique.

Creation of Secondary AV Fistulas from Failed Hemodialysis Grafts: The Role of Routine Vein Mapping

Pre-existing forearm grafts lead to dilatation of upper arm veins of the ipsilateral arm that greatly facilitates the creation of secondary arteriovenous fistulas (AVF). In this retrospective review of 18 patients, the routine and periodical revision of failed grafts were discontinued. Vein mapping by physical examination or Duplex studies was performed prior to graft failure and a secondary AVF was created when the graft failed. Using this management strategy, an AVF creation success rate of 95% was achieved despite high incidence of co-morbidity factors within the patient population. This success rate demonstrates the value of vein selection by vascular mapping prior to graft failure and early vascular access planning in the successful creation of secondary AVF.

Successful Multidisciplinary Interventions for Arterio-Venous Fistula Creation by the Pacific Northwest Renal Network 16 Vascular access Quality Improvement Program

Background

In December 2001, 44.2% of hemodialysis (HD) patients in the Northwest Renal Network (NWRN 16) received dialysis using an arteriovenous fistula (AVF). Substantial differences were noted in percentages of patients with AVF, ranging from 5% to 90% of the facility population, suggesting wide variation in physician practice patterns within the Network. To address the needs of facilities having <40% AVF, NWRN 16 provided education and tools for their vascular access decision-makers to promote AVF creation.

Methods

In 2002, the Network sponsored 4 regional workshops targeted to nephrologists, vascular surgeons, dialysis nurses, and interventional radiologists.

Results

46 facilities (43% of all Network facilities) had <40% AVF in use in December, 2001, dialyzing 2940 patients (Invited Units). Percent AVF in use in all the Invited Facilities increased from 31.3% pre-intervention to 39.8% at 1 year (p<0.001 vs pre) to 56.2% at four years: 79.8% increase in the prevalent AVF rate over a four-year period (95% confidence interval: 77.8% to 81.7%).

Conclusion

Low prevalent AVF rates in many NWRN 16 facilities may have resulted from differences in physician practice patterns. The success of Network 16 AVF Intervention demonstrates the effectiveness of Network education promoting multidisciplinary teamwork, innovative strategies to increase AVF rates among dialysis patients.

Serum LDL Levels are a Major Prognostic Factor for Arteriovenous Fistula Thrombosis (AVFT) in Hemodialysis Patients

Introduction

Arteriovenous fistula thrombosis (AVFT) is still a common cause of morbidity in patients undergoing regular hemodialysis (HD). Many factors have been found to induce AVFT. Some of those factors are local and others are systemic ones. In this study, we evaluated some local and systemic factors simultaneously, to predict the most potent risk factor for AVFT in HD patients.

Patients and methods

One hundred and eighteen patients aged 20–80 yrs with end-stage renal disease (ESRD) were evaluated prospectively for a period of 14 months. First, anticardiolipin antibodies (ACLA), TG, cholesterol, low density lipoprotein (LDL) and high density lipoprotein (HDL) were analyzed by conventional methods. Other basic data were accessed from patients' medical records. All fistulas were evaluated clinically as patent at the start of this study. Patients were followed-up for any evidence of AVFT within 14 months. Finally, all factors (diabetes, hypertension, presence of ACLA, ultrafiltration ≥3 L, age, gender, weight, hypotension during dialysis, fistula site, epoetin alpha usage, TG, HDL, LDL and total cholesterol) were analyzed in a stepwise regression analysis.

Results

Eighteen episodes of AVFT documented with Doppler sonography occurred in 17 patients (15.3%). Regression analysis showed only LDL values were the AVFT predictor in our patients (p=0.002, β-coefficient=0.3). Kaplan-Meier analysis showed a significantly lower AVF patency time in patients with LDL >130 mg/dl than those with LDL <130 mg/dl (log rank=0.0014).

Discussion

LDL value is a major prognostic factor for AVFT in HD patients and lowering it to <130 mg/dl could improve fistula patency.

Definitions and End Points for Interventional Studies for Arteriovenous Dialysis Access

This paper is part of the Clinical Trial Endpoints for Dialysis Vascular Access Project of the American Society of Nephrology Kidney Health Initiative. The purpose of this project is to promote research in vascular access by clarifying trial end points which would be best suited to inform decisions in those situations in which supportive clinical data are required. The focus of a portion of the project is directed toward arteriovenous access. There is a potential for interventional studies to be directed toward any of the events that may be associated with an arteriovenous access' evolution throughout its life cycle, which has been divided into five distinct phases. Each one of these has the potential for relatively unique problems. The first three of these correspond to three distinct stages of arteriovenous access development, each one of which has been characterized by objective direct and/or indirect criteria. These are characterized as: stage 1-patent arteriovenous access, stage 2-physiologically mature arteriovenous access, and stage 3-clinically functional arteriovenous access. Once the requirements of a stage 3-clinically functional arteriovenous access have been met, the fourth phase of its life cycle begins. This is the phase of sustained clinical use from which the arteriovenous access may move back and forth between it and the fifth phase, dysfunction. From this phase of its life cycle, the arteriovenous access requires a maintenance procedure to preserve or restore sustained clinical use. Using these definitions, clinical trial end points appropriate to the various phases that characterize the evolution of the arteriovenous access life cycle have been identified. It is anticipated that by using these definitions and potential end points, clinical trials can be designed that more closely correlate with the goals of the intervention and provide appropriate supportive data for clinical, regulatory, and coverage decisions.

The Brachio-Brachial Arteriovenous Fistula: Mid-Term Results

Objective

To evaluate the mid-term results of the brachio-brachial arteriovenous fistula in patients without adequate superficial venous circulation in the upper limb.

Methods

Retrospective analysis included 49 patients, in whom a brachio-brachial fistula had been created in an end-to-side configuration. After the maturation period (1 month), the brachial vein was transposed into the subcutaneous tissue. Follow-up study was performed in patients with functional brachio-brachial fistula after the superficialization.

Results

Forty-nine patients underwent 49 brachio-brachial fistula constructions. All fistulas were functional. One month after surgery, 40 (81.6%) of these patients had a functional fistula, but in only 39 (79.6%) cases was the fistula suitable for hemodialysis (HD) following transposition to subcutaneous tissue. During the 1–month maturation period, the fistula became occluded in nine patients, and in one case the vein was permeable, so the fistula was functional, but too small to permit HD. Seventeen patients developed temporary edema of the forearm during the first month, in three cases the edema was extended to the entire arm, but no other complications were associated with the procedure. Follow-up lasted 18.0 ± 11.1 (3–37) months, during which 7/39 patients presented with fistula occlusion. Three patients died and another three were out of the study for various reasons.

Conclusions

the brachio-brachial fistula is a good alternative to prosthetic grafts in patients without superficial venous circulation in the upper limb.

The brachio-brachial arteriovenous fistula: a new method in patients without a superficial venous system in the upper limb

Purpose

This study aimed to report our experience in the creation of brachio-brachial arteriovenous fistulas (AVFs) in patients without adequate superficial venous circulation at the upper limb.

Methods

A retrospective study of 33 patients, operated on between 2004–2005, in whom we created a brachio-brachial fistula between the brachial artery and the brachial vein. After dissection and adequate mobilization, the brachial vein was anastomized to the brachial artery in an end-to-side fashion. After the maturation period (1 month) the brachial vein was transposed into the subcutaneous tissue.

Results

Thirty-three patients underwent 33 brachio-brachial fistula constructions. Primary patency was achieved in all patients. After 1 month, 27 fistulas (81.8%) were functional. Six patients developed fistula occlusion. The 27 remaining patients had subsequently good fistulas for hemodialysis (HD) afterwards. Discrete edema of the forearm was noted in 12 patients (36%); in one of these patients the edema was extended to the entire arm. No other complications were noted. A follow-up study, extended from 3–26 months (mean 14 ± 6.6 months), was performed. The overall patency rate of the brachio-brachial fistula at the end of the follow-up was 85.2%.

Conclusions

The brachio-brachial fistula can represent a viable choice in patients with an inadequate superficial venous system in the upper limb.

Arteriovenous Fistulas for Hemodialysis Created using a Long-Term Absorbable Suture: A Safe Solution and a Measure to Minimize Myointimal Hyperplasia

Background/aims

The goal of the therapeutic management of patients affected by end-stage renal disease (ESRD) is to maintain the vascular access (VA) as long as possible. Myointimal hyperplasia development in the vascular walls of arteriovenous fistulas (AVFs) is considered one of the most important factors responsible for procedure failure. These alterations could be linked to hemodynamic changes in the anastomosis and to the presence of the surgical suture itself. We report our preliminary experience, discussing the use and the possible benefits of an absorbable suture in polyglycolide trimethylene carbonate (PTC) in AVF creation.

Methods

Seventy-four AVFs were created as primary access for hemodialysis (HD), using PTC, over 4 years. Age, gender, ESRD etiology, artery and vein preoperative diameters, AVF survival outcome, and the number of AVFs created per year were recorded. The Kaplan-Meier method was used to analyze AVF survival rates.

Results

No dehiscences, pseudoaneurysms, or failures in the “critical” period related to PTC absorption were recorded. Kaplan-Meier analysis was used to evaluate AVF survival; 12-month primary AVF survival (74.33%) and AVF failure (25.67%) rates, 9 “early” (8.22%) and 10 “late” failures (13.51%), and a 360-day mean survival were found.

Conclusions

Our data indicate that PTC, a well known and widely used material for sutures in vascular surgery, is safe and effective in AVF creation. Potential advantages of PTC sutures are represented by a reduced myointimal hyperplasia formation in the AVF vascular walls, prolonging the AVF lifespan and avoiding re-interventions.

Maturation of arteriovenous fistula: Analysis of key factors

The growing proportion of individuals suffering from chronic kidney disease has considerable repercussions for both kidney specialists and primary care. Progressive and permanent renal failure is most frequently treated with hemodialysis. The efficiency of hemodialysis treatment relies on the functional status of vascular access. Determining the type of vascular access has prime significance for maximizing successful maturation of a fistula and avoiding surgical revision. Despite the frequency of arteriovenous fistula procedures, there are no consistent criteria applied before creation of arteriovenous fistulae. Increased prevalence and use of arteriovenous fistulae would result if there were reliable criteria to assess which arteriovenous fistulae are more likely to reach maturity without additional procedures. Published studies assessing the predictive markers of fistula maturation vary to a great extent with regard to definitions, design, study size, patient sample, and clinical factors. As a result, surgeons and specialists must decide which possible risk factors are most likely to occur, as well as which parameters to employ when evaluating the success rate of fistula development in patients awaiting the creation of permanent access. The purpose of this literature review is to discuss the role of patient factors and blood markers in the development of arteriovenous fistulae.

Impact of risk factors on functional status in maintenance hemodialysis patients

Objectives

To survey by measuring patient’s functional status which is crucial when end-stage renal disease patients begin a dialysis program. The influence of the disease on patients can be examined by the measurement of Karnofsky Performance Status (KPS) scores, together with a quality of life survey, and clinical variables.

Methods

The details for the dataset in the study were collected from patients receiving regular hemodialysis (HD) in one hospital, which were available retrospectively for 1166 patients during the 5-year study period. KPS scores were applied for quantifying functional status. To identify risk factors for functional status, clinical factors including demographics, laboratory data, and HD vintage were selected. This study applied a classification and regression tree approach (CART) and logistic regression to determine risk factors on functional impairment among HD patients.

Results

Ten risk factors were identified by CART and regression model (age, primary kidney disease subclass, treatment years, hemoglobin, albumin, creatinine, phosphorus, intact parathyroid hormone, ferritin, and cardiothoracic ratio). The results of logistic regression with selected interaction models showed older age or higher hematocrit, blood urea nitrogen, and glucose levels could significantly increase the log-odds of obtaining low KPS scores at in-person visits.

Conclusions

In interaction results, the combination of older age with higher albumin level and higher creatinine level with longer HD treatment years could significantly decrease the log-odds of a low KPS score assessment during in-person visits. Age, hemoglobin, albumin, urea, creatinine levels, primary kidney disease subclass, and HD duration are the major determinants for functional status in HD patients.

Electronic supplementary material

The online version of this article (10.1186/s40001-017-0298-1) contains supplementary material, which is available to authorized users.

[Initiating hemodialysis in Morocco: Impact of late referral]

INTRODUCTION

End-stage renal disease (ESRD) is a major public health concern in Morocco with an incidence in constant progression according to MAGREDIAL "Morocco Dialysis Registry". Patients are often sent late to nephrologists, which is a source of complications recognized in several countries. For these reasons, we tried to evaluate, in our context, the prevalence and factors of this late referral (LR).

METHODS

This is a retrospective study which included all patients initiating hemodialysis between January 2007 and December 2015. We found the history of following these patients and sought their clinical characteristics at the time of setting hemodialysis.

RESULTS

During the study, 318 patients were admitted for management of ESRD. Their average age was 54.31 years and diabetic nephropathy was the most common cause of 41% of cases. Only 105 patients (33%) had a nephrological follw up in almost two thirds of cases, hemodialysis was started by using a temporary central venous catheter especially femoral. we have identified five factors associated with LR: nemia, hypoalbuminemia, inflammatory syndrome, a longer initial hospitalization, a greater use of temporary catheterization as first access.

CONCLUSION

LR patients with ESRD remains very common in our context. It is about 67% and complicates implementation hemodialysis patients with anemia and more use of central catheters that are predictors of mortality previously described in the literature. Economically, LR significantly increases the cost of care by significantly increasing the duration of hospitalization.

Comparison of Post-Creation Procedures and Costs between Surgical and an Endovascular Approach to Arteriovenous Fistula Creation

Introduction

Due to early and late failures that may occur with surgically created hemodialysis arteriovenous fistulas (SAVF), post-creation procedures are commonly required to facilitate AVF maturation and maintain patency. This study compared AVF post-creation procedures and their associated costs in patients with SAVF to patients with a new endovascularly created AVF (endoAVF).

Methods

A 5% random sample from Medicare Standard Analytical Files was abstracted to determine post- creation procedures and associated costs for SAVF created from 2011 to 2013. Medicare enrollment during the 6 months prior to and after the AVF creation was required. Patients’ follow-up inpatient, outpatient, and physician claims were used to identify post-creation procedures and to estimate average procedure costs. Comparative procedural information on endoAVF was obtained from the Novel Endovascular Access Trial (NEAT).

Results

Of 3764 Medicare SAVF patients, 60 successfully matched to endoAVF patients using 1:1 propensity score matching of baseline demographic and clinical characteristics. The total post-creation procedural event rate within 1 year was lower for endoAVF patients (0.59 per patient-year) compared to the matched SAVF cohort (3.43 per patient-year; p<0.05). In the endoAVF cohort, event rates of angioplasty, thrombectomy, revision, catheter placement, subsequent arteriovenous graft (AVG), new SAVF, and vascular access-related infection were all significantly lower than in the SAVF cohort. The average first year cost per patient-year associated with post-creation procedures was estimated at US$11,240 USD lower for endoAVF than for SAVF.

Conclusions

Compared to patients with SAVF, patients with endoAVF required fewer post-creation procedures and had lower associated mean costs within the first year.

Clinical Utility of a New Predicting Score for Radiocephalic Arteriovenous Fistula Survival

BACKGROUND

Radiocephalic arteriovenous fistula (RC-AVF) is the recommended first choice for vascular access (VA). The CAVeA₂T₂ scoring system was recently published (ipsilateral central venous catheter access, age >73 years, vein <2.2 mm, lower limb angioplasty, and absent intraoperative thrill). The aim of the present study was to assess the clinical utility of the CAVeA₂T₂ scoring system for predicting RC-AVFs survival in our center and its subsequent application in VA management.

MATERIAL AND METHODS

In this single-center retrospective study, all RC-AVFs performed from January 2010 to July 2014 were included. The CAVeA₂T₂ was applied. Primary, assisted primary, and secondary patency rates were measured.

RESULTS

Sixty RC-AVFs were analyzed. Mean age was 64.3 ± 14.7 years. Mean CAVeA₂T₂ score was 1.23 ± 1.2. The median fistula secondary patency was 13.7 ± 1.6 months. Secondary patency was at 6 weeks and at 6, 12, and 24 months: 88.3%, 66.7%, 55%, and 31.7%, respectively. Increasing score (≥2) was associated with a decrease in primary (log-rank, χ² = 16.7, dif = 1, P = 0.0001) and secondary patency rate survival (log-rank, χ² = 5.4, dif = 1, P = 0.0001). In addition, stratification of the CAVeA₂T₂ score into 3 groups (scores 0-1, 2, and 3+) retained its significance for primary (log-rank, χ² = 19.4, dif = 2, P = 0.0001) and secondary patency rate survival (log-rank, χ² = 5.5, dif = 2, P = 0.046) at the end of the study.

CONCLUSIONS

In the present study, the CAVeA₂T₂ scoring system has proved to be a useful, easy to apply tool that is highly predictive of RC-AVF survival. Based on our results, we should avoid perform RC-AVFs, in those patients with CAVeA₂T₂ score ≥2 and late nephrology referral. Prospective studies should be designed to establish the management of patients with a higher CAVeA₂T₂ score.

An Increase in Mean Platelet Volume/Platelet Count Ratio Is Associated with Vascular Access Failure in Hemodialysis Patients

After stenosis of arteriovenous vascular access in hemodialysis patients, platelets play a crucial role in subsequent thrombus formation, leading to access failure. In a previous study, the mean platelet volume (MPV)/platelet count ratio, but not MPV alone, was shown to be an independent predictor of 4-year mortality after myocardial infarction. However, little is known about the potential influence of MPV/platelet count ratio on vascular access patency in hemodialysis patients. A total of 143 patients undergoing routine hemodialysis were recruited between January 2013 and February 2016. Vascular access failure (VAF) was defined as thrombosis or a decrease of greater than 50% of normal vessel diameter, requiring either surgical revision or percutaneous transluminal angioplasty. Cox proportional hazards model analysis ascertained that the change of MPV/platelet count ratio between baseline and 3 months [Δ(MPV/platelet count ratio)_3mo-baseline] had prognostic value for VAF. Additionally, the changes of MPV/platelet count ratio over time were compared in patients with and without VAF by using linear mixed model analysis. Of the 143 patients, 38 (26.6%) were diagnosed with VAF. During a median follow-up of 26.9 months (interquartile range 13.0–36.0 months), Δ(MPV/platelet count ratio)_3mo-baseline significantly increased in patients with VAF compared to that in patients without VAF [11.6 (6.3–19.0) vs. 0.8 (-1.8–4.0), P< 0.001]. In multivariate analysis, Δ(MPV/platelet ratio count)_3mo-baseline was an independent predictor of VAF, after adjusting for age, sex, diabetes, hypertension, coronary artery disease, cerebrovascular disease, vascular access type, the presence of previous VAF, and antiplatelet drug use (hazard ratio, 1.15; 95% confidence interval, 1.10–1.21; P< 0.001). Moreover, a liner mixed model revealed that there was a significant increase of MPV/platelet count ratio over time in patients with VAF compared to those without VAF (P< 0.001). An increase in MPV/platelet count ratio over time was an independent risk factor for VAF. Therefore, continuous monitoring of the MPV/platelet count ratio may be useful to screen the risk of VAF in patients undergoing routine hemodialysis.

The Type of Vascular Access and the Incidence of Mortality in Japanese Dialysis Patients

Objective The National Kidney Foundation (NKF) Kidney Disease Outcome Quality Initiative (KDOQI) guidelines have recommended the use of arteriovenous fistula (AVF) at the initiation of dialysis. However, there are significant differences in the dialysis environments of Japan and the United States, and there are few people who receive hemodialysis via a central venous catheter (CVC) in Japan. The aim of the present study was to examine the association between the type of vascular access at the initiation of dialysis and the incidence of mortality in Japan. Methods This study was a prospective, multicenter, cohort study. The data was collected by the Aichi Cohort study of Prognosis in Patients newly initiated into dialysis (AICOPP) in which 18 Japanese tertiary care centers participated. The present study enrolled 1,524 patients who were newly introduced to dialysis (the patients started maintenance dialysis between October 2011 and September 2013). After excluding 183 patients with missing data, 1,341 patients were enrolled. The Cox proportional hazards model was used to evaluate mortality based on the type of vascular access. The types of vascular access were divided into four categories: AVF, arteriovenous graft (AVG), CVC changed to AVF during the course (CAVF), CVC changed to AVG during the course (CAVG). Results A multivariate analysis revealed that AVG, CAVF and CAVG were associated with a higher risk of mortality in comparison to AVF [hazard ratio (HR), 1.60; p=0.048; HR, 2.26; p=0.003; and HR, 2.45; p=0.001, respectively]. Conclusion The research proved that the survival rate among patients in whom hemodialysis was initiated with AVF was significantly higher than that in patients in whom hemodialysis was initiated with AVG or CVC.

Epoetin Alfa and Outcomes in Dialysis amid Regulatory and Payment Reform

Erythropoiesis-stimulating agents (ESAs) are commonly used to treat anemia in patients with CKD, including those receiving dialysis, although clinical trials have identified risks associated with ESA use. We evaluated the effects of changes in dialysis payment policies and product labeling instituted in 2011 on mortality and major cardiovascular events across the United States dialysis population in an open cohort study of patients on dialysis from January 1, 2005, through December 31, 2012, with Medicare as primary payer. We compared observed rates of death and major cardiovascular events in 2011 and 2012 with expected rates calculated on the basis of rates in 2005-2010, accounting for differences in patient characteristics and influenza virulence. An abrupt decline in erythropoietin dosing and hemoglobin concentration began in late 2010. Observed rates of all-cause mortality, cardiovascular mortality, and myocardial infarction in 2011 and 2012 were consistent with expected rates. During 2012, observed rates of stroke, venous thromboembolic disease (VTE), and heart failure were lower than expected (absolute deviation from trend per 100 patient-years [95% confidence interval]: -0.24 [-0.08 to -0.37] for stroke, -2.43 [-1.35 to -3.70] for VTE, and -0.77 [-0.28 to -1.27] for heart failure), although non-ESA-related changes in practice and Medicare payment penalties for rehospitalization may have confounded the results. This initial evidence suggests that action taken to mitigate risks associated with ESA use and changes in payment policy did not result in a relative increase in death or major cardiovascular events and may reflect improvements in stroke, VTE, and heart failure.

An association between time-varying serum albumin level and the mortality rate in maintenance haemodialysis patients: a five-year clinical cohort study

BACKGROUND

Until now, no long-term studies relating serum albumin level to mortality rate in prevalent haemodialysis (HD) patients have been conducted. We aimed to examine the association between serum albumin level and mortality over a 5-year period.

METHODS

This study included 781 patients who received maintenance HD in a large, hospital-facilitated HD centre. Five-year medical records (2009-2013) were retrospectively reviewed, and the cut-off level for serum albumin level was set at 3.5 g/dL. The analysed albumin levels were expressed as time-averaged levels (first 24-month data) and albumin target reach rate over the first 2-year interval. Univariate and multivariate Cox proportional hazard regression models were used to examine the hazard function of the all-cause and cardiovascular mortality of the study participants in the subsequent 3-year period (2011-2013).

RESULTS

Compared to those with a 100 % albumin reach rate (3.5 g/dL), the participants with 75- < 100, 50- < 75, and 1- < 50 % albumin reach rates exhibited significantly increased risk for all-cause mortality (HR 1.72, 95 % CI 1.19-2.47; HR 3.14, 95 % CI 1.91-5.16; HR 3.66, 95 % CI 2.18-6.16, respectively). A similar trend for all-cause mortality was demonstrated in participants with time-averaged albumin levels <4 g/dL (HR 1.57, 95 % CI 1.00-2.46 for 3.5-4.0 g/dL; HR 3.66, 95 % CI 2.11-6.32 for <3.5 g/dL). Compared to a 100 % albumin reach rate, the 50- < 75 and 1- < 50 % groups (HR 4.28, 95 % CI 1.82-10.01; HR 3.23, 95 % CI 1.22-8.54 respectively) showed significantly higher cardiovascular mortality rates. Similarly, participants with a time-averaged serum albumin level <3.5 g/dL exhibited a higher risk for cardiovascular mortality (HR 3.24, 95 % CI: 1.23-8.56).

CONCLUSIONS

This long-term study demonstrated that higher reach rates of serum albumin levels and higher time-averaged serum albumin levels are associated with a lower mortality rate in patients undergoing maintenance HD.

Subcutaneous Transposition of Arterialized Upper Arm Veins for Hemodialysis Angioaccess: Optimal Alternative to Grafts

The authors report 42 subcutaneous transpositions of arterialized deep upper arm veins for hemodialysis angioaccess: 37 basilic (BaF) and 5 brachial (BrF) fistulas, done in 38 patients, 18 of them diabetics, with local anesthesia. Indications for BaF and BrF creation were surgically exhausted forearm veins and/or severe arteriosclerotic changes of distal arteries. No neurologic or circulatory complications were seen. Cumulative patency rates for all fistulas was 100% at the first month and 82% one year after surgery. BaF and BrF are optimal autogenous alternatives to synthetic grafts.

Factors associated with early mortality in haemodialysis patients undergoing coronary artery bypass surgery

Introduction:

Coronary artery bypass grafting (CABG) results in higher morbidity and mortality rates in end-stage renal disease (ESRD) patient populations than in patients with normal renal function. This study aimed to identify the early results of CABG performed on ESRD patients, and the factors that affected the mortality rates of those patients.

Methods:

A retrospective evaluation of our hospital database revealed 84 haemodialysis-receiving patients who underwent CABG during the years 2006 to 2012. Mortality was observed in 21 patients (group 1), and this group was compared with the remaining patients (group 2) for peri-operative parameters such as age, EuroSCORE, functional capacity, myocardial infarction, use of inotropes and completeness of revascularisation.

Results:

The study included 60 male (71.4%) and 24 female patients (28.6%); the participants’ mean age was 59.50 ± 9.93 years. The pre-operative additive EuroSCORE was 7.96 ± 2.88 (range: 2–18). Pre-operative functional capacity was impaired in 35.7% of the patients [New York Heart Association (NYHA) classes III–IV]. Mean age and preoperative EuroSCORE values of group 1 were significantly higher than those of group 2. Impaired functional capacity (NHYA classes III–IV) was also associated with mortality (OR: 3.333; 95% CI: 1.199–9.268).

Fifty-four patients (64.3%) underwent on-pump CABG procedures, and 30 (35.7%) underwent off-pump CABG procedures. The study found no statistically significant difference in mortality rates between these two techniques. Mortality occurred in 12 patients (22.2%) in the on-pump group and in nine (30%) in the off-pump group. Complete revascularisation was performed on 46 patients (85.2%) in the on-pump group and seven (23.3%) in the off-pump group (p < 0.001).

Conclusion

Advanced age, impaired NYHA functional capacity and pre-operative hypertension were determinative for early-term surgical mortality. An on-pump surgical technique is recommended to ensure completeness of revascularisation.

Design of the fish oil inhibition of stenosis in hemodialysis grafts (FISH) study

Background Arteriovenous grafts (AVG) are the predominant form of permanent vascular access used among hemodialysis (HD) patients in North America but suffer from high intervention and complication rates associated with vascular stenosis. The fish oil inhibition of stenosis in hemodialysis grafts (FISH) study evaluates the efficacy of fish oil in improving HD graft patency.

Methods This study is a multi-center, randomized, double blind placebo-controlled clinical trial of 232 chronic HD patients who require a new graft access. Participants are randomized to fish oil versus placebo post-operatively. The primary endpoint is the proportion of AVG with loss of native patency within 12 months of creation. Secondary endpoints are aimed to determine the effect of fish oil on factors that may promote stenosis and thrombosis. Cumulative patency rates, survival analysis, and analysis of inflammatory markers and adverse events will provide a better understanding of the potential effect of fish oil on a patient's vascular access and cardiovascular system. The FISH study is registered at current controlled trials (www.controlled-trials.com) ISRCTN: 15838383.

Results Details of the study protocol are described including mechanisms of reducing bias through randomization and double blinding, sample size determination, evaluation of patient adherence, access monitoring, and the safety of using fish oil. The main challenges of designing and implementing this study, including using a natural supplement as an intervention in modern medical practice and recruitment of graft recipients in the `fistula first' environment are discussed. Conclusion This is the first large, multicenter, randomized controlled trial of a natural supplement in preventing HD graft stenosis and thrombosis. Clinical Trials 2007; 4: 357—367. http://ctj.sagepub.com

Medical Adjuvant Treatment to Improve the Patency of Arteriovenous Fistulae and Grafts: A Systematic Review and Meta-analysis

BACKGROUND

Many patients using haemodialysis for end-stage renal disease (ESRD) require arteriovenous fistulae (AVF) or grafts. Patency can be variable, and this systematic review aimed to determine the effects of adjuvant drug treatment on the patency of AVFs and grafts.

METHODS

The Cochrane Peripheral Vascular Diseases Group searched the Specialised Register and CENTRAL for all randomised controlled trials (RCTs) investigating the effect of active drug versus placebo on patency. The primary outcome was fistula or graft patency rate. The odds ratio (OR) was used as the measure of effect for each outcome. If several trials assessed the same adjuvant therapy then a meta-analysis was conducted using a Mantel-Haenszel model.

RESULTS

Fifteen trials were deemed suitable for inclusion, investigating nine drug treatments in 2,230 participants. Overall, the quality of evidence was low. Three trials compared ticlopidine (a platelet aggregation inhibitor) versus placebo and favoured active treatment (OR 0.45, 95% CI 0.25 to 0.82; p = .009). Three RCTs assessed aspirin versus placebo and did not show a statistical benefit (OR 0.40, 95% CI 0.07-2.25; p = .30). Two trials compared clopidogrel with placebo. The overall result did not favour treatment (OR 0.40, 95% CI 0.13 to 1.19; p = .10). Three trials evaluated human type-I pancreatic elastase but did not provide evidence of improved patency (OR 0.75, 95% CI 0.42-1.32; p = .31). Finally, two RCTs assessed fish oil and did not favour treatment (OR 0.24, 95% CI 0.03-1.95; p = .18). Single trials comparing dipyridamole alone, dipyridamole plus aspirin, and sulfinpyrazone against placebo favoured active treatment but a meta-analysis could not be undertaken. Finally, a single trial of warfarin versus placebo found warfarin resulted in increased complications and worse patency rates.

CONCLUSION

This systematic review has not demonstrated a beneficial effect for any adjuvant treatment to increase the patency of AVF or grafts in the short term, except ticlopidine which has been taken off the market.