Associations between hemodialysis access type and clinical outcomes: a systematic review

Anatomical Feasibility of Percutaneous Arteriovenous Fistula Formation in Korea

INTRODUCTION

Currently, there are two types of percutaneous arteriovenous fistula (pAVF) formation systems approved by the FDA: Ellipsys and WavelinQ. Although these systems are already in use in Europe or the United States, they have not been approved for use in Korea yet. For this reason, this study aimed to check anatomical feasibility of these systems for Korean population prior to their actual use.

METHODS

Consecutive patients who received ultrasound vein mapping for arteriovenous fistula formation from June 2021 to June 2022 were included. The anatomical feasibility of each system was confirmed according to the manufacturer's instructions for use (IFU).

RESULTS

Upper extremity ultrasonography was performed for a total of 83 patients to determine their feasibility for pAVF formation. Of these patients, 65.1% were feasible for pAVF formation with appropriate deep communicating vein (DCV) and outflow. Among them, 57.8% were feasible for the Ellipsys system and 54.2% were feasible for the WavelinQ system. Most patients who were infeasible for pAVF formation had a DCV of small size. Ulnar vessels were more suitable than radial vessel for WavelinQ (54.2% vs 33.7%, P-value = .012). The most common reason for not meeting the criteria was a small vein size at the access site.

CONCLUSIONS

More than half of all patients were feasible for pAVF formation in this study. Ellipsys had a higher feasibility than WavelinQ, although they showed no significant difference in the feasibility. If these devices are imported into Korea, it will be a good opportunity for many patients to reduce the surgical burden and create AVFs more easily through these procedures.

Development of a bleeding arteriovenous fistula task trainer

BACKGROUND

As end-stage renal disease becomes more prevalent in the United States, the number of Americans with arteriovenous (AV) fistulas continues to increase. One of the most feared complications of AV fistulas is life-threatening hemorrhage, as patients can exsanguinate within minutes.

OBJECTIVES

As frontline healthcare workers, emergency medicine (EM) providers need to be able to provide rapid and effective treatment for this rare presentation. We developed a task trainer model to simulate AV fistula hemorrhage to prepare and train EM residents.

METHODS

This task trainer model was constructed with readily available materials and takes about 30 minutes to make. Twenty-one EM residents participated in the training session. The session consisted of a brief didactic on AV fistula hemorrhage control followed by hands on usage of the task-trainer model. The participants filled out an anonymous survey afterwards rating the model.

RESULTS

Residents completed anonymous postcourse surveys rating the session on a five-point Likert scale. Both the overall teaching session and the task trainer were rated very highly. Compared to precourse ratings, residents reported statistically significant postcourse improvements in their level of confidence in managing AV fistula hemorrhage.

CONCLUSIONS

To our knowledge, this is the first published task trainer model to simulate a bleeding AV fistula for EM residents. The model was well received by our trainees, is relatively inexpensive, and made from easily sourced materials. We believe this model can be used for trainees of all disciplines to prepare them for this potentially catastrophic patient presentation.

Dialysis for Chronic Kidney Failure: A Review

Importance

More than 3.5 million people worldwide and 540 000 individuals in the US receive maintenance hemodialysis or peritoneal dialysis for the treatment of chronic kidney failure. The 5-year survival rate is approximately 40% after initiation of maintenance dialysis.

Observations

Hemodialysis and peritoneal dialysis remove metabolic waste and excess body water and rebalance electrolytes to sustain life. There is no recommended estimated glomerular filtration rate (eGFR) threshold for initiating dialysis, and patient-clinician shared decision-making should help determine when to initiate dialysis. Persistent signs and symptoms of uremia (eg, nausea, fatigue) and volume overload (eg, dyspnea, peripheral edema), worsening eGFR, metabolic acidosis, and hyperkalemia inform the timing of therapy initiation. A randomized clinical trial reported no mortality benefit to starting dialysis at higher eGFR (10-14 mL/min/1.73 m2) vs lower eGFR (5-7 mL/min/1.73 m2) levels. Observational data suggested no differences in 5-year mortality with use of hemodialysis vs peritoneal dialysis. Cardiovascular (eg, arrhythmias, cardiac arrest) and infection-related complications of maintenance dialysis are common. In the US, hemodialysis catheter-related bloodstream infections occur at a rate of 1.1 to 5.5 episodes per 1000 catheter-days and affect approximately 50% of patients within 6 months of catheter placement. Peritonitis occurs at a rate of 0.26 episodes per patient-year and affects about 30% of individuals in the first year of peritoneal dialysis therapy. Chronic kidney failure-related systemic complications, such as anemia, hyperphosphatemia, hypocalcemia, and hypertension, often require pharmacologic treatment. Hypotension during dialysis, refractory symptoms (eg, muscle cramps, itching), and malfunction of dialysis access can interfere with delivery of dialysis.

Conclusions and Relevance

In 2021, more than 540 000 patients in the US received maintenance hemodialysis or peritoneal dialysis for treatment of chronic kidney failure. Five-year survival rate after initiation of maintenance dialysis is approximately 40%, and the mortality rate is similar with hemodialysis and peritoneal dialysis. Decisions about dialysis initiation timing and modality are influenced by patient symptoms, laboratory trajectories, patient preferences, and therapy cost and availability and should include shared decision-making.

The Broader Effects of Delayed Progression to End-Stage Kidney Disease: Delaying the Inevitable or a Meaningful Change?

A global rise in the prevalence of patients with chronic kidney disease (CKD) with end-stage kidney disease (ESKD) has led to a considerable and increasing burden to health systems, patients, and society. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are proven to reduce incidence of cardio-renal outcomes, including onset of ESKD. Recent post hoc analyses of SGLT2 inhibitor trials extrapolate substantial delays in the average time to ESKD over a patient's lifetime. In this article, we explore the possible real-world effects of such a delay by considering the available evidence reporting outcomes following onset of ESKD. From the patient perspective, a delay in reaching ESKD could substantially improve health-related quality of life and result in additional life years without the need for kidney replacement therapies, a target relevant to all CKD subpopulations. Furthermore, should a patient initiate dialysis at an older age as a result of CKD progression, the time spent in receipt of dialysis, and therefore associated healthcare costs, may also be reduced. A delay in progression may also lead to changes in the management of ESKD, such as increased election of conservative care in preference to dialysis, particularly in elderly populations. For younger patients with CKD, those who reach ESKD while employed face considerable work impairment and productivity loss, as may families and care partners of working age. Therefore, a delay to the onset of ESKD will reduce the proportion of their working lives affected by productivity losses or unemployment due to medical reasons. In conclusion, optimised treatment of CKD may lead to a shift in treatment options, but proper and timely implementation is essential for the realisation of improved outcomes.

Association of the panimmune-inflammatory value (PIV) with all-cause and cardiovascular mortality in maintenance hemodialysis patients: a propensity score matching retrospective study

PURPOSE

The panimmune-inflammatory value (PIV) is a novel inflammatory indicator. However, its role in maintenance hemodialysis (MHD) remains unclear. Our goal was to explore the predictive value of PIV for cardiovascular and all-cause mortality in MHD patients.

METHODS

In this retrospective cohort study, 507 patients receiving MHD between November 2017 and December 2022 were enrolled. The PIV value was calculated as follows: neutrophil count × monocyte count × platelet count/lymphocyte count. Patients were divided into two groups on the basis of the median PIV. Propensity score matching (PSM) was used to adjust for imbalances in baseline information between groups. Kaplan‒Meier curves, Cox regression, the Fine‒Gray competing risk model, and restricted cubic spline (RCS) curves were used to analyze the relationship between PIV and mortality.

RESULTS

By the end of follow-up, 126 deaths had occurred, 91 of which were due to cardiovascular disease. The Kaplan‒Meier curves demonstrated that MHD patients with higher PIV levels had a poorer prognosis for all-cause death (p = 0.019). PIV levels were linked to all-cause death in multivariate Cox proportional risk regression (HR = 1.76; 95% CI 1.14, 2.72; p = 0.011). The Fine‒Gray model revealed a greater cumulative incidence of cardiovascular death in the higher PIV group (p = 0.035). PIV levels were linked to cardiovascular mortality in the Fine‒Gray competing risk model (HR = 2.06; 95% CI 1.25, 3.42; p = 0.005). The RCS revealed a nonlinear relationship between PIV and mortality risk (p < 0.05). Using 63 years of age as the threshold, we observed a multiplicative interaction effect between age and PIV for all-cause mortality (p = 0.006).

CONCLUSION

In MHD patients, PIV is an independent hazard factor for cardiovascular-related mortality and all-cause mortality.

Validation of arteriovenous access stage (AVAS) classification: a prospective, international multicentre study

Background

The arteriovenous access stage (AVAS) classification provides evaluation of upper extremity vessels for vascular access (VA) suitability. It divides patients into classes within three main groups: suitable for native fistula (AVAS1) or prosthetic graft (AVAS2), and patients not suitable for conventional native or prosthetic VA (AVAS3). We validated this system on a prospective dataset.

Methods

A prospective, international observational study (NCT04796558) involved 11 centres from 8 countries. Patient recruitment was from March 2021 to January 2024. Demographic data, risk factors, vessels parameters, VA types, AVAS class and early VA failure were collected. Percentage agreement was used to assess predictive ability of AVAS (comparison of AVAS and created VA) and consistency of AVAS assessment between evaluators. Pearson's Chi-squared test was used for comparison of early failure rate of conventional (predicted by AVAS) and unconventional (not predicted by AVAS) VA.

Results

From 1034 enrolled patients, 935 had arteriovenous fistula or graft, 99 patients did not undergo VA creation due opting for alternative renal replacement therapies, experiencing health complications, death or non-compliance. AVAS1 had 91.2%, AVAS2 7.2% and AVAS3 1.6% of patients. Agreement between evaluators was 89%. The most frequently created VAs were radial-cephalic (46%) and brachial-cephalic (27%) fistulae. The accuracy of AVAS versus created access was 79%. In comparison, VA predicted by clinicians versus created access was 62.1%. Inaccuracy of AVAS prediction was more common with higher AVAS classes, and the most common reason for inaccuracy was creation of distal VA despite less favourable anatomy (17%). Patients with unconventional VA had higher early failure rate than patients with conventional VA (20% vs 9.3%, respectively, P = .002).

Conclusion

AVAS is effective in predicting VA creation, but overall accuracy is reduced at higher AVAS classes when the complexity of decision-making increases and proximal vessels require preservation. When AVAS was followed by clinicians, early failure was significantly decreased.

A Randomized Controlled Trial Comparing Automated Peritoneal Dialysis and Hemodialysis for Urgent-Start Dialysis in ESRD

Introduction

Peritoneal dialysis (PD) shows promise for urgent-start dialysis in end-stage renal disease (ESRD), with automated PD (APD) having advantages. However, there is limited multicenter randomized controlled trial (RCT) evidence comparing APD with temporary hemodialysis (HD) for this indication in China.

Methods

This multicenter RCT enrolled 116 patients with ESRD requiring urgent dialysis from 11 hospitals, randomized to APD or HD. Patients underwent a 2-week treatment with APD or HD via a temporary central venous catheter (CVC), followed by a maintenance PD. Outcomes were assessed over 12 months during 8 visits. The primary outcome was dialysis-related complications.

Results

The 1-year incidence of dialysis-related complications was significantly lower in the APD group than in the HD group (25.9% vs. 56.9%, P = 0.001). No significant differences were found between the groups in terms of PD catheter survival rates (P = 0.388), peritonitis-free survival rates (P = 0.335), and patient survival rates (P = 0.329). In terms of health economics, the total direct medical cost of the initial hospitalization for patients with ESRD was significantly lower in the APD group (27,008.39 CNY) than in the HD group (42,597.54 CNY) (P = 0.001), whereas the duration of the first hospital stay showed no significant difference (P = 0.424).

Conclusion

For patients with ESRD needing urgent initiation of dialysis, APD was associated with a lower incidence of dialysis-related complications and lower initial hospitalization costs compared with HD, with no significant differences in PD catheter survival rate, peritonitis-free survival rates, or patient survival rates. These findings can guide clinical decision-making for the optimal dialysis modality for patients requiring urgent dialysis initiation.

Outcomes of brachial artery transposition in hemodialysis patients

OBJECTIVE

In hemodialysis patients with a difficult access extremity who are not suitable for an arteriovenous fistula or arteriovenous graft creation, the concept of cannulating a superficialized artery for arterial outflow in dialysis sessions has been adopted as a tertiary alternative. However, its long-term patency and complications have not been recognized widely. We report our 16-year experience with hemodialysis access creation using the brachial artery transposition (BAT) technique.

METHODS

This single-center retrospective study included consecutive patients who underwent BAT for hemodialysis vascular access between June 1, 2006, and December 31, 2022. The patency of the whole access circuit and the transposed brachial artery itself was evaluated independently.

RESULTS

In total, 193 surgical procedures were included. The success rate was 93.2%. The mean operative time was 128 minutes. The median interval from access placement to first cannulation was 21 days. The primary patency rates for BAT were 92.3%, 91.3%, 90.3%, 86.1%, and 71.9% at 1, 2, 3, 5, and 10 years, respectively. The secondary patency rates for BAT were 96.3%, 96.3%, 95.0%, 90.1%, and 74.9% at 1, 2, 3, 5, and 10 years, respectively. The primary patency rates for the whole access circuit were 61.4%, 49.2%, 45.8%, and 26.9% at 1, 2, 3, and 5 years, respectively. The secondary patency rates for the whole access circuit were 85.1%, 83.3%, 82.0%, and 68.6% at 1, 2, 3, and 5 years, respectively. The overall patient survival rates were 79.6%, 69.6%, 54.6%, 36.5%, and 13.4% at 1, 2, 3, 5 and 10 years, respectively. The abandonments of BAT were brachial artery thrombosis (n = 6), pseudoaneurysm (n = 2), aneurysmal change (n = 1), and other reasons (n = 1). The abandonments of the whole access circuit were exhaustion of venous return (n = 26), abandonment of BAT (n = 7), and other reasons (n = 2). Complications were exhaustion of venous return (n = 26), aneurysmal change (n = 12), pseudoaneurysm (n = 6), brachial artery thrombosis (n = 7), impaired wound healing (n = 19), lymphorrhea (n = 9), skin infection (n = 5), hematoma on cannulation (n = 3), and reduced peripheral blood flow (n = 2).

CONCLUSIONS

The patency of BAT was excellent, and that of the whole access circuit was adequate, with a few complications. BAT is an effective alternative from a long-term perspective for patients who are unsuitable for conventional hemodialysis access creation.

Incidence, Risk Factors, Organism Types, and Outcomes of Catheter-Related Bloodstream Infections in Hemodialysis Patients

Background Patients undergoing hemodialysis for End-Stage Renal Disease (ESRD) are at risk for Hemodialysis Catheter-Related Bloodstream Infections (CRBSIs). This study evaluates the incidence, risk factors, organism types, and outcomes of CRBSI in adult patients on maintenance hemodialysis at King Faisal Hospital, Rwanda. Methods This was a prospective cohort study of adult patients with end-stage renal disease undergoing hemodialysis via central venous hemodialysis catheters at King Faisal Hospital, Rwanda. Upon receiving the IRB approval, 81 eligible patients, women, and men aged between 19 and 74, were enrolled. Restricted Mean Survival Time (RMST) analysis evaluated the risk factors for CRBSI. The statistical significance was determined using p-values, with a cut-off of 0.05. Results The incidence of CRBSI was found to be 0.78 episodes per 1,000 catheter-days. Acute hemodialysis catheter type and anemia were associated with increased risk for CRBSI, with a P-value less than 0.05. In addition, all CRBSI cases were due to bacteria, with 52.63% gram-negative and 47.37% gram-positive. Out of 19 CRBSI events, nine cases (47.37%) required hospitalization with a median duration of seven days. Approximately half of the CRBSIs required catheter removal. No metastatic infection or death was noted. Conclusion The present study demonstrated that our hemodialysis unit has an incidence of 0.78 episodes per 1,000 catheter-days. Catheter type and anemia were significantly associated with CRBSI.

Outcomes of balloon-assisted maturation with large-diameter balloons

OBJECTIVES

Balloon-assisted maturation (BAM) is a well-established technique for maturation of inadequate arteriovenous fistulas (AVF). The objective of this study was to evaluate outcomes of initial BAM using large-diameter angioplasty balloons.

METHODS

Charts of patients who underwent BAM between 2018 and 2021 at a single academic institution were reviewed. AVF maturation rate was the primary outcome. Secondary outcomes included procedural complications, re-intervention rates, post-procedure vein diameter, and time to catheter-free hemodialysis (HD). Outcomes of patients that underwent initial BAM with ⩾7 mm diameter balloons (Group I) were compared to those of patients that had initial BAM with <7 mm balloons (Group II).

RESULTS

Group I (n = 149) was a significantly younger cohort and had more men compared to Group II (n = 90). There were no significant differences associated with procedural details and complication rates. Median vein diameter was larger (5.9 mm, IQR: 5-6.4) in Group I compared to Group II (5.1 mm, IQR: 4.2-5.9; p = 0.03) on post-procedure Duplex ultrasound. There was also a higher incidence of vein stenosis in Group II. The overall maturation rate was higher in Group I (97% vs 88%, p = 0.003), and a larger proportion of patients in Group II required more than one BAM to achieve maturation (33% vs 16%, p = 0.002). The median time to catheter-free HD after first BAM was 29 days (IQR: 19-47) in Group I and 42 days (IQR: 24-75) in Group II (p = 0.002). At 60 days after first BAM, the incidence of catheter-free HD was 83% in Group I versus 67% in Group II (p = 0.001).

CONCLUSIONS

Our study demonstrates that the ability to utilize large angioplasty balloons during initial BAM is associated with higher rates of AVF maturation with fewer re-interventions and shorter time to catheter-free dialysis. AVFs that can tolerate this procedure often have more favorable baseline characteristics.

Development of an investigation form for hemodialysis infection outbreak: Identifying sources in the early stage

BACKGROUND

There are many infectious factors causing the outbreak of hemodialysis infection, which may easily lead to the delay of investigation and treatment. This study aimed to develop an investigation form for hemodialysis infection outbreak (HIO), and to identify sources of outbreak in early stage.

METHODS

After an exhaustive literature review, we used the Delphi method to determine the indicators and relative risk scores of the assessment tools through 2 rounds of specialist consultation and overall consideration of the opinions and suggestions of 18 specialists.

RESULTS

A total of 87 studies of HIOs were eligible for inclusion. The mean authority coefficient (Cr) was 0.89. Kendall's W coefficient of the specialist consultation was 0.359 after 2 rounds of consultation (P < .005), suggesting that the specialists had similar opinions. Based on 4 primary items and 13 secondary items of the source of HIO, and tripartite distribution characteristics of infected patients, we constructed the investigation form.

CONCLUSIONS

The investigation form may be implemented during the initial phase of an outbreak investigation, it is a prerequisite for taking effective control measures, avoiding HIO occurrence. However, the efficacy of the investigation form needs to be further evaluated.

Assessment of Sonographic Parameters for Predicting Primary Patency Rate in Hemodialysis Patients With Venous Valve-Related Stenosis

OBJECTIVES

Ultrasonography is more frequently used in patients with arteriovenous fistula (AVF) stenosis. The aim of this study is to use sonographic parameters for predicting primary patency in hemodialysis patients with venous valve-related stenosis (VVRS) who are treated by ultrasound-guided percutaneous transluminal angioplasty (PTA).

METHODS

A total of 229 VVRS patients who underwent PTA between January 2017 and December 2021 were enrolled. Clinical characteristics were retrospectively collected. Sonographic parameters were measured both before and after PTA. Univariate and multivariate Cox analyses were performed to identify independent factors associated with primary patency rate.

RESULTS

All measured sonographic parameters improved after PTA compared to before PTA. Before PTA, the diameter of VVRS > 1.0 mm, age ≤ 57 years, and body mass index (BMI) > 21.57 kg/m2 were associated with better outcomes. While the diameter of radial artery, proximal radial artery close to the anastomosis, brachial artery, the flow volume of brachial artery, the length and peak velocity (PV) of the VVRS, and the diameter and PV after the VVRS had no association with the primary patency rate. After PTA, only patients with a diameter of VVRS > 4.0 mm had favorable outcome. In addition, patients with a gain of diameter of VVRS > 2.4 mm after PTA had a trend of better outcomes.

CONCLUSIONS

The diameter of VVRS before and after PTA could be served as markers to predict primary patency rate and second patency rate in AVF patients with VVRS. The gain of diameter of VVRS could also be a potential marker.

CLINICAL IMPACT

Using simple markers of sonographic parameters, we could quickly identify patients with a higher risk of restenosis. These patients should be followed more closely in case of restenosis at early. It is also beneficial to the prevention of thrombosis. These measures help to preserve more valuable vascular for a long-term dialysis. Additionally, the physician should pay more attention on the dialysis-related complications in these risky patients, such as hemodialysis-related hypotension.

Beyond Conventional: A Systematic Review of Non-Conventional Techniques for Radio-Cephalic Arteriovenous Fistula

BACKGROUND

Radio-cephalic arteriovenous fistulas (RC-AVFs), the preferred vascular access for hemodialysis, have high failure rates. New techniques like the no-touch technique (NTT) and modified no-touch technique (MNTT) have shown promising results. Our objective is to highlight the effectiveness of nonconventional techniques, aiming to address the challenge of arteriovenous fistula (AVF) failure.

METHODS

We searched Medline, Google Scholar, and Clinicaltrials.gov until April 2023, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five relevant articles were found, all involving human studies on NTT or MNTT for RC-AVF creation. We focused on primary and secondary patency rates, fistula maturation rates, and complications.

RESULTS

We reviewed 5 studies as follows: 2 were pilot studies, 2 were prospective studies, and one was retrospective study. Three used NTT, and 2 used MNTT. Among double-arm studies, 3 out of 4 showed a significantly improved primary patency with nonconventional techniques. However, one study found no significant difference between nonconventional and conventional methods (90.5% vs. 84.2%; P = 0.225). In a single-arm study, nonconventional technique (NTT) displayed 54% primary patency at 1 year. Secondary patency rates were in 3 studies. One demonstrated significant secondary patency with nonconventional methods compared to conventional (90% vs. 67.5%; P = 0.028), while another found no significant difference (90.5% vs. 84.2%; P = 0.803). In the single-arm study, the nonconventional technique (NTT) revealed 80% secondary patency at 1 year.

CONCLUSIONS

Nonconventional techniques (NTT and MNTT) show promise in improving patency rates, hinting at their potential as alternatives to the conventional technique for RC-AVF creation. Further studies are crucial to confirm their effectiveness and evaluate long-term outcomes.

Late creation of vascular access increased post-hemodialysis mortality, hospitalization, and health-care expenditure: A population-based cohort study in Taiwan

BACKGROUND/PURPOSE

The optimal timing of vascular access (VA) creation for hemodialysis (HD) and whether this timing affects mortality and health-care utilization after HD initiation remain unclear. Thus, we conducted a population-based study to explore their association.

METHODS

We used Taiwan's National Health Insurance Research Database to analyze health-care outcomes and utilization in a cohort initiating HD during 2003-2013. We stratified patients by the following VA creation time points: >180, 91-180, 31-90, and ≤30 days before and ≤30 days after HD initiation and examined all-cause mortality, ambulatory care utilization/costs, hospital admission/costs, and total expenditure within 2 years after HD. Cox regression, Poisson regression, and general linear regression were used to analyze mortality, health-care utilization, and costs respectively.

RESULTS

We identified 77,205 patients who started HD during 2003-2013. Compared with the patients undergoing VA surgery >180 days before HD initiation, those undergoing VA surgery ≤30 days before HD initiation had the highest mortality-15.92 deaths per 100-person-years, crude hazard ratio (HR) 1.56, and adjusted HR 1.28, the highest hospital admissions rates- 2.72 admission per person-year, crude rate ratio (RR) 1.48 and adjusted RR 1.32, and thus the highest health-care costs- US$31,390 per person-year, 7% increase of costs and 6% increase with adjustment within the 2-year follow-up after HD initiation.

CONCLUSION

Late VA creation for HD can increase all-cause mortality, hospitalization, and health-care costs within 2 years after HD initiation. Early preparation of VA has the potential to reduce post-HD mortality and healthcare expenses for the ESKD patients.

Burden of CKD-Associated Pruritus and Adverse Clinical Outcomes in Patients Receiving Dialysis: The Stockholm CREAtinine Measurements (SCREAM) Project

RATIONALE & OBJECTIVE

Pruritus is a common but not well-characterized complaint of patients receiving maintenance dialysis. This study sought to quantify the burden of pruritus and its associated adverse health outcomes in this population.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

All patients receiving maintenance dialysis in Stockholm, Sweden, during 2005-2021.

EXPOSURE

Clinically recognized pruritus, defined using ICD-10 codes or the prescription for anti-pruritus treatments (including UV-therapy).

OUTCOMES

All-cause mortality, severe infection-related hospitalizations (composite of endocarditis, peritoneal dialysis-related peritonitis, hemodialysis/peritoneal dialysis-related catheter infection, sepsis due to Staphylococcus Spp., or skin infection) and incident diagnoses of anxiety/depression and sleep disorders.

ANALYTICAL APPROACH

Multivariable logistic regression and cause-specific hazards models to analyze factors associated with prevalent and new-onset pruritus, respectively. Multivariable cause-specific hazards models with time-varying exposure to explore the association of prevalent and new-onset pruritus with adverse health outcomes.

RESULTS

Among 3281 dialysis patients (median age 64 years, 66% men, 69% on hemodialysis,77% incident dialysis patients), 456 (14%) had pruritus at enrollment. During a median follow-up of 3.3 [IQR: 1.3-9.2] years, 539 (19%) additional patients developed pruritus. Older age, female sex, a lower serum albumin level, and higher C-reactive protein, serum calcium and phosphorus levels were independently associated with pruritus. Compared to patients without pruritus, patients with pruritus were at a higher risk of suffering sleep disorders (adjusted HR: 1.96 [95%CI 1.60-2.39]), developing anxiety/depression (aHR: 1.56 [1.23-1.98]), and being hospitalized for severe infections (aHR: 1.36 [1.18-1.57]), the latter attributed to higher risk of sepsis and peritoneal dialysis-related peritonitis. There was no detectable association between developing pruritus and all-cause mortality.

LIMITATIONS

Potential misclassification bias if pruritus is not clinically recognized; lack of information on pruritus intensity/severity; use of diagnostic codes for exposure and outcome diagnoses.

CONCLUSION

At least one-third of patients experience pruritus during their first years on dialysis, and pruritus was consistently associated with adverse health outcomes.

Type 2 diabetes increase the risk of arteriovenous fistula non-maturation, mediated by postoperative vascular hemodynamics

BACKGROUND

The progression of atherosclerosis in small and medium-sized vessels has been associated with Type 2 diabetes (T2D). However, the influence of T2D on postoperative vascular remodeling and arteriovenous fistula (AVF) maturation is inconclusive. Besides, hemodynamic changes of postoperative vessel are also associated with AVF maturation. This study is intended to investigate the link between T2D and the occurrence of AVF non-maturation, as well as to delve into the impact of postoperative vascular hemodynamic parameters in this process.

METHODS

A total of 477 hemodialysis patients, with or without type 2 diabetes, underwent AVF creation at Beijing Haidian Hospital (Haidian Section of Pecking University Third Hospital) from August 2018 to March 2022 were collected, and were followed for 1-5 years. Logistic regression was applied to analyze the association of T2D, postoperative vascular hemodynamic parameters with the risk of AVF non-maturation. To verify the stability of the results, the sensitivity analyses were performed using propensity scores to match patients. We further investigated the regulatory role of the postoperative vascular hemodynamics.

RESULTS

There were 173 patients with T2D and 304 patients without T2D in this study. The maturation rate in T2D and non-T2D group was 47.977% and 63.816%, respectively. The findings of logistic regression analysis suggested that T2D significantly increased the risk of AVF immaturity [OR 1.716 (1.019-2.890), P = 0.042]. Besides, T2D was associated with the restriction of postoperative vascular hemodynamic parameters changes, including with decreased diameter of forearm cephalic radial artery and dilation rate of radial artery. The result of logistic regression analysis indicated that cephalic vein diameter at 1-month [0.402 (0.237-0.681), P = 0.001] and cephalic vein diameter at 2-month [0.501 (0.355-0.708), P < 0.001] were independently correlated with AVF maturation. Besides, the results of sensitivity analysis were consistent with that of logistic regression analysis. Moreover, the mediating effects of cephalic vein diameter were significant.

CONCLUSION

Our findings discovered that T2D significantly increased the risk of arteriovenous fistula non-maturation, which was mainly mediated by the changes of cephalic vein diameter.

Tunneled central venous catheters for hemodialysis-unfairly condemned? Catheter-related complications in a university hospital setting

BACKGROUND

Central venous catheters (CVCs) provide an immediate hemodialysis access but are considered to be of elevated risk for complications. It remains unclear, if CVCs per se have relevant impact on clinical outcome. We provide an assessment of CVC-associated complications and their impact on mortality.

METHODS

In a single center retrospective study, CVC patients between JAN2015-JUN2021 were included. Data on duration of CVC use, complications and comorbidities was collected. Estimated 6-month mortality was compared to actual death rate.

RESULTS

About 478 CVCs were analyzed. Initiation of dialysis was the main reason for CVC implantation. Death was predominant for termination of CVC use. Infections were rare (0.6/1000 catheter days), complications were associated with certain comorbidities. Actual 6-month mortality was lower than predicted (14.3% vs 19.6%).

CONCLUSION

(1) CVCs are predominantly implanted for initiation of hemodialysis; (2) serious complications are rare; (3) complications are associated with certain comorbidities; and (4) CVC patients survive longer than predicted.

Management of infected arteriovenous grafts for haemodialysis: Outcomes and strategies using a novel objective scoring system

BACKGROUND

In haemodialysis patients with exhausted autogenous options, prosthetic arteriovenous grafts (AVGs) are frequently utilised as tertiary vascular access. However, the prosthetic nature of AVGs precipitates an increased risk of infection which may translate to excess morbidity and life-threatening complications. The current evidence remains divided on the optimal treatment strategy for arteriovenous graft infections (AVGi) with arguments for conservative management by antibiotics, salvaging with graft revision or total/subtotal excision. To address this gap, we assessed the outcomes of AVGi patients treated in our institution, developing an AVGi severity classification model and a proposed treatment algorithm to guide AVGi management.

METHODS

We conducted a single centre retrospective review of outcomes of patients with AVGi managed either by sole antibiotics therapy, graft revision or surgical excision between June 2016 and May 2021. Outcomes of AVGi patients across differing treatment groups were compared, including 1-year mortality, 6-month and 1-year functional vascular access. We also analysed the outcomes of tunnelled haemodialysis lines (THL), which were used as a temporary vascular access in several AVGi patients in our study.

RESULTS

A total of 34 AVGi patients were managed within that time frame and included in the study (5 conservatively management by antibiotics, 5 graft revisions and 24 surgical excision) with a mean age of 60.4 ± 14.4 years (67.6% males). Overall 1-year mortality was 14.7%. A 6-month functional vascular access status across the three groups stood at 60%, 60% and 10% while 1-year functional vascular access status was 60%, 75% and 42% respectively.

CONCLUSIONS

When clinically appropriate, conservative management by antibiotics or salvage/graft revision can present as prudent AVGi treatment options. The adoption of our proposed severity classification system and treatment algorithm provides a more thorough objective assessment of the infection and helps guide the clinical decision-making process.

Surgical planning of arteriovenous fistulae in routine clinical practice: A machine learning predictive tool

BACKGROUND

Arteriovenous fistula (AVF) is the preferred vascular access (VA) for hemodialysis, but it is associated with high non-maturation and failure rates. Predicting patient-specific AVF maturation and postoperative changes in blood flow volumes (BFVs) and vessel diameters is of fundamental importance to support the choice of optimal AVF location and improve VA survival. The goal of this study was to employ machine learning (ML) in order to give physicians a fast and easy-to-use tool that provides accurate patient-specific predictions, useful to make AVF surgical planning decisions.

METHODS

We applied a set of ML approaches on a dataset of 156 patients. Both parametric and non-parametric ML approaches, taking preoperative data as input, were exploited to predict maturation, postoperative BFVs, and diameters. The best approach associated with lowest cross-validation errors between predictions and real measurements was then chosen to provide estimates and quantify prediction errors.

RESULTS

The k-NN was the best approach to predict brachial BFV, AVF maturation, and other VA variables, and it was also associated with the least computational effort. With this approach, the confusion matrices proved the high accuracy of the prediction for AVF maturation (96.8%) and the low absolute error distribution for the continuous BFV and diameter variables.

CONCLUSIONS

Our data-based approach provided accurate patient-specific predictions for different AVF configurations, requiring short computational time as compared to a physical model we previously developed. By supporting VA surgical planning, this fast computing approach could allow AVF surgical planning and help reducing the rate of non-maturation, which might ultimately have a broad impact on the management of hemodialysis patients.

Comparison between the 0- and 30-s balloon dilation time in percutaneous transluminal angioplasty for restenosed arteriovenous fistula among hemodialysis patients: a multicenter, prospective, randomized trial (CARP study)

BACKGROUND

This study aims to compare patency rates of the 0- and 30-s (sec) balloon dilation time in hemodialysis (HD) patients with restenosis after percutaneous transluminal angioplasty (PTA).

METHODS

The patients who underwent PTA within 6 months for failed arteriovenous fistula at the forearm were randomly assigned the 0-s or 30-s dilation time group. Effect of dilation time on the 3- and 6-month patency rates after PTA was examined.

RESULTS

Fifty patients were enrolled in this study. The 3-month patency rate in the 30-s dilation group was better than that in the 0-s dilation group (P = 0.0050), while the 6-month patency rates did not show a significant difference between the two groups (P = 0.28). Cox's proportional hazard model revealed that 30-s of inflation time (hazard ratio 0.027; P = 0.0072), diameter of the proximal (hazard ratio 0.32; P = 0.031), and dilation pressure (hazard ratio 0.63; P = 0.014) were associated with better 3-month patency. Dilation pressure between previous and present PTA did not differ in the 0-s (P = 0.15) and 30-s dilation groups (P = 0.16). The 6-month patency rate of the present PTA in the 30-s dilation group was higher than that of the previous PTA (P = 0.015). The visual analog scale did not differ between the two groups (P = 0.51).

CONCLUSION

The presenting data suggest that 30-s dilation potentially results in a better 3-month patency rate than 0-s dilation in HD patients with restenosis after PTA.

Intraoperative transit time flow measurement predicts maturation of radiocephalic arteriovenous fistulas

OBJECTIVE

The arteriovenous fistula (AVF) is the first choice for gaining vascular access for hemodialysis. However, 20% to 50% of AVFs fail within 4 months after creation. Although demographic risk factors have been described, there is little evidence on the intraoperative predictors of AVF maturation failure. The aim of this study was to assess the predictive value of intraoperative transit time flow measurements (TTFMs) on AVF maturation failure.

METHODS

In this retrospective cohort study, intraoperative blood flow, measured using TTFM, was compared with AVF maturation after 6 weeks in 55 patients. Owing to its significantly higher prevalence and risk of nonmaturation, the radiocephalic AVF (RCAVF) was the main focus of this study. A recommended cutoff point for high vs low intraoperative blood flow was determined for RCAVFs, using a receiver operating characteristic curve.

RESULTS

The average intraoperative blood flow in RCAVFs was 156 mL/min. Patients with an intraoperative blood flow equal or lower than the determined cutoff point of 160 mL/min, showed a 3.03 times increased risk of AVF maturation failure after 6 weeks, compared with patients with a higher intraoperative blood flow (P < .001).

CONCLUSIONS

The intraoperative blood flow in RCAVFs measured by TTFM provides an adequate means of predicting AVF nonmaturation 6 weeks after surgery. For RCAVFs, a cutoff point for intraoperative blood flow of 160 mL/min is recommended for maximum sensitivity and specificity to predict AVF maturation failure after 6 weeks.

Replacement Strategies for Tunneled Hemodialysis Catheters with Complications: A Nationwide Cohort Study

Key Points

Background

Tunneled hemodialysis catheters often have infectious or mechanical complications that require unplanned removal and replacement, but the optimal replacement strategy is unknown. This study described the real-world use of two strategies in Australia and compared the survival of replacement catheters inserted by either strategy.

Methods

Observational data from the REDUcing the burden of dialysis Catheter ComplicaTIOns: a National approach trial, which enrolled a nationwide cohort of 6400 adults who received an incident hemodialysis catheter (2016–2020), was used for this secondary analysis. Tunneled catheters were replaced by either catheter exchange through the existing tunnel tract or removal and replacement through a new tract. The effect of the replacement strategy on the time to catheter removal because of infection or dysfunction was estimated by emulating a hypothetical pragmatic randomized trial among a subset of 434 patients with mechanical tunneled catheter failure.

Results

Of 9974 tunneled hemodialysis catheters inserted during the trial, 380 had infectious and 945 had mechanical complications that required replacement. Almost all infected hemodialysis catheters (97%) were removed and separately replaced through a new tunnel tract, whereas nephrology services differed widely in their replacement practices for catheters with mechanical failure (median=50% guidewire exchanged, interquartile range=30%–67%). Service-level differences accounted for 29% of the residual variation after adjusting for patient factors. In the target trial emulation cohort of patients with mechanical catheter failure (n=434 patients), catheter exchange was not associated with lower complication-free survival at 1, 6, or 12 months (counterfactual survival difference at 1 month=5.9%; 95% confidence interval, −2% to 14%).

Conclusions

Guidewire exchange for mechanical failure of catheter was not associated with lower catheter survival and may be preferable for patients.

Trial registration and protocol:

The trial was registered in the Australia and New Zealand clinical trials registry on the June 23, 2016 (ACTRN12616000830493).

A Modified Switching Procedure from Temporary to Tunneled Central Venous Dialysis Catheters

Background: Tunneled central venous catheters are commonly used for dialysis in patients without a functional permanent vascular access. In an emergent setting, a non-tunneled, temporary central venous catheter is often placed for immediate dialysis. The most critical step in the catheter insertion is venipuncture, which is often a major cause for longer intervention times and procedure-related adverse events. To avoid this critical step when placing a more permanent tunneled catheter, an exchange over a previously placed temporary one can be considered. In this paper, we present a modified switching approach with a separate access site. Methods: In this retrospective analysis of a prospective database, we examined whether this modified technique is non-inferior to a de novo application. Therefore, we included all 396 patients who received their first tunneled dialysis catheter at our site from March 2018 to March 2023. Out of these, 143 patients received the modified approach and 253 the standard de novo ultrasound-guided puncture and insertion. Then, the outcomes of the two groups, including adverse events and infections, were compared by nonparametric tests and multivariable logistic regression. Results: In both groups, the implantations were 100% successful. Catheter explantation due to infection according to CDC criteria was necessary in 18 cases, with no difference between the groups (5.0% vs. 4.4% p = 0.80). The infection rate per 100 days was 0.113 vs. 0.106 in the control group, with a comparable spectrum of bacteria. A total of 12 catheters (3 vs. 9) had to be removed due to a periinterventional complication. An early-onset infection was the reason in two cases (1.3%) in the study group and five in the control group (1.9%). A total misplacement of the catheter occurred in two cases only in the control group. After adjustment for potential confounders via multivariable logistic regression there was not a significant difference in the complication rate (adjusted odds ratio, aOR = 0.53, 95% CI = 0.14-2.03, p = 0.351) but an estimated decreased risk overall based on the average treatment effect of -1.7% in favor of the study group. Conclusions: The present study shows that a catheter exchange leads to no more infections than a de novo placement; hence, it is a feasible method. Moreover, misplacements and control chest X-rays to exclude pneumothorax after venipuncture were completely avoided by exchanging. This approach yields a much lower infection rate than previous reports: 1.3% compared to 2.7% in all existing aggregated studies. The presented approach seems to be superior to existing switching methods. Overall, an exchange can also help to preserve veins for future access, since the same jugular vein is used.

Patients, healthcare providers, and general population preferences for hemodialysis vascular access: a discrete choice experiment

Background

A patient-centered dialysis treatment option requires an understanding of patient preferences for alternative vascular accesses and nephrologists often face difficulties when recommending vascular access to end-stage kidney disease (ESKD) patients. We aimed to quantify the relative importance of various vascular access characteristics to patients, healthcare providers and general population, and how they affect acceptability for patients and healthcare providers.

Methods

In a discrete choice experiment, patients with maintenance hemodialysis (MHD), healthcare providers, and individuals from the general population were invited to respond to a series of hypothetical vascular access scenarios that differed in five attributes: cumulative patency, infection rate, thrombosis rate, cost, and time to maturation. We estimated the respondents' preference heterogeneity and relative importance of the attributes with a mixed logit model (MXL) and predicted the willingness to pay (WTP) of respondents via a multinomial logit model (MNL).

Results

Healthcare providers (n = 316) and the general population (n = 268) exhibited a favorable inclination toward longer cumulative patency, lower access infection rate and lower access thrombosis rate. In contrast, the patients (n = 253) showed a preference for a 3-year cumulative patency, 8% access infection rate, 35% access thrombosis rate and 1.5 access maturity time, with only the 3-year cumulative patency reaching statistical significance. Among the three respondent groups, the general population found cumulative patency less important than healthcare providers and patients did. Patients demonstrated the highest WTP for cumulative patency, indicating a willingness to pay an extra RMB$24,720(US$3,708) for each additional year of patency time.

Conclusion

Patients and healthcare providers had a strong preference for vascular access with superior patency. While the general population preferred vascular access with lower thrombosis rates. These results indicate that most patients prefer autogenous arteriovenous fistula (AVF) as an appropriate choice for vascular access due to its superior patency and lower complications than other vascular access types.

Global variations in funding and use of hemodialysis accesses: an international report using the ISN Global Kidney Health Atlas

BACKGROUND

There is a lack of contemporary data describing global variations in vascular access for hemodialysis (HD). We used the third iteration of the International Society of Nephrology Global Kidney Health Atlas (ISN-GKHA) to highlight differences in funding and availability of hemodialysis accesses used for initiating HD across world regions.

METHODS

Survey questions were directed at understanding the funding modules for obtaining vascular access and types of accesses used to initiate dialysis. An electronic survey was sent to national and regional key stakeholders affiliated with the ISN between June and September 2022. Countries that participated in the survey were categorized based on World Bank Income Classification (low-, lower-middle, upper-middle, and high-income) and by their regional affiliation with the ISN.

RESULTS

Data on types of vascular access were available from 160 countries. Respondents from 35 countries (22% of surveyed countries) reported that > 50% of patients started HD with an arteriovenous fistula or graft (AVF or AVG). These rates were higher in Western Europe (n = 14; 64%), North & East Asia (n = 4; 67%), and among high-income countries (n = 24; 38%). The rates of > 50% of patients starting HD with a tunneled dialysis catheter were highest in North America & Caribbean region (n = 7; 58%) and lowest in South Asia and Newly Independent States and Russia (n = 0 in both regions). Respondents from 50% (n = 9) of low-income countries reported that > 75% of patients started HD using a temporary catheter, with the highest rates in Africa (n = 30; 75%) and Latin America (n = 14; 67%). Funding for the creation of vascular access was often through public funding and free at the point of delivery in high-income countries (n = 42; 67% for AVF/AVG, n = 44; 70% for central venous catheters). In low-income countries, private and out of pocket funding was reported as being more common (n = 8; 40% for AVF/AVG, n = 5; 25% for central venous catheters).

CONCLUSIONS

High income countries exhibit variation in the use of AVF/AVG and tunneled catheters. In low-income countries, there is a higher use of temporary dialysis catheters and private funding models for access creation.

Cost-effectiveness analysis of autogenous arteriovenous fistula, arteriovenous graft, and tunneled-cuffed catheter for hemodialysis in patients with end-stage kidney disease in Southern China

OBJECTIVES

To evaluate the cost-effectiveness of three permanent vascular accesses for maintenance hemodialysis patients from a hospital perspective throughout 5 years, which is the average life expectancy of patients with end-stage kidney disease.

SUBJECTS AND METHODS

We conducted a EuroQol(EQ-5D) questionnaire survey between January 2021 and March 2021 with 250 patients to estimate the health utility of various states in patients under different hemodialysis vascular access. We designed a Markov model and conducted a cost-effectiveness analysis to compare the cost-effectiveness of three hemodialysis vascular access in Guangzhou throughout 5 years.

RESULTS

The mean costs were US$44,481 with tunneled-cuffed catheter (TCC), and US$68,952 and US$59,247 with arteriovenous graft (AVG) and autogenous arteriovenous fistula (AVF), respectively. The mean quality-adjusted life-years (QALYs) was 1.41 with TCC, and 2.37 and 2.73 with AVG and AVF, respectively. AVG had an incremental cost-effectiveness ratio (ICER) of US$25,491 per QALY over TCC; AVF had an ICER of -US$26,958 per QALY over AVG. At a willingness to pay below US$10,633.8 per QALY, TCC is likely the most cost-effective vascular access. At any willingness to pay between US$10,633.8 and US$30,901.4 per QALY, AVF is likely the most cost-effective vascular access.

CONCLUSION

These findings illustrate the value of AVF given its relative cost-effectiveness to other hemodialysis modalities. Although AVG costs much more than TCC for slightly higher QALYs than TCC, AVG still has a greater advantage over TCC for patients with longer life expectancy due to its lower probability of death.

Primary and specialist care interaction and referral patterns for individuals with chronic kidney disease: a narrative review

BACKGROUND

Timely referral of individuals with chronic kidney disease from primary care to secondary care is evidenced to improve patient outcomes, especially for those whose disease progresses to kidney failure requiring kidney replacement therapy. A shortage of specialist nephrology services plus no consistent criteria for referral and reporting leads to referral pattern variability in the management of individuals with chronic kidney disease.

OBJECTIVE

The objective of this review was to explore the referral patterns of individuals with chronic kidney disease from primary care to specialist nephrology services. It focused on the primary-specialist care interface, optimal timing of referral to nephrology services, adequacy of preparation for kidney replacement therapy, and the role of clinical criteria vs. risk-based prediction tools in guiding the referral process.

METHODS

A narrative review was utilised to summarise the literature, with the intent of providing a broad-based understanding of the referral patterns for patients with chronic kidney disease in order to guide clinical practice decisions. The review identified original English language qualitative, quantitative, or mixed methods publications as well as systematic reviews and meta-analyses available in PubMed and Google Scholar from their inception to 24 March 2023.

RESULTS

Thirteen papers met the criteria for detailed review. We grouped the findings into three main themes: (1) Outcomes of the timing of referral to nephrology services, (2) Adequacy of preparation for kidney replacement therapy, and (3) Comparison of clinical criteria vs. risk-based prediction tools. The review demonstrated that regardless of the time frame used to define early vs. late referral in relation to the start of kidney replacement therapy, better outcomes are evidenced in patients referred early.

CONCLUSIONS

This review informs the patterns and timing of referral for pre-dialysis specialist care to mitigate adverse outcomes for individuals with chronic kidney disease requiring dialysis. Enhancing current risk prediction equations will enable primary care clinicians to accurately predict the risk of clinically important outcomes and provide much-needed guidance on the timing of referral between primary care and specialist nephrology services.

Survival, cumulative hospital days and infectious complications in urgent-start PD compared with urgent-start HD

BACKGROUND

Urgent-start peritoneal dialysis (PD) carries a similar efficacy and safety profile compared to urgent-start haemodialysis (HD) but is only sparsely applied due to resource issues and concerns of complication risks. Furthermore, few data exist on adverse outcomes associated with central venous catheter (CVC) insertions in urgent-start HD patients. Thus, we sought to compare patient and dialysis-related outcomes in patients undergoing urgent-start PD or HD.

METHODS

All patients initiating urgent-start PD in a tertiary research hospital in 2005-2018 were included in this retrospective, single-centre, comparative study and matched with urgent-start HD patients of similar age and chronic kidney disease aetiology. All urgent-start PDs were initiated within 72 h after catheter insertion, and urgent-start HDs were performed via a CVC. All analyses were performed at 3 months and at 1 year of follow-up, respectively.

RESULTS

Thirty-three patients who commenced urgent-start PD and 58 matched urgent-start HD control patients were included. Altogether, 26 patients (29%; PD: 36%, HD 24%) died within the 1-year follow-up, and patient survival was similar at 3 months (hazard ratio (HR): 1.15, 95% confidence interval (CI): 0.35-3.81, p = 0.82) and at 1 year of follow-up (HR: 0.64, 95% CI: 0.30-1.39, p = 0.26) between the study groups. There were no differences in the total kidney replacement therapy (KRT)-related infection rate (p = 0.66) or cumulative first-year hospital care days (p = 0.43) between the treatment groups. Altogether, 139 CVCs were inserted during the 1-year follow-up. The number of CVCs per patient was associated with the emergence of blood culture-positive bacteraemia and increased cumulative first-year hospital care days.

CONCLUSIONS

Patient survival, cumulative first-year hospital care days and total KRT-related infection rate at 3 months and 1-year follow-up are similar between urgent-start PD and urgent-start HD patients. Furthermore, CVC insertion rate is associated with incident blood culture-positive bacteraemia and increased cumulative first-year hospital care days.

Minimizing delays to hemodialysis access maturation: A quality improvement analysis

INTRODUCTION

Pre-operative process optimization can expedite time-to-intervention and reduce overall health care costs. We hypothesized that the longest delay to hemodialysis (HD) access creation would be from pre-operative vessel mapping (mandatory in our practice), and that this would be correlated with increased catheter days.

METHODS

One hundred thirty patients (24 inpatients, 106 outpatients) who received initial hemodialysis (HD) access from 01/01/2017 to 12/31/2021, at the Veterans Affairs Puget Sound, Seattle, Washington, were identified. Median time differences between pre-operative events were compared between inpatients and outpatients using the Mann-Whitney U test. Outpatients were then stratified by time of catheter-based HD initiation (no catheter, pre-referral catheter, post-referral catheter) and compared. The impacts of mapping-related delays on catheter use were evaluated using regression.

RESULTS

Inpatients had shorter referral to access maturation times (125 days inpatient vs 146 days outpatient; p = 0.03). This was driven by shorter referral to mapping (2 days inpatient vs 27 days outpatient; p < 0.01) and mapping to pre-surgical evaluation (1-day inpatient vs 6 days outpatients; p < 0.01) times. Pre-surgical evaluation to OR times represented the longest pre-operative delay in both groups (51 days inpatient vs 29 days outpatient; p = 0.59). Among outpatients, tunneled catheter placement post-referral resulted in longer maturation times (74 days no catheter vs 67 days pre-referral vs 149 days post-referral; p < 0.01) but not additional pre-operative delays. No trend existed between increased mapping times and catheter-based dialysis duration (R2 = 0.08).

CONCLUSION

Preoperative vein mapping contributed up to 21% of referral to maturation times but was not associated with increased tunneled catheter duration. While tunneled catheter placement impacted access maturation it did not cause additional pre-operative delays. Earlier referrals for access creation and reduction of outpatient wait-time from referral to OR and increased AV graft placement may minimize catheter days in our system thereby mitigating the added delays caused by pre-operative vein mapping.

Accuracy of 3.0T magnetic resonance angiography for the detection of arteriovenous fistula dysfunction in hemodialysis patients requiring interventional therapy: a prospective study

Background

Color Doppler ultrasonography (CDUS) is feasible to detect arteriovenous fistula (AVF) dysfunction in hemodialysis patients but is not sufficient to map the structure of fistula required for interventions. This study is designed to evaluate the diagnostic accuracy of three-dimensional time-of-flight magnetic resonance angiography (TOF-MRA) at 3.0T versus CDUS for AVF dysfunction, by using digital subtraction angiography (DSA) as reference.

Methods

This prospective study enrolled 68 consecutive patients with dysfunctional AVF who underwent both CDUS and TOF-MRA at Shanghai Sixth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine. The analysis of the dysfunctional AVFs was divided into three regions: the feeding artery, fistula and draining veins. In the whole- and per-regional-based analyses, two observers who were blinded to the clinical and DSA results independently analyzed all CDUS and TOF-MRA datasets. The image quality and stenosis severity of the lesions on TOF-MRA were evaluated. A receiver operating characteristic curve was applied to analyze the detection of AVF dysfunction with TOF-MRA.

Results

A total of 204 vessel regions were evaluated. The whole-region-based image quality of TOF-MRA was poorer in patients with a total occlusion (1.8±0.8) than in those with stenosis (2.7±0.6, P<0.001). In the whole-region analyses, TOF-MRA had higher sensitivity [99.1% (94.6-100.0%) vs. 82.9% (74.6-89.0%), P<0.001] and similar specificity [93.1% (85.0-97.1%) vs. 94.3% (86.5-97.9%), P=0.755] than CDUS. The per-region-based analyses showed that TOF-MRA yielded higher sensitivity [fistula region, 98.1% (88.4-99.9%) vs. 80.8% (67.0-89.9%); P=0.004; draining vein region, 100.0% (92.5-100.0%) vs. 85.0% (72.9-2.5%); P=0.003] and similar specificity [fistula region, 88.2% (62.3-97.8%) vs. 88.2% (62.3-97.9%); P>0.99; draining vein region, 100.0% (59.8-100.0%) vs. 87.5% (46.7-99.3%); P>0.99] than CDUS. Sensitivity and specificity of TOF-MRA were comparable to those of CDUS in feeding artery region.

Conclusions

TOF-MRA is a feasible and accurate method to display AVF dysfunction in hemodialysis patients, and this method might fulfill the endovascular treatment planning requirements.

Vascular access route venture of the chronic hemodialysis patient: A prospective cohort study

OBJECTIVES

This study aimed to collect evidence to improve the arteriovenous fistula practice by investigating vascular access routes and by identifying the factors influencing the preferred types of vascular access routes for the first-time hemodialysis in our center.

METHODS

We performed an epidemiological, prospective, cohort study. The study included 308 patients, who underwent hemodialysis for the first time between March 2023 and August 2023 in our hemodialysis center. We evaluated biochemical parameters, preferred vascular access routes for the first-time hemodialysis, planned/emergency hemodialysis status, the qualifications of the healthcare provider, who inserted the central venous catheter, if applicable, the presence of hypervolemia, anticoagulant use, nephrology follow-up findings, and in-hospital mortality in all patients and in those, who continued with chronic hemodialysis.

RESULTS

The number of patients, who continued with chronic hemodialysis, was 167 (54.2%) and a temporary internal jugular central venous catheter was the most commonly preferred vascular access route for the first-time hemodialysis (47.3%). A central venous catheter was most commonly inserted by a nephrologist (53.7%) in chronic hemodialysis patients. Of the patients continuing with chronic hemodialysis, 45.5% were followed up in the nephrology outpatient clinic, 9.6% initiated hemodialysis on a planned basis, and 8.4% initiated hemodialysis with an arteriovenous fistula. A temporary internal jugular central venous catheter was commonly preferred when patients were followed up in the nephrology clinic and when the insertion was performed by a nephrologist; a transient femoral central venous catheter was commonly preferred in case of hypervolemia (p < .001, p < .001, and p = .028, respectively). Age, gender, etiology, anticoagulant use, or biochemical test results did not act on the selection of the access site for the insertion of central venous catheter at the time of the first hemodialysis treatment. The access site for central venous catheter was not associated with in-hospital mortality (p = .644). In the overall patient group, the in-hospital mortality was significantly low in patients followed up in the nephrology clinic (p = .014).

CONCLUSION

The use of pre-emptive arteriovenous fistula for the first hemodialysis treatment occurs much less commonly than expected. Hemodialysis initiation rates with pre-emptive arteriovenous fistula lag behind nephrology outpatient follow-up rates.

Comparison between transposed arteriovenous fistulas and arteriovenous graft for the hemodialysis patients: A meta-analysis and systematic review

It is challenging for a surgeon to determine the appropriate vascular access for hemodialysis patients whose cephalic vein is usually inaccessible. The purpose of the study is to compare the complications and patency rates between transposed arteriovenous fistulas (tAVF) and arteriovenous graft (AVG) for the hemodialysis patients. Studies were recruited from PubMed, Cochrane library, EMBASE, the web of science databases, and reviewing reference lists of related studies from the inception dates to September 2, 2021. Statistical analyses were conducted using the statistical tool Review Manager version5.3 (Cochrane Collaboration, London, UK). I2 > 50% was defined as a high degree of heterogeneity, and then a random-effects model was used. Otherwise, the fixed-effects model was used. Odds ratio with its 95% confidence interval (95% CI) was used. Thirty-three trials (26 retrospective studies, four randomized controlled trials, two prospective trials, and one controlled-comparative study) with 6430 enrolled participants were identified in our analysis. The results showed that tAVF was accompanied with lower thrombosis rate (103/1184 (8.69%) vs 257/1367 (18.80%); I2 = 45%; 95% CI, 0.34 (0.26, 0.45)) and infection rate (43/2031 (2.12%) vs 180/2147 (8.38%); I2 = 0%; 95% CI, 0.20 (0.14, 0.30)) than arteriovenous graft. The significantly better primary patency rates, secondary patency rates, and primary assisted patency rates during follow-up were found in tAVF. However, the failure rate and the prevalence of hematoma were significantly lower in AVG group. No evidence showed the rate of overall mortality, steal syndrome, and aneurysm reduced in tAVF. Our results showed that tAVF is a promising vascular access technique for hemodialysis patients whose cephalic vein is inaccessible. Our data showed that tAVF has less thrombosis, infection risk, and better patency rates when compared with AVG. However, more attentions need to be paid to transposed arteriovenous fistulas maturation and hematoma.

Comparative effectiveness and safety among different tip-design hemodialysis long-term catheters: A meta-analysis

PURPOSE

The aim of this meta-analysis is to compare effectiveness and safety among different tip-design long-term hemodialysis (HD) catheters.

MATERIALS AND METHODS

PubMed, Embase, and Cochrane Library databases were searched until 8 December 2021 to identify randomized controlled trials (RCTs) and cohort studies comparing step-tip, split-tip, or symmetrical-tip design catheters in patients undergoing HD will be included. The Cochrane Risk of Bias tool and the Newcastle-Ottawa Scale were used to evaluate the quality of RCTs and cohort studies. Data extracted from the articles were integrated to determine mean effective blood pump velocity (Qb), blood recirculation rates, secondary patency, catheter-related infection, catheter-related blood stream infection (CRBSI), thrombosis rates, and all-cause mortality for the three tip-designs. We performed meta-analysis on dichotomous outcomes using a random-effects model to evaluate risk ratios (RRs) and 95% confidence intervals (Cls). The effect sizes of continuous outcomes were reported as the mean difference (MD). Sensitivity and subgroup analyses were also performed. The study was registered in the PROSPERO (CRD42021297069).

RESULTS

Six RCTs and 11 cohort studies of 2617 individuals were included in our meta-analysis, of which 1088 individuals inserted split-tip catheters, 897 individuals inserted step-tip catheters and 650 received symmetrical-tip design catheters. Sym-tip performed better in mean Qb (MD = 43.85, 95% Cl = 18.13-69.56, p = 0.0008) than step-tip. Split-tip had better outcomes vs step-tip in blood recirculation (RR = 3.44, 95% Cl = 2.49-4.39, p < 0.00001). Sym-tip had significantly better outcomes compared with step-tip (RR = 0.28, 95%Cl = 0.09-0.81, Z = 2.34, p = 0.02) and split-tip (RR = 0.19, 95% Cl = 0.09-0.43, p < 0.0001) in thrombotic events. No significant difference was found in secondary patency, infection rates, CRBSI, and all-cause mortality among the three tip-designs.

CONCLUSION

The sym-tip of tunneled cuffed catheters performed better mean Qb, lower thrombotic events, and lower blood recirculation when blood line reversed, which may have an advantage over other two catheter-tips.

Stent migration as complication of endovascular treatment of vascular access stenosis: A systemic review

Outflow vein stenosis is one of the commonest complications of both native and prosthetic vascular access. Together with angioplasty, first-line treatment is stenting. Although it has been described as a uncommon complication, the risk of stent migration should be always considered. We aimed to conduct a systematic review of literature concerning stents migration in vascular access, the possible outcomes and treatments. This study was performed applying Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches were conducted in PubMed/Medline, Scopus, and Google scholar databases. Studies selection, data abstraction was done by two different reviewers. We identified 17 studies, comprising 18 cases (M:F 1:1, mean age 56 ± 18 (range 33-88)). All the patients underwent stenting for vascular access outflow stenosis. The commonest type of device reported was self expandible bare-metal stent. Intraoperative evidence of stent migration occurred in six cases at the final quality control, or for intraprocedure dyspnea onset. In two patients it was a incidental diagnosis. In the remaining cases, chest pain or dyspnea were the common delayed presentation symptoms. Even if stent migration is an uncommon event, it is burdened with low mortality and morbidity. Literature provide only few and frequently inadequate data. Stent removal is the treatment of choice when severe symptoms or cardiopulmonary complication are present. Endovascular procedures demonstrated to be an effective and safe alternative, while open surgical treatment is preferred whenever endovascular therapy failed or in selected cases.

The Assessment of Infection Risk in Patients with Vitiligo Undergoing Dialysis for End-Stage Renal Disease: A Retrospective Cohort Study

Vitiligo is an autoimmune condition that causes patchy skin depigmentation. Although the mechanism by which vitiligo induces immunocompromise is unclear, other related autoimmune diseases are known to predispose those affected to infection. Individuals with vitiligo exhibit epidermal barrier disruption, which could potentially increase their susceptibility to systemic infections; patients with renal disease also show a predisposition to infection. Nevertheless, there is little research addressing the risk of infection in dialysis patients with vitiligo in comparison to those without it. A retrospective analysis was performed on patients with end-stage renal disease (ESRD) in the United States Renal Data System who started dialysis between 2004 and 2019 to determine if ESRD patients with vitiligo are at an increased risk of bacteremia, cellulitis, conjunctivitis, herpes zoster, or septicemia. Multivariable logistic regression modeling indicated that female sex, black compared to white race, Hispanic ethnicity, hepatitis C infection, and tobacco use were associated with an enhanced risk of vitiligo, whereas increasing age and catheter, versus arteriovenous fistula, and access type were associated with a decreased risk. After controlling for demographics and clinical covariates, vitiligo was found to be significantly associated with an increased risk of bacteremia, cellulitis, and herpes zoster but not with conjunctivitis and septicemia.

Efficacy and safety of Apixaban for the prevention of thrombosis in arteriovenous grafts

This research aims to fill a vital gap in existing studies by evaluating the efficacy and safety of Apixaban, a direct oral anticoagulant, in the prevention of arteriovenous graft (AVG) thrombosis, thereby offering substantial insights into alternative anticoagulant options for hemodialysis patients. Conducted as a multi-center, randomized, double-blind, placebo-controlled trial, this study involved end-stage renal disease (ESRD) patients who had recently received polytetrafluoroethylene grafts. Participants were assigned to receive either Apixaban at a dose of 2.5 mg twice daily or a placebo. The primary outcome measure was the occurrence of graft thrombosis, while secondary outcomes focused on the incidence and severity of bleeding. Analytical methods included Kaplan-Meier estimates, Cox proportional hazards models, and conventional statistical tests. With 96 patients enrolled, the study found that Apixaban significantly reduced the incidence of AVG thrombosis compared to placebo (16.7% vs. 62.5%, P < 0.0001). Notably, this reduction in thrombosis incidence was not accompanied by an increase in bleeding events, thus affirming the safety profile of Apixaban as established in prior research. Apixaban is identified as an efficacious alternative to traditional anticoagulants in the prevention of AVG thrombosis among hemodialysis patients, representing a notable advancement in the care of individuals with ESRD. The results of this study support further investigations into the optimal dosing strategies specifically tailored for this patient demographic.

Bioinformatics identifies predictors of arteriovenous fistula maturation

BACKGROUND

Arteriovenous fistulae (AVF) are the preferred access for hemodialysis but still have poor rates of maturation and patency limiting their clinical use. The underlying mechanisms of venous remodeling remain poorly understood, and only limited numbers of unbiased approaches have been reported.

METHODS

Biological Gene Ontology (GO) term enrichment analysis and differentially expressed genes (DEG) analysis were performed for three AVF datasets. A microRNA enrichment analysis and L1000CDS2 query were performed to identify factors predicting AVF patency.

RESULTS

The inflammatory and immune responses were activated during both early and late phases of AVF maturation, with upregulation of neutrophil and leukocyte regulation, cytokine production, and cytokine-mediated signaling. In men with failed AVF, negative regulation of myeloid-leukocyte differentiation and regulation of macrophage activation were significantly upregulated. Compared to non-diabetic patients, diabetic patients had significantly reduced immune response-related enrichment such as cell activation in immune response, regulation of immune-effector process, and positive regulation of defense response; in addition, diabetic patients showed no enrichment of the immune response-regulating signaling pathway.

CONCLUSIONS

These data show coordinated, and differential regulation of genes associated with AVF maturation, and different patterns of several pathways are associated with sex differences in AVF failure. Inflammatory and immune responses are activated during AVF maturation and diabetes may impair AVF maturation by altering these responses. These findings suggest several novel molecular targets to improve sex specific AVF maturation.

The clinical journey and healthcare resources required for dialysis access of end-stage kidney disease patients during their first year of hemodialysis

BACKGROUND

Creation and maintenance of dialysis vascular access (VA) is a major component of healthcare resource utilization and cost for patients newly started on hemodialysis (HD). Different VA format arises due to patient acceptance of anticipatory care versus late preparation, and clinical characteristics. This study reviews the clinical journey and resource utilization required for different VA formats in the first year of HD.

METHOD

Data of patients newly commenced on HD between July 2015 and June 2016 were reviewed. Patients were grouped by their VA format: (A) pre-emptive surgically created VA (SCVA), (B) tunneled central venous catheter (CVC) followed by SCVA creation, (C) long-term tunneled CVC only. Clinical events, number of investigations and procedures, hospital admissions, and incurred costs of the three groups were compared.

RESULTS

In the multivariable analysis, the cost incurred by the group A patients had no significant difference to that incurred in the group B patients (p = 0.08), while the cost of group C is significantly lower (p < 0.001). Both the 62.7% of group A with successful SCVA who avoided tunneled CVC usage, and those with a functionally matured SCVA in group B (66.1%), used fewer healthcare resources and incurred less cost for their access compared to those did not (p = 0.01, p = 0.02, respectively) during the first year of HD.

CONCLUSION

With comparable cost, a pre-emptive approach enables avoidance of tunneled CVC. Tunneled CVC only access format incurred lower cost and is suitable for carefully selected patients. Successful maturation of SCVA greatly affects patients' clinical journey and healthcare cost.

Risk factors for arteriovenous fistula dysfunction in hemodialysis patients: a retrospective study

Arteriovenous fistula (AVF) is the first choice of vascular access in hemodialysis (HD) patients. However, the correlations between patient factors and the arteriovenous fistula patency remain unclear. Therefore, our study investigates the risk factors associated with AVF dysfunction in HD patients. A total of 233 end-stage renal disease (ESDR) patients who met the study inclusion criteria in the Nephrology Department of Hunan Provincial People's Hospital between December 2020 and June 2022 were included in this study. The baseline demographic, clinical and laboratory parameters were collected at the time of AVF creation and analyzed. Of the 233 ESRD patients, 146 (62.7%) were male and the mean age was 56.11 ± 12.14 (21-82) years. The patients were followed for a median time of 14 months. Kaplan-Meier analysis showed a 6-, 12- and 24-month post-placement survival of 87.1%, 82.8% and 80.7%, respectively. Univariate Cox regression analysis revealed weight (HR, 1.03; P = 0.03) as a predictor for the loss of vascular access functionality. In addition, multivariate Cox regression analysis further demonstrated that sex (HR, 3.41; P = 0.03), weight (HR 1.08; P < 0.01) and phosphorus level (HR: 3.03; P = 0.01) are independent risk factors for AVF dysfunction. AVF dysfunction is highly associated with several risk factors including weight, phosphorus level, and sex. Positive intervention strategies targeting these potential factors, such as weight loss or oral phosphate binders could improve the long-term success of AVF.

Nurses' perceptions of point-of-care ultrasound for haemodialysis access assessment and guided cannulation: A qualitative study

AIM

To explore nurses' perceptions of using point-of-care ultrasound for assessment and guided cannulation in the haemodialysis setting.

BACKGROUND

Cannulation of arteriovenous fistulae is necessary to perform haemodialysis. Damage to the arteriovenous fistula is a frequent complication, resulting in poor patient outcomes and increased healthcare costs. Point-of-care ultrasound-guided cannulation can reduce the risk of such damage and mitigate further vessel deterioration. Understanding nurses' perceptions of using this adjunct tool will inform its future implementation into haemodialysis practice.

DESIGN

Descriptive qualitative study.

METHODS

Registered nurses were recruited from one 16-chair regional Australian haemodialysis clinic. Eligible nurses were drawn from a larger study investigating the feasibility of implementing point-of-care ultrasound in haemodialysis. Participants attended a semistructured one-on-one interview where they were asked about their experiences with, and perceptions of, point-of-care ultrasound use in haemodialysis cannulation. Audio-recorded data were transcribed and inductively analysed.

FINDINGS

Seven of nine nurses who completed the larger study participated in a semistructured interview. All participants were female with a median age of 54 years (and had postgraduate renal qualifications. Themes identified were as follows: (1) barriers to use of ultrasound; (2) deficit and benefit recognition; (3) cognitive and psychomotor development; and (4) practice makes perfect. Information identified within these themes were that nurses perceived that their experience with point-of-care ultrasound was beneficial but recommended against its use for every cannulation. The more practice nurses had with point-of-care ultrasound, the more their confidence, dexterity and time management improved.

CONCLUSIONS

Nurses perceived that using point-of-care ultrasound was a positive adjunct to their cannulation practice and provided beneficial outcomes for patients.

IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE

Haemodialysis clinics seeking to implement point-of-care ultrasound to help improve cannulation outcomes may draw on these findings when embarking on this practice change.

REPORTING METHOD

This study is reported according to the Consolidated Criteria for Reporting Qualitative Research (COREQ).

PATIENT OR PUBLIC CONTRIBUTION

Patients were not directly involved in this part of the study; however, they were involved in the implementation study.

TRIAL AND PROTOCOL REGISTRATION

The larger study was registered with Australian New Zealand Clinical Trials Registry: ACTRN12617001569392 (21/11/2017) https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373963&isReview=true.

Compliance with good practice guidelines for the prevention of vascular access infections: the multi-centre PHYDEL survey in French haemodialysis units

BACKGROUND

French guidelines for the prevention of vascular access infections in a haemodialysis setting were released in 2005. Compliance with these guidelines is currently unknown. The aim of this study was to assess compliance with the guidelines for vascular access infection prevention in French haemodialysis units, and to describe the difficulties reported.

METHODS

A cross-sectional survey was conducted between March and December 2019 in 200 haemodialysis units in France, selected at random. Data were collected via questionnaire, completed by telephone interview with an infection control practitioner. A practice was deemed compliant when >85% of units declared that they always complied with the guidelines.

RESULTS

In total, 103 units (51.5%) agreed to participate. Most practices complied with the guidelines; however, some practices did not reach the 85% compliance threshold for working in pairs when connecting central venous catheter (CVC) lines, performing hand hygiene before disconnecting lines, rinsing antiseptic soap before painting CVC exit site or arteriovenous fistula (AVF) puncture site, allowing antiseptic paint to dry, handling CVC branches with antiseptic impregnated gauze, performing hand hygiene after AVF compression with gloves, wearing protective eyewear when connecting/disconnecting CVC or when puncturing AVF, and wearing a gown when puncturing AVF. The most frequently reported difficulties were understaffing, difficulties with skin preparation because of exit site skin damage, and lack of buttonhole technical expertise.

CONCLUSIONS

Despite good overall compliance, this survey highlights some shortcomings in compliance with infection prevention guidelines, which could be associated with either higher risk of vascular access infection or increased blood-borne virus transmission.

Implementation of a new surveillance system for dialysis-associated infection events in outpatient dialysis facilities in Germany

INTRODUCTION

Patients receiving maintenance haemodialysis are at risk of catheter-related infections. Up to now, there has been no standardized surveillance tool in Germany to evaluate infection events in haemodialysis outpatients. As such, this study aimed to implement an online-based surveillance tool in outpatient dialysis facilities, and to report the first national surveillance data for haemodialysis patients in Germany from October 2019 until September 2021.

METHODS

Outpatient dialysis facilities reported three types of dialysis-associated infection event (DAIE): bloodstream infections, intravenous antimicrobial starts, and local access site infections. Denominator data were provided by the number of haemodialysis treatments at each facility per month. DAIE rates stratified by vascular access type were calculated.

RESULTS

In total, 43 outpatient dialysis facilities reported 723 DAIEs, including 63 bloodstream infections, 439 intravenous antimicrobial starts, and 221 local access site infections. The overall incidence of DAIEs was 0.51 per 1000 dialysis treatments (723/1,413,457) during the surveillance period. The overall incidence of DAIEs was 0.13 per 1000 dialysis treatments among patients with arteriovenous fistulas (AVFs; 126/990,392), 0.41 per 1000 dialysis treatments among patients with arteriovenous grafts (41/99,499), and 1.68 per 1000 dialysis treatments among patients with central venous catheters (CVCs; 535/318,757). The rate ratio of DAIEs between CVC and AVF rates was 13.2 (95% confidence interval 10.9-16.0; P<0.001).

DISCUSSION

These 2-year infection data represent the first standardized data of outpatient dialysis facilities in Germany. Rates of infection were highest among patients with CVCs compared with other vascular access types. This online-based surveillance tool may be helpful to identify effective targets for infection prevention measures in haemodialysis patients.

Alignment Among Patient, Caregiver, and Health Care Provider Perspectives on Hemodialysis Vascular Access Decision-Making: A Qualitative Study

Background

Updates to the Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline for Vascular Access emphasize the "right access, in the right patient, at the right time, for the right reasons." Although this implies a collaborative approach, little is known about how patients, their caregivers, and health care providers engage in vascular access (VA) decision-making.

Objective

To explore how the perspectives of patients receiving hemodialysis, their caregivers, and hemodialysis care team align and diverge in relation to VA selection.

Design

Qualitative descriptive study.

Setting

Five outpatient hemodialysis centers in Calgary, Alberta.

Participants

Our purposive sample included 19 patients receiving maintenance hemodialysis, 2 caregivers, and 21 health care providers (7 hemodialysis nurses, 6 VA nurses, and 8 nephrologists).

Methods

We conducted semi-structured interviews with consenting participants. Using an inductive thematic analysis approach, we coded transcripts in duplicate and characterized themes addressing our research objective.

Results

While participants across roles shared some perspectives related to VA decision-making, we identified areas where views diverged. Areas of alignment included (1) optimizing patient preparedness-acknowledging decisional readiness and timing, and (2) value placed on trusting relationships with the kidney care team-respecting decisional autonomy with guidance. Perspectives diverged in the following aspects: (1) differing VA priorities and preferences-patients' emphasis on minimizing disruptions to normalcy contrasted with providers' preferences for fistulas and optimizing biomedical parameters of dialysis; (2) influence of personal and peer experience-patients preferred pragmatic, experiential knowledge, whereas providers emphasized informational credibility; and (3) endpoints for VA review-reassessment of VA decisions was prompted by access dissatisfaction for patients and a medical imperative to achieve a functioning access for health care providers.

Limitations

Participation was limited to individuals comfortable communicating in English and from urban, in-center hemodialysis units. Few informal caregivers of people receiving hemodialysis and younger patients participated in this study.

Conclusions

Although patients, caregivers, and healthcare providers share perspectives on important aspects of VA decisions, conflicting priorities and preferences may impact the decisional outcome. Findings highlight opportunities to bridge knowledge and readiness gaps and integrate shared decision-making in the VA selection process.

Increased expression of the P2Y12 receptor is involved in the failure of autogenous arteriovenous fistula caused by stenosis

OBJECTIVE

This study investigated the role of the P2Y12 receptor in autogenous arteriovenous fistula (AVF) failure resulting from stenosis.

METHODS

Stenotic venous tissues and blood samples were obtained from patients with end-stage renal disease (ESRD) together with AVF stenosis, while venous tissues and blood samples were collected from patients with ESRD undergoing initial AVF surgery as controls. Immunohistochemistry and/or immunofluorescence techniques were utilized to assess the expression of P2Y12, transforming growth factor-β1 (TGF-β1), monocyte chemotactic protein 1 (MCP-1), and CD68 in the venous tissues. The expression levels of P2Y12, TGFβ1, and MCP-1 were quantified using quantitative reverse transcription-polymerase chain reaction and western blot analyses. Double and triple immunofluorescence staining was performed to precisely localize the cellular localization of P2Y12 expression.

RESULTS

Expression levels of P2Y12, TGFβ1, MCP-1, and CD68 were significantly higher in stenotic AVF venous tissues than in the control group tissues. Double and triple immunofluorescence staining of stenotic AVF venous tissues indicated that P2Y12 was predominantly expressed in α-SMA-positive vascular smooth muscle cells (VSMCs) and, to a lesser extent, in CD68-positive macrophages, with limited expression in CD31-positive endothelial cells. Moreover, a subset of macrophage-like VSMCs expressing P2Y12 were observed in both stenotic AVF venous tissues and control venous tissues. Additionally, a higher number of P2Y12+/TGF-β1+ double-positive cells were identified in stenotic AVF venous tissues than in the control group tissues.

CONCLUSION

Increased expression of P2Y12 in stenotic AVF venous tissues of patients with ESRD suggests its potential involvement in the pathogenesis of venous stenosis within AVFs.

Robotic tomographic ultrasound and artificial intelligence for management of haemodialysis arteriovenous fistulae

BACKGROUND

Arteriovenous fistulae (AVF) and Arteriovenous Grafts (AVG) may present a problematic vascular access for renal replacement therapy (RRT), reliant on recurrent specialist nurse and medical evaluation. Dysfunctional accesses are frequently referred 'out of the dialysis clinic' for specialist sonographic examination, with associated delays potentiating loss of vascular access viability and/or need for emergency intervention. Definitive anatomical and functional diagnostics based in the dialysis unit may help to solve these delays and associated complications.

OBJECTIVES

This publication reports a novel vascular access monitoring concept, Robotic Tomographic Ultrasound (RTU).

RESEARCH DESIGN

Robotic Tomographic Ultrasound incorporates a semi-autonomous, robotic vascular ultrasound system and purpose designed analysis software that can be deployed at the point of care. Three-dimensional scan data, as well as conventional B-Mode and Doppler data are obtained by the system and transferred to a cloud based reporting and analysis software. Scans are remotely annotated and interpreted by a sonographer, with diagnostic data presented securely to clinicians on their preferred web based application/web connected device.

RESULTS

Software developed specifically for pre AVF mapping, maturation and monitoring protocols, analyse the data and then present interpreted results to all caring clinicians to assist with decision making. Vascular access planning can be determined with high confidence with data from the Map module. Maturation data can be presented in line with institutional requirements to the dialysis nurse, facilitating precocious needle access.

CONCLUSION

Robotic Tomographic Ultrasound is a novel approach to vascular access management that may reduce the risk of loss of functional access by regular monitoring with the system; automated alerts guiding clinicians to the need for pre-emptive intervention, and the potential to increase longevity of the vascular access.

Central venous catheter-related complications in older haemodialysis patients: A multicentre observational cohort study

BACKGROUND

Central venous catheters (CVC) remain a commonly used vascular access option in haemodialysis, despite guidelines advising to preferably use arteriovenous fistulae. Compared to younger patients, the risk-benefit ratio of CVC in older patients might be more beneficial, but previous studies mainly focussed on catheter-related bacteraemia and/or assessed tunnelled CVC (TCVC) only. This study's aim was to compare all catheter-related infections and malfunctions in older patients with younger patients using all CVC subtypes.

MATERIALS AND METHODS

We used data from DUCATHO, a multicentre observational cohort study in The Netherlands. All adult patients in whom a CVC was placed for haemodialysis between 2012 and 2016 were included. The primary endpoint was the occurrence of catheter-related infections, comparing patients aged ⩾70 years with patients aged <70 years (reference). As secondary endpoints, catheter malfunctions and catheter removal due to either infection or malfunction were assessed. Using Cox proportional hazards and recurrent events modelling, hazard ratios (HR) with 95% confidence intervals (CI) were calculated with adjustment of prespecified confounders. Additionally, endpoints were assessed for non-tunnelled CVC (NTCVC) and TCVC separately.

RESULTS

A total of 1595 patients with 2731 CVC (66.5% NTCVC, 33.1% TCVC) were included. Of these patients, 1001 (62.8%) were aged <70 years and 594 (37.2%) ⩾70 years. No statistically significant difference was found for the occurrence of catheter-related infections (adjusted HR 0.80-95% CI 0.62-1.02), catheter malfunction (adjusted HR 0.94-95% CI 0.75-1.17) and catheter removal due to infection or malfunction (adjusted HR 0.94-95% CI 0.80-1.11). Results were comparable when assessing NTCVC and TCVC separately.

CONCLUSION

Patients aged ⩾70 to <70 years have a comparable risk for the occurrence of catheter-related infections and catheter malfunction. These findings may help when discussing treatment options with older patients starting haemodialysis and may inform the current debate on the best vascular access for these patients.

Tunnelled central venous catheters for incident haemodialysis patients: a Victorian survey exploring reasons for use

BACKGROUND

Tunnelled central venous catheters (T-CVCs) are used globally as vascular access for patients on haemodialysis (HD) but are associated with increased sepsis, mortality, cost and length of hospitalisation compared with more permanent HD vascular access. The reasons for using T-CVC are varied and poorly understood. A significant and increasing proportion of incident HD patients in Victoria, Australia, have required T-CVC over the last decade.

AIM

To explore reasons for a significant and increasing proportion of incident HD patients in Victoria, Australia, having required T-CVC over the last decade.

METHODS

With rates of starting HD with definitive vascular access consistently below a Victorian quality indicator target of 70%, an online survey was developed to explore reasons why the rate remained lower than desired and to help inform future decisions about this quality indicator. The survey was completed by dialysis access coordinators over an 8-month period and involved all public nephrology services in Victoria.

RESULTS

Of the 125 surveys completed, 101 incident HD patients had no attempt at permanent vascular access prior to T-CVC insertion. For almost half of these (48 patients), there was no active medical decision not to create permanent vascular access prior to commencing dialysis. Reasons for insertion of the T-CVC included deterioration of kidney function faster than anticipated, surgical referral being overlooked, complications related to peritoneal dialysis requiring a change in dialysis modality and changes to initial decisions regarding dialysis modality for kidney failure.

CONCLUSIONS

These survey results provide an opportunity for quality improvement initiatives with respect to dialysis access planning and care.

High pulse pressure predicts primary arteriovenous fistula failure within 1 year

BACKGROUND

The arteriovenous fistula is the preferred access route for hemodialysis, although its high primary failure rate remains a clinical challenge. Multiple studies have attempted to determine the risk factors for primary arteriovenous fistula failure; however, none have identified pulse pressure as a potential predictive marker. High pulse pressure is a surrogate poor arterial compliance endpoint and leads to inferior cardiovascular outcomes. Our aim was to determine whether elevated pulse pressure indicates poor arteriovenous fistula maturation.

METHODS

We retrospectively reviewed 274 patients who underwent an arteriovenous fistula index operation between September 1, 2018 and May 31, 2019. Demographic, clinical data, and operative parameters were collected and analyzed. The maximum follow-up period was 365 days. Arteriovenous fistula failure was defined as the inability to achieve functional use during the follow-up period. We identified risk factors for arteriovenous fistula failure by performing a multivariate logistic regression analysis using backward elimination procedures.

RESULTS

A total of 274 patients were included in the study. The patients' average age was 61.3 ± 14.0 years, approximately half of the patients (n = 161, 58.8%) were male, and the majority had hypertension. At the end of the follow-up period, 68 (24.8%) had arteriovenous fistula failure. The proportion of patients with pulse pressure values of >60 mmHg was significantly higher in the failure group than in the maturation group (66.0% vs 80.9%; p = 0.021). A PP value of >60 mmHg (odds ratio = 2.25; 95% confidence interval = 1.14-4.42; p = 0.019) and coronary artery disease or myocardial infarction (odds ratio = 1.97; 95% confidence interval = 1.01-3.84; p = 0.045) were found to be independent risk factors for primary arteriovenous fistula failure.

CONCLUSIONS

High pulse pressure is an independent risk factor for primary arteriovenous fistula failure.

Arteriovenous fistula self-care behaviors in patients receiving hemodialysis treatment: Association with health literacy and self-care agency

BACKGROUND

Arteriovenous fistula-related self-care behaviors, self-care agency and health literacy are important for vascular access patency, which is vital in the continuation of hemodialysis treatment. The purpose of this study was to determine the arteriovenous fistula-related self-care behaviors of patients receiving chronic hemodialysis treatment and the relationship between these behaviors and their health literacy and self-care agency levels.

METHODS

In this descriptive correlational study, the data were collected from 216 chronic hemodialysis patients.

RESULTS

The rate of the patients who had good self-care behaviors levels was 83.96%. The sociodemographic variables that were significantly related to AVF-related self-care behaviors were education, employment status and age. It was found that the patients who had had AVF for a longer time had better self-care behaviors regarding their management of symptoms and findings (p < 0.05). As the self-care agency of the patients (r = 0.612, p < 0.001) and their health literacy (r = 0.421, p < 0.001) increased, their AVF-related self-care behaviors also increased.

CONCLUSION

Age, education status, health literacy and self-care agency were identified to affect AVF-related self-care behaviors.