Vascular Access Guidelines: Summary, Rationale, and Controversies

Slowly moving the needle away from Fistula First

OBJECTIVE

In 2019, the management of end-stage kidney disease (ESKD) shifted away from "Fistula First" (FF) to "ESKD Life-Plan: Patient Life-Plan First then Access Needs." Indeed, some patients exhibit such excessive comorbidity that even relatively minor vascular surgery may be complicated. The purpose of this study was to retrospectively assess complications and mortality (and delineate operative futility) in patients undergoing arteriovenous fistula (AVF) creation in the FF era.

METHODS

Consecutive AVFs created in a single institution before 2021 were retrospectively reviewed. Operative futility was defined as never-accessed fistula, no initiation of dialysis, failure of access maturation (despite secondary intervention), hemodialysis access-induced distal ischemia requiring ligation, early loss of secondary patency, and/or patient mortality within the first 6 postoperative months.

RESULTS

A total of 401 AVFs were created including radial-cephalic (44%), brachial-cephalic (41%), and brachial-basilic (15%) constructions. Patients exhibited a mean age of 69 ± 15 years; 63% were male, and most (74%) were already being hemodialyzed at the time of fistula creation. Forty-five patients (11%) suffered a cardiac event, and five patients died (1%) within 90 days of their access surgery. Perioperative cardiac events were significantly more common after age 80 (19% vs 8%; P = .004); age >80 years was an independent predictor of major 90-day complications (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.04-3.39; P = .036) and the sole independent predictor of major morbidity defined as cardiopulmonary complications, stroke, or death within the first year (OR, 2.01; 95% CI, 1.24-3.25; P = .004). Operative futility was encountered in 52% of the cohort (n = 208 patients): 40% (n = 160) of primary AVFs failed to mature despite assistance, 19% (n = 77) had lost secondary patency by 6 months, 13% of patients (n = 53) were never started on dialysis after access creation, 4% (n = 16) were dead by 6 months, 2% of AVFs (n = 10) matured but were never accessed, and 2% (n = 9) required ligation for hemodialysis access-induced distal ischemia. Not surprisingly, the sole independent protector against operative futility was that catheter-based dialysis had been established prior to AVF creation (OR, 0.36; 95% CI, 0.22-0.59; P < .01).

CONCLUSIONS

Approximately 50% of primary AVF operations performed in the aggressive FF era were deemed futile. Octogenarians were particularly prone to futility and complications during this era. A paradigm shift, from FF to an "ESKD Life-Plan" will, hopefully, more thoughtfully match vascular access strategies to individual patient needs.

Venous Access: National Guideline and Registry Development (VANGUARD): Advancing Patient-Centered Venous Access Care Through the Development of a National Coordinated Registry Network

There are over 8 million central venous access devices inserted each year, many in patients with chronic conditions who rely on central access for life-preserving therapies. Central venous access device-related complications can be life-threatening and add tens of billions of dollars to health care costs, while their incidence is most likely grossly mis- or underreported by medical institutions. In this communication, we review the challenges that impair retention, exchange, and analysis of data necessary for a meaningful understanding of critical events and outcomes in this clinical domain. The difficulty is not only with data extraction and harmonization from electronic health records, national surveillance systems, or other health information repositories where data might be stored. The problem is that reliable and appropriate data are not recorded, or falsely recorded, at least in part because policy, payment, penalties, proprietary concerns, and workflow burdens discourage completeness and accuracy. We provide a roadmap for the development of health care information systems and infrastructure that address these challenges, framed within the context of research studies that build a framework of standardized terminology, decision support, data capture, and information exchange necessary for the task. This roadmap is embedded in a broader Coordinated Registry Network Learning Community, and facilitated by the Medical Device Epidemiology Network, a Public-Private Partnership sponsored by the US Food and Drug Administration, with the scope of advancing methods, national and international infrastructure, and partnerships needed for the evaluation of medical devices throughout their total life cycle.

Effect of preoperative arterial diameter on hospitalization and mortality in patients undergoing hemodialysis with forearm arteriovenous fistula access

BACKGROUND

As pointed out by the recent Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline for Vascular Access, the current quality of evidence supporting preoperative vascular anatomy and patient outcomes is suboptimal and insufficient to make recommendations. This study assessed arteriovenous fistulas (AVFs) created with different preoperative arterial diameters on hospitalization and mortality rates in patients undergoing hemodialysis at the authors' center.

METHODS

Data from 261 patients who underwent HD between 2017 and 2019 were retrospectively examined. Differences in mortality and hospitalization rates between patients with different preoperative arterial diameters were compared, and risk factors for mortality and hospitalization were analyzed.

RESULTS

Smaller preoperative artery diameter (<2 mm) was associated with all-cause mortality (risk ratio [RR] 1.61 [95% confidence interval (CI) 1.45-1.90]; p < 0.01), and access-related (RR 1.68 [95% CI 1.24-2.44]; p < 0.01), and congestive heart failure (CHF)-related (RR 0.67 [95% CI 0.38-1.01]; p = 0.04) hospitalization. Longer catheter-dependent duration (⩾60 days) was associated with access-related hospitalization (RR 1.48 [95% CI 1.07-2.11]; p = 0.03), and higher postoperative brachial artery blood flow (⩾1500 mL/min) was associated with CHF-related hospitalization (RR 1.58 [95% CI 1.02-2.29]; p < 0.01). Higher postoperative brachial artery blood flow (⩾1500 mL/min) was associated with all-cause mortality (hazard ratio [HR] 1.20 [95% CI 1.09-2.32]; p = 0.04), whereas preoperative artery diameter (HR 0.98 [95% CI 0.93-1.86]; p = 0.08) and catheter-dependent duration (HR 1.06 [95% CI 0.47-2.13]; p = 0.82) were not associated with all-cause mortality.

CONCLUSION

In this cohort, smaller preoperative artery diameter was associated with all-cause and access-related hospitalizations, while a larger preoperative artery and higher postoperative brachial blood flow were associated with CHF-related hospitalization. However, only higher postoperative brachial blood flow was associated with all-cause mortality.

Strategies to Prevent Infections in Dialysis Patients

Infections are the second leading cause of death among patients with end-stage kidney disease, behind only cardiovascular disease. In addition, patients on chronic dialysis are at a higher risk for acquiring infection caused by multidrug-resistant organisms and for death resulting from infection owing to their likelihood of requiring treatment that involves invasive devices, their frequent exposure to antibiotics, and their impaired immunity. Vascular access is a major risk factor for bacteremia, hospitalization, and mortality among hemodialysis (HD) patients. Catheter-related bacteremia is the most severe central venous catheter (CVC)-related infection and increases linearly with the duration of catheter use. Given the high prevalence of CVC use and its direct association with catheter-related bacteremia, which adversely impacts morbidity and mortality rates among HD patients, several prevention measures aimed at reducing the rates of CVC-related infection have been proposed and implemented. As a result, a large number of clinical trials, systematic reviews, and meta-analyses have been conducted to assess the effectiveness, clinical applicability, and long-term adverse effects of such measures. Peritoneal dialysis chronic treatment without the occurence of peritonitis is rare. Although most cases of peritonitis can be treated adequately with antibiotics, some cases are complicated by hospitalization or a temporary or permanent need to abstain from using the peritoneal dialysis catheter. Severe and long-lasting peritonitis can lead to peritoneal membrane failure, requiring the treatment method to be switched to HD. Some measures as patients training, early diagnosis, and choice of antibiotics can contribute to the successful treatment of peritonitis. Finally, medical directors are key leaders in infection prevention and are an important resource to implement programs to monitor and improve infection prevention practices at all levels within the dialysis clinic.

Embolization in Pediatric Patients: A Comprehensive Review of Indications, Procedures, and Clinical Outcomes

Embolization in pediatric patients encompasses a large spectrum of indications, ranging from the elective treatment of congenital diseases of the cardiovascular system to the urgent management of acute hemorrhagic conditions. In particular, the endovascular treatment of central and peripheral vascular malformations and hypervascular tumors represents a wide chapter for both congenital and acquired situations. Thanks to the progressive availability of low-profile endovascular devices and new embolic materials, the mini-invasive approach has gradually overtaken surgery. In this review, the main embolization procedures will be illustrated and discussed, with a focus on clinical indications and expected outcomes. The most recent mini-invasive techniques will be described, with hints on the cutting-edge devices and embolic materials.

Comparison of catheters or new arteriovenous fistulas for commencement of haemodialysis in pregnant women with chronic kidney disease: an international observational study

Background

Evidence surrounding vascular access options for commencing dialysis in pregnancy complicated by chronic kidney disease (CKD) is limited. Creation of new arteriovenous fistulas (AVFs) in pregnant women is rare.

Methods

Retrospective cohort study of approaches to vascular access in pregnancy in centres in Australia, the United Kingdom (UK) and Canada (2002–2018).

Results

Twenty-three women with advanced CKD commenced dialysis in pregnancy (n = 20) or planned to commence (n = 3). Access at dialysis start was a tunnelled catheter (n = 13), temporary catheter (n = 1), AVF created pre-conception but used in pregnancy (n = 3) and AVF created during pregnancy (n = 3). No women commencing dialysis with an AVF required a catheter. No differences in perinatal outcomes were observed comparing AVFs and catheters at dialysis commencement. No AVFs were created in pregnancy in Canadian women. From Australia and the UK, 10 women had a new AVF created in pregnancy, at median gestation 14.5 weeks (IQR 12.5, 20.75). Four women still needed a catheter for dialysis initiation and 3 eventually used the new AVF. Six AVFs were successfully used in pregnancy at median gestation 24 weeks (IQR 22.5, 28.5), 2 were successfully created but not used and 2 had primary failure. No catheter-associated complications were identified except one episode of catheter-related sepsis.

Conclusions

Catheter-related complications were minimal. In selected women, with sufficient pre-planning, an AVF can be created and successfully used during pregnancy to minimise catheter use if preferred. Pre-conception counselling in advanced CKD should include discussing vascular access options reflecting local expertise and patient preferences.

Graphic abstract

The association between the locations of arteriovenous fistulas and patency rates: A systematic review and meta-analysis

BACKGROUND

The arteriovenous fistulas (AVF) continue to be the most prevalent type of vascular access for hemodialysis (HD). However, the appropriate locations of AVF are controversial. We conducted the meta-analysis to investigate the differences in patency between upper-arm and forearm AVF.

METHODS

PubMed, EMBASE, CENTRAL, and ISI Web of Science were searched to identify studies with differences in AVF patency at different locations. Reviewers searched the database, screened studies according to inclusion criteria, and conducted Meta-analysis.

RESULTS

A total of 12 studies involving 3437 patients were selected. Pooled data showed that primary patency (PP) of AVF were higher in upper-arm than forearm at 1 and 2 years (odds ratio [OR] = 1.54, p = 0.0005; OR = 2.45, p = 0.001), but the differences in cumulative patency (CP) were not statistically significant at 1 and 2 years (OR = 2.10, p = 0.08; OR = 2.16, p = 0.1). The differences in PP and CP between upper-arm and forearm AVF in patients older than 65 years were not statistically significant at 1 (OR = 1.61, p = 0.05; OR = 2.05, p = 0.17) and 2 years (OR = 3.40, p = 0.13; OR = 1.38, p = 0.16). In Asian patients, the differences in PP and CP between upper-arm and forearm AVF were not statistically significant at 1 (OR = 1.17, p = 0.41; OR = 1.02, p = 0.94) and 2 years (OR = 2.95, p = 0.08; OR = 1.23, p = 0.41).

CONCLUSIONS

In this study, the CP of upper-arm and forearm AVF was similar in overall population. There was no difference in PP and CP of AVF between upper-arm and forearm in Asian population or the elderly. The forearm AVF could be consider to be the first choice. for Asian patients or the elderly.

Repeated Endovascular Interventions Are Worthwhile, Even After Thrombosis, to Maintain Long-Term Use of Autogenous Dialysis Fistulas

OBJECTIVES

Patients often require multiple access re-interventions to improve fistula patency and the overall usable lifespan of autogenous arteriovenous fistula (aAVF). There is no consensus on the appropriate number of re-interventions after which an access should be abandoned and new access placed. We evaluated whether repeated endovascular interventions for failing/failed aAVF are worthwhile or futile.

METHODS

A retrospective review was performed on aAVFs created between 2009-2014. Fistula function was evaluated until January 2017. Functional fistula patency (FFP) was defined as the total time of functional fistula use for hemodialysis, from time of cannulation to time of measurement or fistula abandonment, including all interventions performed to maintain/reestablish patency. Primary outcomes were FFP duration and number of post-dialysis interventions.

RESULTS

The study included 163 patients. Mean age was 67 (SD = 15.03). The only variable statistically different between functional fistulas and abandoned fistulas was obesity (p = 0.03). At the end of the study period, 145 (89.0%) patients continued to have functional fistulas, and 73 (44.8%) patients died, but had functional fistulas at time of death. Median FFP for the functional group was 3.18 years (range 0.01-7.01 years) and median number of interventions was 1 (range 0-13). In 18 patients (11%), the fistula was abandoned, most commonly due to thrombosis (47.1%), followed by infection (23.5%). No fistula was abandoned because of an unacceptable rate of reintervention. Median FFP in the abandoned group was 0.91 years (range 0.03-5.30 years), and median number of interventions was 0 (range of 0-5).

CONCLUSIONS

Through repeated interventions on aAVFs, none of the patients in our study exhausted all hemodialysis access options prior to transplantation, death or loss to follow-up. These results may indicate repeated and/or more frequent revisions do not negatively affect the FFP nor do they increase the overall risk for abandonment of aAVFs.

Artery to vein configuration of arteriovenous fistula improves hemodynamics to increase maturation and patency

Arteriovenous fistulae (AVF) are the preferred mode of hemodialysis access, but 60% of conventional [vein-to-artery (V-A)] AVF fail to mature, and only 50% remain patent at 1 year. We previously showed improved maturation and patency in a pilot study of the radial artery deviation and reimplantation (RADAR) technique that uses an artery-to-vein (A-V) configuration. Here, we show that RADAR exhibits higher rates of maturation, as well as increased primary and secondary long-term patencies. RADAR is also protective in female patients, where it is associated with decreased reintervention rates and improved secondary patency. RADAR and conventional geometries were compared further in a rat bilateral carotid artery-internal jugular vein fistula model. There was decreased cell proliferation and neointimal hyperplasia in the A-V configuration in male and female animals, but no difference in hypoxia between the A-V and V-A configurations. Similar trends were seen in uremic male rats. The A-V configuration also associated with increased peak systolic velocity and expression of Kruppel-like factor 2 and phosphorylated endothelial nitric oxide synthase, consistent with improved hemodynamics. Computed tomography and ultrasound-informed computational modeling showed different hemodynamics in the A-V and V-A configurations, and improving the hemodynamics in the V-A configuration was protective against neointimal hyperplasia. These findings collectively demonstrate that RADAR is a durable surgical option for patients requiring radial-cephalic AVF for hemodialysis access.

Factors influencing the long-term outcome of tunneled hemodialysis catheters

PURPOSE

To review the incidence and type of tunneled hemodialysis catheter (THC) complications in a large cohort of patients with end-stage renal disease. Additionally, the longevity of the THC and factors predicting high risk for catheter complications were assessed.

MATERIAL AND METHODS

Between August 2009 and December 2016, a cohort of 538 patients underwent primary THC insertion; in 119 patients, THC was inserted after failed arteriovenous fistula or graft. Patients without available clinical follow-up data (n = 67) were excluded for further analysis. The Charlson comorbidity index (CCI) was calculated for each patient. The cumulative incidence function (CIF) was used for THC overall longevity, while Cox proportional hazards models were used for risk factor analysis.

RESULTS

In 352 patients, THC was inserted in a virgin neck. THC-related complications were observed in n = 104 (29.55%) of the patients. Infection occurred in n = 38 (10.80%) and malfunction, related to thrombosis or mechanical damage, in n = 45 (12.78%). Removal of the THC for the purpose of switching to alternative dialysis methods was planned in n = 135 (38.4%). The remaining patients were still alive with a functioning THC (n = 18; 5.11%) or died (n = 95; 27%) with a functioning THC. The THC survival rate was 82.67%, 78.13%, 74.15%, 72.96%, 71.02%, and 70.63% on follow-up after 6 months, and after 1-5 years, respectively. Gender, CCI, age, and site of placement of the catheter were found not to affect the life of the catheter.

CONCLUSION

The overall complication rate in primary inserted THC was nearly 30% and mainly related to infection and malfunction. THC survival was more than 70% after 5 years, which supports its use for permanent dialysis access, irrespective of gender, CCI, age, and jugular side of THC placement.

Arteriovenous fistulas for hemodialysis: Brief review and current problems

The number of people worldwide living with end-stage renal disease is increasing. Arteriovenous fistulas are the preferred method of vascular access in patients who will require hemodialysis. As the number of patients with arteriovenous fistulas grows, the role of physicians who intervene who maintain and salvage these fistulas will grow in importance. This review aims to familiarize practitioners with the rationale for arteriovenous fistula creation, the detection of fistula dysfunction, and the state of the art on fistula maintenance and preservation. Current controversies are briefly reviewed.

The Role of Immunosuppressive Therapy in Aneurysmal Degeneration of Hemodialysis Fistulas in Renal Transplant Patients

BACKGROUND

Venous aneurysms are long-term complications of arteriovenous fistula (AVF) for hemodialysis with an estimated incidence rate of around 5-6%. The purpose of our study is to investigate the role of immunosuppressive therapy in the development of AVF aneurysms in renal transplant patients, and to determine whether AVF closure following transplantation is necessary.

METHODS

Forty-six patients with symptomatic venous AVF aneurysms underwent ligation and resection of their fistulas between January 2013 and January 2020. Immunohistochemical expression of CD3, CD4, and CD8 was assessed on the surgical specimens to characterize lymphocytic infiltrate in the aneurysm wall. Patients were subdivided into "Group A"-kidney transplant patients undergoing immunosuppressive therapy which was comprised of 39 patients and "Group B"-patients who had not undergone kidney transplant which was comprised of 7 patients. The 2 groups did not significantly differ in age, sex nor risk factors for aneurysms.

RESULTS

Group A showed a significantly higher aneurysm diameter (P < 0.0001), mean flow (P < 0.0001) and required a longer duration of surgery (P = 0.0007). A CD3+ lymphocytic infiltrate was significantly more common in Group A than in the Group B (90% vs 29%; P < 0.001). No significant differences in localization (adventitia, media or intima) and type (CD4+ vs CD8+) of lymphocytes were found between the 2 groups.

CONCLUSION

AVF venous aneurysms were significantly larger and with a more intense T-lymphocytic infiltrate in patients undergoing immunosuppressive therapy. This finding suggests that immunosuppressive therapy plays a role in aneurysm formation, supporting the need for AVF closure in patients with an estimated low risk of rejection.

Association Between Implementation Of Novel Therapies And Improved Survival In Patients Starting Hemodialysis: The Swedish Renal Registry 2006-2015

BACKGROUND

The recent years have witnessed significant therapeutic advances for patients on hemodialysis. We evaluated temporal changes in treatments practices and survival rates among incident hemodialysis patients.

METHODS

Observational study of patients initiating hemodialysis in Sweden 2006-2015. Trends of hemodialysis-related practices, medications, and routine laboratory biomarkers were evaluated. The incidence of death and major cardiovascular events (MACE) across calendar years were compared against the age-sex-matched general population. Via Cox regression, we explored whether adjustment for implementation of therapeutic advances modified observed survival and MACE risks.

RESULTS

Among 6,612 patients, age and sex were similar, but the burden of co-morbidities increased over time. The proportion of patients receiving treatment by hemodiafiltration, >3 sessions/week, lower ultrafiltration rate, and working fistulas increased progressively, as did use of non-calcium phosphate binders, cinacalcet, and vitamin D3. The standardized 1-year mortality decreased from 13.2% in 2006/07 to 11.1% in 2014/15. The risk of death decreased by 6% (HR 0.94, 95% CI 0.90-0.99) every two years, and the risk of MACE by 4% (HR 0.96; 0.92-1.00). Adjustment for changes in treatment characteristics abrogated these associations (HR 1.00; 0.92-1.09 for death and 1.00; 0.94-1.06 for MACE). Compared with the general population, the risk of death declined from 6 times higher 2006/2007 [standardized incidence rate ratio, sIRR 6.0 (5.3-6.9)], to 5.6 higher 2014/15 [sIRR 5.57 (4.8-6.4)].

CONCLUSIONS

Gradual implementation of therapeutic advances over the last decade was associated with a parallel reduction in short-term risk of death and MACE among hemodialysis patients.

Spontaneous Dislodgement of Tunneled Dialysis Catheters after De Novo versus Over-The-Wire-Exchange Placement

PURPOSE

To evaluate dislodgement of tunneled dialysis catheters (TDCs) in de novo (DN) placement with ultrasound versus over-the-wire exchange (OTWE).

MATERIALS AND METHODS

Data were collected retrospectively on all TDC placements at this institution from 2001 to 2019 and were excluded if no removal date was recorded or if dwell time was more than 365 days. Information on TDC brand, placement, insertion/removal, and removal reason were collected. Multiple logistic regression evaluated factors associated with TDC dislodgement. DN placement and OTWE were compared for rate of dislodgement (generalized estimating equations method) and TDC dwell time (survival analysis).

RESULTS

In total, 5328 TDCs were included with 66% (3522) placed DN and 32% (1727) via OTWE. Mean dwell time was 65 ± 72 days, and dislodgement occurred in 4% (224). TDC dislodgement rates in the DN and OTWE groups were 0.48 and 0.93 per 1000 catheter days, respectively. Brand (Ash Split vs. VectorFlow), placement technique (OTWE vs. DN), laterality (left vs. right), and site (left vs. right internal jugular vein) were significant predictors of dislodgement. OTWE placement exhibited 1.7 times the odds of dislodgement (95% confidence interval, 1.2-2.6; P = .004) compared to DN and had significantly higher probability of dislodgement across time (hazard ratio = 2.0; P < .001) compared to DN. Dislodgement rates for OTWE vs. DN were 8% vs. 3% (3 months), 13% vs. 6% (6 months), and 38% vs. 17% (1 year).

CONCLUSIONS

TDC spontaneous dislodgement rates were significantly and consistently higher after OTWE compared to DN placement. These data support more careful attention to catheter fixation after OTWE placement.

"Outcomes of arteriovenous fistulae cannulation in the first 6 weeks of use: A retrospective multicenter observational study"

BACKGROUND

Arteriovenous fistula (AVF) management for haemodialysis (HD) is one of the most challenging aspects of clinical care. A successful cannulation outcome when an AVF or arteriovenous graft (AVG) is used for the first time can be influenced by many factors, including access maturity, staff skill, and patient factors. This study examined AVF/AVG outcomes at initiation of HD across two major metropolitan public hospitals.

METHODS

Electronic medical records were reviewed to collect data retrospectively for a cohort of all newly commencing ESRD HD starts during 2018 to identify cannulation outcomes in the first 6 weeks.

RESULTS

Of the 117 patients included, AVG use was low (5%). Twenty-four percent of patients required a surgical intervention to salvage a poorly functioning AVF prior to commencing HD. About 32.5% of the cohort had an uneventful start with all successful cannulations. For the remainder of the cohort the number of treatments with unsuccessful cannulation ranged from 1 to 4 or more. About 36% required a surgical intervention for a poorly functioning AVF after commencing HD. Commencing HD with a CVC is associated with a lower likelihood of subsequent successful cannulation (p < 0.001).

CONCLUSION

Even in experienced centres, a subset of patients experienced complicated cannulation in the first 6 weeks of HD. Several areas of improvement could be considered for these patients; timely referral for access creation, post-operative surveillance to ensure AVF maturation inclusive of duplex ultrasonography, gentle induction using small gauge needles and low blood flows, and consideration of a single needle HD initiation pathway.

Case report of a large cephalic vein aneurysm inducing heart failure in a renal transplant patient with radio-cephalic fistula for haemodialysis

INTRODUCTION

The autologous arteriovenous fistula (AVF) is considered the best vascular access for haemodialysis in patients with chronic kidney disease but in time can lead to several complications.

PRESENTATION OF A CASE

Herein we describe a case of a large cephalic vein aneurysm causing heart failure in a renal transplant patient being treated with radio-cephalic AVF for haemodialysis. The patient was judged to be at very high risk for potential catastrophic rupture of the aneurysm and his cardiac function was deteriorating so a surgical resection was offered. Under general anesthesia, a longitudinal incision was performed on the volar side of the forearm and the anastomotic junction was ligated. The cephalic vein aneurysm was isolated and a total resection of the vein, up to the joint of the elbow, was carried out. A specimen was also submitted for histological and immunohistochemical analysis.

DISCUSSION

At present no clear indications pertaining to the need to close an AVF after kidney transplantation exist. Some authors recommend a closing of the fistula in patients with stable renal function to prevent the onset of complications, while others advise never to close the asymptomatic fistula in order to preserve vascular access for haemodialysis in case of graft failure.

CONCLUSION

Based on our clinical experience, we suggest not ligating vascular access during the first year following transplantation with the exception of patients needing emergent closure. Otherwise, surgical closure to prevent the onset of complications could be considered a viable option in the following subset of patients: those who are 3 or more years from transplantation with good and stable renal function, those with a significant growth of venous aneurysms or have a high AVF flow rate or are young patients.

MDCT angiography of emergent, non-traumatic, upper extremity vascular lesions

Timely, accurate diagnosis of upper extremity vascular pathology is critical for successful clinical and surgical management. Although the vast majority of upper extremity vascular injury is due to trauma, physicians in the emergency setting, including radiologists, must be familiar with vascular lesions from iatrogenic injury, thromboembolic disease, vascular malformations, and vasculitis. Non-invasive diagnostic imaging with multidetector CT (MDCT) angiography is often employed in the emergency department to evaluate patients with suspected vascular pathology of the upper extremity. Maximum intensity projection and volume rendering technique are two methods that are useful for evaluating vasculature. In addition, dual-energy MDCT is useful in that it allows for the generation of iodine-selective images and bone subtracted images. These techniques can be used to create images that simulate catheter angiograms. In this article, we will discuss the role of MDCT angiography in the diagnosis and management of emergent non-traumatic vascular lesions of the upper extremity.

Upper Arm Arteriovenous Grafts are Superior over Forearm Arteriovenous Grafts in Upper Extremity Dialysis Access

BACKGROUND

In this study, we compared the outcomes of forearm arteriovenous grafts (AVGs) and upper arm AVGs in a large, prospectively collected data set, which represents real-world experience with upper extremity prosthetic dialysis access, to determine if there are clinically significant differences in the upper arm and forearm positions.

METHODS

We identified 2,063 patients who received upper extremity AVGs within the Vascular Quality Initiative data set (2010-2018). Axillary to axillary upper arm AVGs were excluded (n = 394) from the analysis. The main outcome measures were primary and secondary patency rates at 12 months. Other outcomes were 6-month wound infection, steal syndrome, and arm swelling. The log-rank test was used to evaluate patency loss using a Kaplan-Meier analysis. Cox proportional hazards models were used to examine adjusted association between locations (forearm and upper arm) and outcomes.

RESULTS

There were 1,160 forearm AVGs and 509 upper arm brachial artery AVGs in the study cohort. Patients with forearm AVGs were more likely to have a body mass index > 30 (45% vs. 38%, P = 0.013), no history of previous access (73% vs. 63%, P < 0.001), and underwent local-regional anesthesia (56% vs. 43%, P < 0.001). The 12-month primary patency (51.5% vs. 62.9%, P < 0.001) and secondary patency (76.4% vs. 89.1%, P < 0.001) were significantly lower for forearm AVGs. Wound infection, steal syndrome, and arm swelling were similar between forearm AVGs and upper arm AVGs at the 6-month follow-up. In multivariable analysis, the primary patency loss (adjusted hazard ratio (aHR) 1.66, 95% confidence interval (CI) 1.33-2.01, P < 0.001) and 12-month secondary patency loss (aHR 2.71, 95% CI 1.84-3.98, P < 0.001) were significantly higher for forearm AVGs at 12 months.

CONCLUSIONS

From this observational study of the Vascular Quality Initiative data set, the primary and secondary patency rates were superior for upper arm brachial artery AVGs compared with forearm AVGs.

Use of blood temperature monitor with Twister device for the surveillance of vascular access in maintenance hemodialysis: Comparison with Doppler ultrasonography

BACKGROUND

Regular monitoring of vascular access in patients on maintenance hemodialysis is important to detect early vascular access complications. We compared vascular access blood flow determined by blood temperature monitor and Doppler ultrasonography to evaluate the usefulness of blood temperature monitor.

METHODS

In total, 70 patients on maintenance hemodialysis were enrolled from three dialysis centers. Vascular access blood flow was measured thrice at 6-month intervals using Doppler ultrasonography to determine arterial inflow (Q-DUa), venous outflow (Q-DUv), and flow between punctures (Q-DUb) using BTM® (Q-BTM). Twister® was placed between the hemodialysis needle and blood lines, allowing simple reversal of flow without stopping the hemodialysis pump.

RESULTS

In total, 203 measurements were recorded, with median values (interquartile range) for Q-BTM, Q-DUa, Q-DUv, and Q-DUb of 1139.0 (868.0-1588.0) mL/min, 960.3 (658.7-1380.4) mL/min, 946.0 (552.0-1515.0) mL/min, and 1067.7 (544.8-1635.0) mL/min, respectively. For all measurements, the mean intraclass correlation coefficients were 0.52 (95% confidence interval, 0.36-0.64) for Q-DUa; 0.37 (95% confidence interval, 0.15-0.53) for Q-DUv; and 0.45 (95% confidence interval, 0.26-0.59) for Q-DUb. Analysis of a receiver operating characteristics curve yielded a cut-off of 627 mL/min for Q-BTM to predict stenosis.

CONCLUSION

In patients on maintenance hemodialysis, blood flow measured by blood temperature monitor moderately correlated with Doppler blood flow. It was more related to arterial inflow than venous outflow or flow between punctures. The blood temperature monitor method was not inferior to Doppler ultrasonography. Therefore, blood temperature monitor could be recommended for routine vascular access monitoring because it can be done quickly without interrupting dialysis.

Hemodialysis arterio-venous graft design reducing the hemodynamic risk of vascular access dysfunction

Although arterio-venous grafts (AVGs) represent the second choice as permanent vascular access for hemodialysis, this solution is still affected by a relevant failure rate due to graft thrombosis, and development of neointimal hyperplasia (IH) at the distal vein. As a key role in these processes has been attributed to the abnormal hemodynamics establishing in the distal vein, the optimization of AVGs design aimed at minimizing flow disturbances would reduce AVG hemodynamic-related risks. In this study we used computational fluid dynamics to investigate the impact of alternative AVG designs on the reduction of IH and thrombosis risk at the distal venous anastomosis. The performance of the newly designed AVGs was compared to that of commercially available devices. In detail, a total of eight AVG models in closed-loop configuration were constructed: two models resemble the commercially available straight conventional and helical-shaped AVGs; six models are characterized by the insertion of a flow divider (FD), straight or helical shaped, differently positioned inside the graft. Unfavorable hemodynamic conditions were analyzed by assessing the exposure to disturbed shear at the distal vein. Bulk flow was investigated in terms of helical blood flow features, potential thrombosis risk, and pressure drop over the graft. Findings from this study clearly show that using a helically-shaped FD located at the venous side of the graft could induce beneficial helical flow patterns that, minimizing flow disturbances, reduce the IH-related risk of failure at the distal vein, with a clinically irrelevant increase in thrombosis risk and pressure drop over the graft.

Influence of cephalic vein dilation on arteriovenous fistula maturation in patients with small cephalic veins

A substantial limitation of dialysis fistulas is their high primary failure rate due to nonmaturation. Various studies have documented that patients with larger vein diameters exhibit reduced risks for nonmaturation. Nevertheless, some patients have small veins. Few studies have focused on patients with small veins. We hypothesize that sufficient venous dilation contributes to fistula maturation. Therefore, we studied the influence of cephalic vein dilation on fistula maturation in patients with small veins.Patients with small cephalic veins (diameter <2 mm) undergoing initial arteriovenous fistulae (AVF) operation were included. A total of 72 patients were enrolled in this study. A prospective study was performed, and the patients were followed for 6 weeks after surgery. Preoperative and postoperative duplex ultrasound mapping of veins was performed, and dilation of the cephalic vein was evaluated.The fistula maturation rate was 44.44%. Multivariate logistic regression analysis revealed a significant relationship between fistula maturation and preoperative cephalic vein dilation. Based on the results of ROC analysis, the fistula maturation rate in patients with vein dilation greater than or equal to the cut-off was 57.14% in the training data set and 54.55% in the testing data set. The independent influencing factors for fistula maturation were used to establish a combined index with logistic regression analysis. The fistula maturation rate in patients with combined indexes greater than or equal to the cut-off was 80.95% in the training data set and 77.78% in the testing data set.Our results demonstrated that preoperative venous dilation was associated with AVF maturation. For patients with small veins, venous distensibility needs to be carefully assessed before surgery, as it may be a better predictor of AVF maturation than venous diameter.

Evaluation of upper limb superficial venous percussion as a sign of anatomical location and venous permeability. A comparative study of superficial venous percussion to ultrasound findings on non-renal patients and on chronic kidney disease patients

METHODS

An analytical cross-sectional study with 70 individuals divided into two groups. Group A consisted of 35 volunteers who were being preoperatively prepared for the construction of arteriovenous fistula. Group B consisted of 35 non-renal patients selected by convenience. Each participant underwent physical examination, including venous percussion, of the dominant upper limb and then ultrasound. Interobserver agreement was assessed between a trained vascular surgeon performing percussion and fourth-year medical student. Accuracy, sensitivity, specificity, positive predictive value and negative predictive value of percussion were determined in relation to ultrasound. The agreement between the methods, venous percussion and venous duplex ultrasound was also evaluated by the Kappa index.

RESULTS

The overall interobserver agreement for the percussion was 0.74 (95% CI 0.632 to 0.851). It was observed that the results were more favorable in the cephalic vein than in the basilic vein, emphasizing that the cephalic is more used in venous punctures, because of its anatomical location and visibility, and in fistula construction. The 35 percussions of the cephalic forearm vein in Group A resulted in a sensitivity of 1.0 (95% CI 0.63 to 1.00), specificity of 0.96 (95% CI 0.81 to 1.00), a positive predictive value of 0.89(95% CI 0.52 to 1.00) and a negative predictive value of 1.00 (95% CI 0.87 to 1.00), with an accuracy of 0.97 (95% CI 0.85 to 1.00) and Kappa index of 0.92 (95% CI 0.77 to 1.00) in relation to ultrasound. Overall, when all venous segments were analyzed in group A, the Kappa index of agreement between the percussion and the ultrasonography reached 0.56 (95% CI 0.401 to 0.72). All venous segments in Group A had a sensitivity of 0.54 (95% CI 0.37 to 0.70) and a specificity of 0.96 (95% CI 0.90 to 0.99). When all venous segments were analyzed in group B, the Kappa index of agreement between the percussion and the ultrasonography reached 0.48 (95% CI 0.34 to 0.62). All venous segments in Group B had a sensitivity of 0.70 (95% CI 0.59 to 0.79) and a specificity of 0.82 (95% CI 0.69 to 0.91).

CONCLUSION

Venous percussion of the upper limbs has a high positive predictive value and high specificity, when compared to ultrasound as a way to evaluate the patency and adequacy of the cephalic vein. Although there is not enough evidence to preclude ultrasound, percussion should definitely be included in the traditional physical exam evaluation of upper limbs superficial veins.

Evaluation of hemodynamic impact of absorbable sutures in native arteriovenous fistulas: A retrospective study

One of the major causes of arteriovenous fistula failure is the venous stenosis due to aggressive neointimal hyperplasia. The aim of the study was to assess the arteriovenous fistula maturation comparing absorbable sutures and non-absorbable ones in native vessels. Surgeries performed during a period of 24 months by a single team of expert surgeons were evaluated. Surgeries that met the inclusion criteria, namely, age ⩾ 18 years and radio-cephalic arteriovenous fistula, were considered. According to type of suture, patients were classified as Max group (absorbable suture) and Prol group (non-absorbable). Data pertaining to 70 patients were collected; 51% were men and the mean age was 73 ± 12 years. In Max group, an increasing blood flow was observed during the first 4 weeks without post-operative complications. In Prol group, six patients had thrombosis that resulted in vascular access failure. After the first week, the duplex Doppler ultrasound of both groups showed a regular arteriovenous fistula maturation, with an increase of blood flow rate. Although pre-operative post-tourniquet mean vein diameters of Max group were not adequate, the mean vein diameter and mean blood flow rate increased after 4 weeks, respectively. On the contrary, in Prol group, mean vein diameters and blood flow rate decreased. The maturation of arteriovenous fistula and its functional performance were not altered by the type of suture (absorbable/non-absorbable). Absorbable sutures were associated with good results considering arteriovenous fistula maturation.

Cefazolin-gentamicin versus taurolidine-citrate for the prevention of infection in tunneled central catheters in hemodialysis patients: A quasi-experimental trial

BACKGROUND

Catheter-related bloodstream infection (CR-BSI) is one of various complications related to hemodialysis (HD). As a result of the high rate of infection, the use of lock solutions for the prevention of CR-BSI has been studied. However, adverse effects of lock solution, such as increased emergence of strains resistant to antibiotics, which is an important concern, need to be investigated further. The aim of this study was to compare the efficacy of lock solution using a combination of cefazolin and gentamicin versus taurolidine and citrate in reducing CR-BSI in patients undergoing HD and to identify any adverse effects.

METHODS

A prospective observational study was performed at two dialysis centers. Patients using new tunneled central venous catheters (CVC) for HD were included. Patients with a tunneled CVC were assigned to receive either antibiotic lock solution (group 1: gentamicin 7mg/ml+cefazolin 12mg/ml+heparin 3500IU/ml) or lock solution with TauroLock-Hep500 (group 2: taurolidine citrate 4%+heparin 500 IU/ml) during the inter-dialysis period. The patients were allocated to these groups according to the hemodialysis center they were attending.

RESULTS

A total of 145 CVCs were implanted in 127 patients and were followed for 15 months: 77 CVCs (65 patients) were placed in group 1 and 68 CVCs (62 patients) in group 2. There was no difference between the two groups with regard to CR-BSI (events per 1000 catheter-days: group 1=0.79, group 2=1.10; p=0.18) or exit site infection rates (events per 1000 catheter-days: group 1=2.45, group 2=1.83; p=0.37). The groups differed in ESI pathogens, with gram-positive oxacillin-resistant pathogens more frequent in group 1 (31.8% vs. 5.0%; p=0.003). The two groups were similar in mechanical complications. In the Cox regression analysis, the internal jugular vein site was a protective factor for all catheter removal complications (hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.19-0.91) and mechanical complications (HR 0.16, 95% CI 0.065-0.41); only ESI was a risk factor for all catheter removal complications (HR 1.79, 95% CI 1.04-3.07) and mechanical complications (HR 5.64, 95% CI 1.65-19.3).

CONCLUSIONS

The efficacy of both lock solutions was similar in preventing infections related to tunneled CVCs for HD. However, there were more oxacillin-resistant strains in patients who received antibiotic lock solution. Further studies are required to determine the optimal drug regimen and concentrations for lock solution and the associated adverse effects.

Forearm loop arteriovenous grafts preserve and may create new upper arm access sites

INTRODUCTION

This study evaluated the mid-term patency of forearm loop arteriovenous grafts and the dilation of previously inadequate upper arm basilic and cephalic veins after failed forearm loop arteriovenous graft.

METHODS

All access procedures from September 2009 to December 2015 were reviewed. Vein mapping measurements were used to determine whether there was "adequate" upper arm cephalic and/or basilic vein, defined as ⩾3 mm by duplex ultrasound, at the time of forearm loop arteriovenous graft creation. Outcomes of forearm loop arteriovenous graft were compared with upper arm arteriovenous fistula, and primary and cumulative patencies were evaluated.

RESULTS

Thirty-eight forearm loop arteriovenous grafts and 278 upper arm arteriovenous fistulas were created. In the forearm loop arteriovenous graft cohort, nine were inserted with adequate upper arm vein, group A, and 29 were inserted with inadequate upper arm vein, group B. Cumulative patency was lower for forearm loop arteriovenous graft compared with upper arm arteriovenous fistula at 6 months, 1 year, and 2 years (67% vs 91%, 61% vs 85%, and 49% vs 80%, respectively, P < .01). Comparison of group A forearm loop arteriovenous graft and upper arm arteriovenous fistula did not show a statistical difference in cumulative patency at 6 months, 1 year, and 2 years (P = .80, .62, and .70, respectively). Of group B with failed forearm loop arteriovenous graft, 36% became candidates for upper arm arteriovenous fistula with dilation of ipsilateral upper arm cephalic or basilic vein to ⩾3 mm.

CONCLUSION

In this study, forearm loop arteriovenous graft with adequate upper arm vein did not show a statistical difference in mid-term patencies compared with upper arm arteriovenous fistula. For those forearm loop arteriovenous grafts with inadequate upper arm vein, approximately one-third of patients became candidates for upper arm arteriovenous fistula demonstrating the benefits forearm loop arteriovenous graft.

Options for end stage vascular access: Translumbar catheter, arterial-arterial access or right atrial graft?

Background:

Running out of vascular access for dialysis is thankfully rare, but despite this, most units will have a number of patients with few options and in a precarious state. The increasing longevity of dialysis patients portends more patients will reach minimal access options. End stage vascular access is poorly defined but classification may enable assessment and comparison of treatment options. Three options for patients with end stage access are a central venous catheter through a translumbar or transhepatic route, arterial-arterial prosthetic loop or a right atrial graft.

Aims:

The aims of this study are to provide a structured review of evidence for these procedures to allow application and guide practice for patients with end stage vascular access.

Methods:

A standardised search of published literature was performed of relevant studies. In addition, the references cited in those papers were assessed for any further available articles. All study types were included and reviewed by two authors independently. Primary outcomes were patient survival and secondary patency rate at 3 and 12 months. Secondary outcomes were long-term patency rates, mean time to cannulation and complications such as access dysfunction, thrombosis and infection.

Summary:

Based on the available evidence, it would appear that arterial-arterial prosthetic loop is a definitive option for maintaining dialysis access in patients with no more arteriovenous access options. Translumbar and transhepatic dialysis catheters may offer short- and medium-term options and right atrial grafts may also be suitable as an option where arterial-arterial prosthetic loop is unsuitable.

Interwoven Nitinol Stents to Treat Radiocephalic Anastomotic Arteriovenous Fistula Stenosis

Purpose: To determine the clinical outcomes in hemodialysis patients after implantation of a Supera stent to treat juxta-anastomotic stenosis in radiocephalic arteriovenous fistulas (AVF). Materials and Methods: A single-center retrospective study was conducted of 42 consecutive patients (mean age 66.7 years, range 40–84; 26 men) who had a failing AVF due to juxta-anastomotic stenosis treated with the interwoven Supera stent between February 2014 and February 2018. A third of the patients had previous juxta-anastomotic intervention (either balloon angioplasty or open surgical revision). Results: The stent was inserted successfully in all patients. Overall mean follow-up was 12.2±8.2 months (range 3.8–38.3). Juxta-anastomotic segment primary patency estimates at 6 and 12 months were 92.5% and 59.8%, respectively, with assisted primary patency rates of 97.5% and 92.9%. Reintervention (elective drug-coated balloon angioplasty) occurred at a rate of 0.31 procedures/year. Two AVFs thrombosed during the 1-year follow-up and were revascularized using balloon angioplasty. Ultrasound measurements of brachial artery flow rates increased significantly from 543.5±96.72 mL/min (range 430–644) before intervention to 919.2±355.9 mL/min (range 200–1600) after intervention (p=0.047). Arterial pressures on hemodialysis improved from −142.3±24.9 mm Hg (range −100 to −180) to −123.4±21.9 mm Hg (range −100 to −184; p=0.051). No AVFs were lost or abandoned during the follow-up period. Conclusion: The interwoven Supera stent is a promising treatment for failing AVFs with juxta-anastomotic stenosis. Encouraging 1-year primary and assisted primary patency was demonstrated, with a low reintervention rate. This treatment facilitates long-term maintenance of AVF vascular accesses.

Routine use of ultrasound to avert mechanical complications during placement of tunneled dialysis catheters for hemodialysis

OBJECTIVE

While placement of tunneled dialysis catheters for hemodialysis access is considered a routine procedure, it is associated with a small chance of mechanical complications. Because the literature examining these issues is not recent and our impression of the incidence of these postprocedural complications is at variance with the existing literature, we decided to review our experience.

METHODS

Since 1998, our vascular service has placed 1766 tunneled hemodialysis catheters in 1065 patients for hemodialysis access. All catheters were placed with ultrasound guidance for the puncture, with selective use of a micropuncture set for patients with low-volume status. All patients underwent chest radiography at the end of each procedure.

RESULTS

The average age of the patients was 61 ± 21 (standard deviation) years. Among the 1065 patients, 44% were female; 93% of catheters were placed in the right internal jugular vein and 7% in the left internal jugular vein. The prevalence of diabetes and hypertension in our population of patients was 52% and 72%, respectively. In this consecutive series, no case of postprocedure hemothorax or pneumothorax was encountered. Two cutdowns had to be performed because of injury to branches of the external carotid artery. Three patients had to have a subsequent revision because of malpositioning of the catheter.

CONCLUSIONS

Using modern-day techniques, the incidence of mechanical complications during placement of tunneled catheters can be diminished. Hence, routine use of ultrasound guidance for insertion of tunneled dialysis catheters should become the standard of care.

Baseline characteristics of arm vessels by preoperative duplex ultrasonography in Korean patients for hemodialysis vascular access

BACKGROUND

Preoperative mapping with duplex ultrasonography is crucial for successful vascular access creation for hemodialysis. The aims of this study are to assess the baseline characteristics of arm vessels by preoperative duplex ultrasonography in Korean patients, to find out a preoperative duplex ultrasonography parameter precluding distal arteriovenous fistula creation, to assess the maturation failure rate of arteriovenous fistulas, and to identify associated risk factors.

METHODS

Preoperative duplex ultrasonography mapping for vascular access creation was done in all patients with end-stage renal diseases during the year 2015. The baseline data of duplex ultrasonography were retrospectively analyzed with follow-up clinical data.

RESULTS

A total of 299 end-stage renal disease patients (mean age = 62 years, 62% male) were included. On preoperative duplex ultrasonography, mean diameters of radial artery and cephalic vein at wrist were 2.03 and 2.40 mm in the non-dominant arm and 2.10 and 2.26 mm in the dominant arm, respectively. The most common reason for precluding radial-cephalic arteriovenous fistula at wrist was small-sized cephalic vein. Multivariate logistic regression analysis revealed that the risk factors for inadequate vessels were warfarin treatment, old age (⩾75 years), and peripheral arterial occlusive disease. The rate of arteriovenous fistula maturation failure was 21% and vein diameter <2.5 mm was the only risk factor for arteriovenous fistula maturation failure by multivariate logistic regression analysis.

CONCLUSION

Preoperative duplex ultrasonography evaluation is important to find out inadequate vessels for native arteriovenous fistula and to determine the location of vascular access.

DermaPort: A Novel Ported Vascular Access System for Hemodialysis

Safe, ported access to the body for hemodialysis and other medical uses is increasingly necessary for modern medical therapy. Long-term hemodialysis offers unique challenges with its requirements for high blood flow, chronic implantation, and risks of infection. Although widely used, the polyester, cuffed, delete word and space hemodialysis catheter is far from ideal, and there is a need for an improved vascular access system to allow catheter adjustment and replacement, to reduce infections and to reduce medical costs. The DermaPort ported vascular access system (PVAS) was developed to meet this need. This report describes the design and testing of the PVAS port in vitro and in vivo. The results demonstrate that the system provides superior tissue integration coupled with infection-resisting slidability, allowing reposition and exchange of an indwelling catheter. Within 3 weeks, there was strong tissue ingrowth and establishment of a sterile barrier and over 13 weeks there was no evidence of infection or marsupialization. Additionally, an explanted PVAS sample from a 38 patient human clinical study showed the bulk of the metal mesh was associated with a macrophage-giant cell response and contained collagen and vascular elements. From these data, we conclude that the PVAS permitted stable ported access following a single stage implant procedure.

Improving precision in prediction: Using kidney failure risk equations as a potential adjunct to vascular access planning

The timing of referral for creation of vascular access in a patient with declining kidney function is difficult to predict. Current methods may result in patients undergoing unnecessary procedures and subsequent interventions on accesses that are never used. Multiple variables, including time for assessment, surgery and follow-up that considers the likelihood of access failure, and the estimated rate of kidney function decline, make vascular access planning challenging and difficult to balance. Better prediction tools that incorporate the risks of progressive decline in kidney function with the risk of access failure and the competing risk of death would facilitate decision-making in vascular access. The kidney failure risk equation is a validated, simple online tool that estimates the probability of the 2- and 5-year risk of reaching end-stage kidney disease. While the use of the kidney failure risk equation has not been validated as an adjunct to planning vascular access, it has potential and may facilitate more individualised care and more appropriate allocation of resources.

Placement issues of hemodialysis catheters with pre-existing central lines and catheters

OBJECTIVE

It has been a widely accepted practice that a previous placed pacemaker, automatic implantable cardioverter defibrillators, or central line can be a contraindication to placing a hemodialysis catheter in the ipsilateral jugular vein. Fear of dislodging pacing wires, tunneling close to the battery site or causing venous obstruction has been a concern for surgeons and interventionalists alike. We suggest that this phobia may be unfounded.

METHODS

A retrospective review was conducted of patients in whom hemodialysis catheters were placed over a period of 10 years. For each hemodialysis catheter that was placed, perioperative chest X-ray performed was used to evaluate for pre-existing pacemakers and central lines. The position and laterality of placement of the hemodialysis catheter along with presence of arteriovenous fistula with functional capacity for access were noted.

RESULTS

A total of 600 hemodialysis catheters were placed in patients over the period of 10 years. The mean age of the patients was 73.6 ± 12 years with a median age of 76 years. We found 20 pacemakers or automatic implantable cardioverter defibrillators and 19 central lines on the same side of the neck as the hemodialysis catheter that was placed in the ipsilateral jugular vein. No patient exhibited malfunction or dislodgment of the central line, the pacemaker, or automatic implantable cardioverter defibrillator or evidence of upper extremity venous obstruction based upon signs symptoms or duplex exams.

CONCLUSION

Based on our experience, we suggest that placement of hemodialysis catheter in the internal jugular vein ipsilateral to the pre-existing catheter/leads is safe and spares the contralateral limb for arteriovenous fistula creation.

Controversies in the management of the haemodialysis-related arteriovenous fistula following kidney transplantation

Arteriovenous fistula (AVF) is regarded as the best vascular access for chronic haemodialysis (HD). Still, AVF inherently causes significant haemodynamic changes. Although the necessity for vascular access despite its putative cardiovascular complications favours AVF creation in patients under chronic HD, one may question whether sustaining a functional AVF after successful kidney transplantation extends the haemodynamic threat. Small prospective series suggest that AVF ligation causes rapid and sustained reduction in left ventricular hypertrophy. Still, the benefits of such a cardiac remodelling in long-terms of cardiovascular morbi-mortality still need to be proven. Furthermore, the elevation of diastolic blood pressure and arterial stiffness caused by AVF ligation may blunt the expected cardio-protection. Finally, the closure of a functioning AVF may accelerate the decline of kidney graft function. As a whole, the current management of a functioning AVF in kidney transplant recipients remains controversial and does not rely on strong evidence-based data. The individual risk of graft dysfunction and a return to chronic HD also needs to be balanced. Careful pre-operative functional assessments, including cardio-pulmonary testing and estimated glomerular filtration rate slope estimation, may help better selection of who might benefit the most from AVF closure. Large-scale prospective, ideally multi-centric, trials are essentially needed.