REDUCING TUNNELED HEMODIALYSIS CATHETER MORBIDITY: Hemodialysis Catheter-Associated Central Venous Stenosis

Dialysis nurses' knowledge, attitude, practice and self-efficacy regarding vascular access: A cross-sectional study in Singapore

INTRODUCTION

Dialysis nurses play a paramount role in vascular access (VA) management. The aim of this study is to evaluate dialysis nurses' knowledge, attitude, practice and self-efficacy (KACP-SE) pertaining to VA cannulation and evaluation.

METHOD

An anonymous self-administered survey was administered to dialysis nurses from two tertiary hospitals (four dialysis units) and two community dialysis centres from April to May 2022. The 37-items survey consists of four dimensions of questions relating to VA cannulation and management: knowledge, attitude, practice and self-efficacy. The content validity and face validity of the survey was reviewed by three experienced VA professionals and five dialysis nurses respectively. The internal consistency and construct validity of the survey have been assessed with psychometric tests.

RESULTS

There were 23 and 47 nurses, working in the participated community and tertiary hospital dialysis centres respectively, responded to the survey. The internal consistency coefficients indicated acceptable reliability of the instrument (KR-20 coefficient was 0.55 and 0.76 for knowledge and practice domains; Cronbach's α was 0.85 and 0.64 for self-efficacy and attitude domains). In the exploratory factor analysis for attitude and self-efficacy, the instrument could account for 64.0% and 53.0% of the total variance respectively. In the knowledge domain, five out of eight single-select multiple-choice questions were correctly answered by >70% of the participants. Overall, the mean (±SD) of participants' total self-efficacy score was 24.3 (±3.1) over total score of 30. The majority of the participants (82.4%) either agreed or strongly agreed that ultrasound guidance is useful for cannulation.

CONCLUSION

This KAP-SE instrument can be used to evaluate knowledge, attitude, practice and self-efficacy of dialysis nurses toward VA management. The participants demonstrated acceptable knowledge level, but with some knowledge gaps identified. It also revealed nurses' good self-efficacy level and welcoming attitude towards adopting ultrasound in VA cannulation among the participants.

CT guided sharp recanalization to restore dialysis access in patients with central venous obstruction: A single centre experience and review of alternative techniques

Central venous obstructions that impedes catheter placement or results in catheter dysfunction is a significant problem for haemodialysis patients. Recanalization can be performed with an intent to restore central venous access, improve outflow from arteriovenous fistula or to relieve symptomatic venous obstructions. Sharp recanalization encompasses various interventional techniques using a sharp instrument to puncture through or bypass around a venous obstruction. In this paper we outline our experience performing CT guided sharp recanalization and review alternative sharp recanalization techniques that are specifically used to restore haemodialysis access in patients with thoracic central venous obstruction.

Hemodialysis nurses' knowledge, attitude, and practices in managing vascular access: A cross-sectional study in Saudi Arabia

Hemodialysis continues to be the primary approach for renal replacement therapy. Vascular access (VA), particularly arteriovenous fistula or arteriovenous graft, is the preferred technique for establishing hemodialysis access due to its lower risk of infection and central venous stenosis compared to catheters. The aim of this cross-sectional investigation was to examine hemodialysis nurses' knowledge, confidence, and practices in managing VA in Saudi Arabia. This is an online cross-sectional survey study that was conducted in Saudi Arabia between June and August 2023. This study utilized a previously validated questionnaire. Examined dialysis nurses' knowledge, attitude, practice, and self-efficacy pertaining to VA cannulation and evaluation. Binary logistic regression analysis was used to identify predictors of better knowledge of dialysis VA. A total of 197 participants were involved in this study. Around one-third of the study participants (37.0%) reported that they have received specialized training in managing VA. Participants agreement (answered agree or strongly agree) on statements that examined attitudes toward dialysis VA cannulation and management was high and ranged between 75.0% and 93.0%. The majority of participants (97.5%) reported that they perform this assessment. Most nurses (65%) preferred the rope-ladder technique. Participants agreement on statements that examined self-efficacy on dialysis VA cannulation and management was high and ranged between 72.1% and 98.0%. The most commonly agreed upon statement was that "they have confident in performing hemodialysis access (arteriovenous fistula and arteriovenous graft) assessment before cannulation." With 98.0% (answered agree and strongly agree). The mean knowledge score for our study sample was 6.4 (SD: 2.0) out of 12 (53.3%); which reflects marginal-level of knowledge on dialysis VA. Binary logistic regression analysis identified that nurses who have undergraduate degree are 92% more likely to be knowledgeable on dialysis VA compared to others (P < .05). Concerning VA, the level of knowledge among hemodialysis nurses working in Saudi Arabia was inadequate. Nurses who hold an undergraduate degree are presumed to have a more extensive understanding of dialysis VA. Further education programs are necessary for HD nurses to enhance their knowledge of VA, thereby optimizing their professional practices and enhancing the outcomes for their patients.

Friction injury of the central vein caused by catheter for hemodialysis: an in vitro study

Vascular injury such as central venous stenosis (CVS) is a common complication in hemodialysis patients with central venous catheters (CVCs), yet the impact of the microstructure and partial physic characteristics of catheter surface on the chronic injury of central vein has not been elucidated. In this study, the microscopic morphology of tips and bodies of six different brands of polyurethane CVCs was observed and their roughness was assessed. Subsequently, an in vitro model was established to measure the coefficients of friction (COF) between CVCs (tips and bodies) and the vena cava intima of Japanese rabbits under the same condition in a linear reciprocating mode, and changes in the intima of vessels after friction were observed. The study found that there was a significant variation in surface roughness among different brands of CVCs (tips P < 0.001, bodies P = 0.02), and the COF was positively correlated with the catheter surface roughness (tips P = 0.005, R = 0.945, bodies P = 0.01, R = 0.909). Besides, the endovascular roughness increased after friction. These findings suggest that the high roughness surface of CVCs may cause chronic mechanical friction injury to the central venous intima, which is one of the potential factors leading to CVS or occlusion. This provides a breakthrough for reducing complications, improving patient prognosis, and advancing catheter surface lubrication technology.

Management of thoracic outlet syndrome in patients with hemodialysis access

Patients with threatened arteriovenous access are often found to have central venous stenoses at the ipsilateral costoclavicular junction, which may be resistant to endovascular intervention. Stenoses in this location may not resolve unless surgical decompression of thoracic outlet is performed to relieve the extrinsic compression on the subclavian vein. The authors reviewed the management of dialysis patients with central venous lesions at the thoracic outlet, as well as the role of surgical decompression with first-rib resection or claviculectomy for salvage of threatened, ipsilateral dialysis access.

Guidelines on vascular access for hemodialysis from the Brazilian Society of Angiology and Vascular Surgery

Chronic kidney disease is a worldwide public health problem, and end-stage renal disease requires dialysis. Most patients requiring renal replacement therapy have to undergo hemodialysis. Therefore, vascular access is extremely important for the dialysis population, directly affecting the quality of life and the morbidity and mortality of this patient population. Since making, managing and salvaging of vascular accesses falls within the purview of the vascular surgeon, developing guideline to help specialists better manage vascular accesses for hemodialysis if of great importance. Thus, the objective of this guideline is to present a set of recommendations to guide decisions involved in the referral, evaluation, choice, surveillance and management of complications of vascular accesses for hemodialysis.

Management of Central Venous Stenoses and Occlusions

Symptomatic central venous stenosis and occlusion remains the gordian knot of vascular access. Advances in techniques, like sharp recanalization, allowed for improved success rates in crossing these difficult lesions. There is also increasing evidence of new devices in treating central venous stenosis and, at the same time, improving the time needed between interventions. High-pressure balloons, paclitaxel-coated balloons, bare metal stents and covered stents have been tested with an aim to offer additional treatment options, although obstacles still exist. In the current review, authors describe relevant techniques and options, provide the evidence and evaluate the actual implementation of these devices in this demanding field.

Stenting of innominate vein compression syndrome

We report the case of a 60-year-old woman who sought medical attention for left cervical and supraclavicular pain and swelling. Previous computed tomography, intravascular ultrasound, and venography studies were reviewed, confirming extrinsic compression of the left innominate vein by the left common carotid artery against the left clavicle head. Stenting of the lesion was performed, with good mid-term symptom relief and patency. It is, to the best of our knowledge, the first case study in the literature to report endovascular treatment of this syndrome.

Central venous stenosis after subclavian versus internal jugular dialysis catheter insertion (CITES) in adults in need of a temporary central dialysis catheter: study protocol for a two-arm, parallel-group, non-inferiority randomised controlled trial

BACKGROUND

The right internal jugular vein is currently recommended for temporary central dialysis catheters (tCDC) based on results from previous studies showing a lower incidence of central vein stenosis compared to the subclavian vein. Data is however conflicting, and there are several advantages when the subclavian route is used for tCDCs. This prospective, controlled, randomised, non-inferiority study aims to compare the incidence of post-catheterisation central vein stenosis between the right subclavian and the right internal jugular routes.

METHODS

Adult patients needing a tCDC will be included from several hospitals and randomised to either subclavian or internal jugular vein catheterisation with a silicone tCDC. Inclusion continues until 50 patients in each group have undergone a follow-up CT venography. The primary outcome is the incidence of post-catheterisation central vein stenosis detected by a CT venography performed 1.5 to 3 months after removal of the tCDC. Secondary outcomes include between-group comparisons of (I) the patients' experience of discomfort and pain, (II) any dysfunction of the tCDC during use, (III) catheterisation success rate and (IV) the number of mechanical complications. Furthermore, the ability to detect central vein stenosis by a focused ultrasound examination will be evaluated using the CT venography as golden standard.

DISCUSSION

The use of the subclavian route for tCDC placement has largely been abandoned due to older studies with various methodological issues. However, the subclavian route offers several advantages for the patient. This trial is designed to provide robust data on the incidence of central vein stenosis after silicone tCDC insertion in the era of ultrasound-guided catheterisations.

TRIAL REGISTRATION

Clinicaltrials.gov; NCT04871568. Prospectively registered on May 4, 2021.

Direct Connection to the ECMO Circuit versus a Hemodialysis Catheter Is Associated with Improved Urea Nitrogen Ultrafiltration during Continuous Renal Replacement Therapy for Patients on Extracorporeal Membrane Oxygenation

For patients on extracorporeal membrane oxygenation (ECMO) who require renal replacement therapy (RRT), dialysis can be achieved through a dedicated hemodialysis (HD) catheter or direct connection to the ECMO circuit. The relative effect of each on filtration efficacy is not known. We conducted a retrospective single-center analysis of patients on ECMO who required CRRT. We examined the outcomes of blood biomarkers and transmembrane filter pressures, comparing sessions by attachment approach. All analyses were clustered by patient. Of the 33 patients (7 ECMO access and 23 HD catheter access) that met the inclusion criteria, there were a total of 493 CRRT sessions (93 ECMO access and 400 HD catheter access). At the end of the first 12 h of CRRT therapy, the ECMO group had a greater rate of decline in serum BUN than the HD catheter access group (2.5 mg/dl (SD 11) vs. 2 mg/dl (SD 6), p = 0.035). Additionally, the platelet level was significantly higher in the ECMO group compared to the HD catheter access group after 72 h (94.5 k/uL (SD 41) vs. 71 k/uL (SD 29), p = 0.008). Utilizing the ECMO circuit as direct venous access for CRRT was associated with some improved filtration proximal outcomes.

Hemodialysis Catheters: Update on Types, Outcomes, Designs and Complications

Hemodialysis catheters (HDCs) are an essential part of kidney replacement therapy. While these catheters are considered only the bridge to long-term vascular access such as arteriovenous fistulas and grafts, they are associated with significant morbidity and mortality and subsequent increased health care expenditures. However, despite these risks, a large proportion of end stage kidney disease population initiates dialysis using these catheters. The pathogenicity of HDCs stems from its invasive nature to the venous vasculature tree resulting in both mechanical and infectious complications. Therefore, the wide use these catheters in dialysis population and the associated complications necessitated continuous innovations in the catheter material, design, and placement techniques. This review provides an update on the catheter types, catheter tip designs, and the new technologies and innovations aimed to improve the catheter functionality and mitigate its related complications.

Comparison of Management for Central Venous Stenosis With or Without Previous Catheter Placement

Objective: To compare central venous stenosis/occlusion with or without previous jugular catheter placement history.

Methods: Data of patients with central vein stenosis/occlusion receiving endovascular intervention in our hospital from January 2015 to December 2018 were collected and analyzed.

Results: Twenty-nine patients with previous jugular catheter placement history (CVC group) and 33 patients (excluded two with technical failure) without such history (non-CVC group) are included in this study. Previous jugular catheter placement history raised the risk of postintervention recurrence 1.02 times (CVC group vs. non-CVC group, HR = 2.02 95%CI: 0.91–4.48). The primary patency rate at 6, 12, 18, and 24 months was 76.9, 54.2, 45.5, and 25.0% separately in the CVC group and 80.6, 70.0, 67.9, and 44.4% separately in the non-CVC group. The assisted primary patency rate at 6, 12, 18, and 24 months was 92.3, 91.7, 86.4, and 68.8% separately in the CVC group and 93.5, 90.0, 82.1, and 61.1% separately in the non-CVC group. Patients in the CVC group received a higher frequency of reintervention (0.7 times/year/patient vs. 0.3 times/year/patient). There was no significant difference in the assisted primary patency rate between the two groups. Different primary interventions (angioplasty alone, bare metal stent, stent graft) did not affect primary patency and assisted primary patency, but percutaneous transluminal stenting (PTS) with a bare metal stent had a significant lower primary patency rate between 3 and 24 months compared with PTS with a stent graft (p = 0.011).

Conclusion: Central venous stenosis/occlusion with a previous jugular catheter placement history develops symptoms earlier and had a worse prognosis after endovascular intervention. More efforts are needed to carry out end-stage kidney disease life plan to reduce the harm of evitable catheter placement.

Unilateral jugular vein stenosis in five horses and experience with percutaneous transluminal angioplasty

BACKGROUND

Venous stenosis, a possible cause of jugular dilatation and congestion, is well known in human medicine but has poorly been described in horses.

OBJECTIVE

To report unilateral jugular vein stenosis as a cause of jugular vein dilatation in horses and describe treatment by percutaneous transluminal angioplasty (PTA).

STUDY DESIGN

Case report.

METHODS

Details of horses diagnosed with unilateral jugular stenosis were retrieved from medical records.

RESULTS

Five horses were presented with a non-painful, unilateral dilatation of the jugular vein of which two horses showed headshaking during exercise. In one horse an indwelling catheter had been used and jugular dilatation developed 4 weeks later. In the other horses, no intravenous injections had been administered in the months before jugular dilatation developed. Ultrasonographic examination revealed venous stenosis in all horses approximately 5-10 cm cranial to the thoracic inlet. The internal diameter at the level of this stenosis was only 1-3.1 mm. The length of the stenosis was about 15-19 mm with a markedly thickened intima and media on ultrasonography. After enoxaparin treatment, PTA was performed in three horses. During the procedure the stenotic vein was dilated three times with progressively increasing pressures up to 12 atm. The stenotic diameter increased to a maximum of 4.9 mm with improved jugular blood flow. Aftercare included anti-inflammatory and anti-thrombotic therapy.

CONCLUSION

Jugular vein stenosis occurs in horses and should be included in the differential diagnoses of unilateral jugular vein dilatation. It may present in the absence of previous intravenous treatment. PTA of the jugular vein is feasible to improve jugular blood flow.

Lesion Type Analysis of Hemodialysis Patients Who Underwent Endovascular Management for Symptomatic Central Venous Disease

Purpose

Central venous lesions (CVLs) can adversely affect hemodialysis access maturation and maintenance, which in turn worsen patient morbidity and access circuit patency. In this study, we assessed several clinical variables, patient characteristics, and clinical consequences of symptomatic central vein stenosis and obstruction in patients who underwent renal replacement therapy in the form of hemodialysis.

Patients and Methods

The medical records of all hemodialysis patients with clinically symptomatic CVLs who underwent digital subtraction angiography treatment at King Abdullah University Hospital between January 2017 and December 2019 were retrieved. Patient characteristics and the clinical and anatomical features of CVLs were analyzed retrospectively. Pearson’s chi-square tests of association were used to identify and assess relationships between patient characteristics and CVLs.

Results

The study cohort comprised 66 patients with end-stage renal disease who developed symptomatic central vein stenosis. Of the 66 patients, 56.1% were men, and their mean age was approximately 52 years. Most (62.1%) of the patients were determined to have a history of central catheter insertion into the jugular vein. Hypertension was the most common comorbidity (78.8%, p<0.001), followed by type 2 diabetes mellitus (47.0 %, p<0.01). The incidence of stenosis was found to be significantly higher in the brachiocephalic vein than in other central veins (43.9%, p<0.001). A repeated central catheter insertion in a patient was predictive of central venous occlusion (p<0.05). Stenotic lesions were found to be associated with a significantly higher success rate than occlusive lesions (91.2%, p<0.01).

Conclusion

Multiple central venous catheters (CVCs) are found to be associated with occlusive CVLs and unfavorable recanalization outcomes. Multiple CVC should be avoided by creating a permanent vascular access in a timely fashion for patients with chronic kidney disease and by avoiding the ipsilateral insertion of CVC and AVF.

Clinical relevance of the left brachiocephalic vein anatomy for vascular access in dialysis patients

INTRODUCTION

Most hemodialysis patients start renal replacement therapy with a central venous catheter (CVC). The left internal jugular vein (LIJV) is the second-choice vein for CVC positioning, after the right IJV. However, to reach the right atrium, the CVC must pass through the left brachiocephalic vein (LBV), which also drains blood from the left arm through the subclavian vein. The purpose of this study is to describe how the anatomy of the central venous system and in particular that of the LBV affects vascular access in hemodialysis patients.

MATERIALS AND METHODS

Three-dimensional (3D) virtual model reconstructions of the central thoracic veins of three hemodialysis patients were obtained from contrast-enhanced computed tomography scans acquired in the venous phase. The images were exported as DICOM files and loaded on open-source software for visualizing and analyzing the medical imaging (3D Slicer, Windows version 4.8.1).

RESULTS

As expected, the 3D reconstructions showed that the LBV has a tortuous path with three main angulations that could be associated with external compression and stenosis. These could determine the difficulties and increased risks of venous injury during CVC placement, and an increased risk of medium to long-term catheter-associated vein thrombosis and stenosis.

CONCLUSIONS

The anatomical features of the LBV indicate that the path of a CVC from the LIJV to the right atrium is tortuous and can easily be complicated by vein injury, negatively affecting the creation of future arterio-venous vascular accesses in the left arm.

High resolution, 3-dimensional Ferumoxytol-enhanced cardiovascular magnetic resonance venography in central venous occlusion

BACKGROUND

Although cardiovascular magnetic resonance venography (CMRV) is generally regarded as the technique of choice for imaging the central veins, conventional CMRV is not ideal. Gadolinium-based contrast agents (GBCA) are less suited to steady state venous imaging than to first pass arterial imaging and they may be contraindicated in patients with renal impairment where evaluation of venous anatomy is frequently required. We aim to evaluate the diagnostic performance of 3-dimensional (3D) ferumoxytol-enhanced CMRV (FE-CMRV) for suspected central venous occlusion in patients with renal failure and to assess its clinical impact on patient management.

METHODS

In this IRB-approved and HIPAA-compliant study, 52 consecutive adult patients (47 years, IQR 32-61; 29 male) with renal impairment and suspected venous occlusion underwent FE-CMRV, following infusion of ferumoxytol. Breath-held, high resolution, 3D steady state FE-CMRV was performed through the chest, abdomen and pelvis. Two blinded reviewers independently scored twenty-one named venous segments for quality and patency. Correlative catheter venography in 14 patients was used as the reference standard for diagnostic accuracy. Retrospective chart review was conducted to determine clinical impact of FE-CMRV. Interobserver agreement was determined using Gwet's AC1 statistic.

RESULTS

All patients underwent technically successful FE-CMRV without any adverse events. 99.5% (1033/1038) of venous segments were of diagnostic quality (score ≥ 2/4) with very good interobserver agreement (AC1 = 0.91). Interobserver agreement for venous occlusion was also very good (AC1 = 0.93). The overall accuracy of FE-CMRV compared to catheter venography was perfect (100.0%). No additional imaging was required prior to a clinical management decision in any of the 52 patients. Twenty-four successful and uncomplicated venous interventions were carried out following pre-procedural vascular mapping with FE-CMRV.

CONCLUSIONS

3D FE-CMRV is a practical, accurate and robust technique for high-resolution mapping of central thoracic, abdominal and pelvic veins and can be used to inform image-guided therapy. It may play a pivotal role in the care of patients in whom conventional contrast agents may be contraindicated or ineffective.

Quality of Life of Patients Using the Hemodialysis Reliable Outflow (HeRO) Graft in Hemodialysis

End-stage renal disease (ESRD) is one of the most feared consequences of kidney disease. A large number of patients with ESRD require long-term hemodialysis. Vascular access options for hemodialysis include the placement of arteriovenous (AV) fistulas, AV grafts, and tunneled dialysis catheters (TDCs). An alternative to the TDC is the Hemodialysis Reliable Outflow (HeRO; Cryolife Inc., Eden Prairie, MN, USA) Graft. The HeRO Graft has been designed to overcome the development of central venous stenosis or occlusion. The objective is to evaluate the quality of life of patients using the HeRO Graft in end-stage renal disease for hemodialysis. We searched PubMed, Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica dataBASE (EMBASE), Cumulative Index to Nursing and Allied Health Literature (CINHAL), Directory of Open Access Journals (DOAJ), Pubpsych, and Google Scholar on October 30, 2018. We included published articles in the English language that used the HeRO Graft for ESRD. The adequacy of dialysis and bacteremia rates proved to be equal to those of conventional AV grafts. It turned out that 2.21 interventions per year were needed to maintain the patency of the HeRO Graft while only 1.17 interventions were needed to maintain the patency of the lower extremity graft. Mortality, ischemia, and infection rates were similar for both groups. The tunneled dialysis catheters have a higher incidence of infection as compared to the HeRO Graft. The initial device and placement costs for the HeRO Graft were higher than those for TDCs but savings from the lower incidence of device complications and longer effective device patency make it cost-effective. Based on the limited evidence, it has been discerned that the HeRO Graft is an optimal option for hemodialysis in patients of ESRD who have exhausted all means of upper extremity access. Though almost similar to the AV grafts in terms of complications and less functional than femoral grafts, it still outclasses them in improving the quality of life of such patients.

Clinical and Regulatory Considerations for Central Venous Catheters for Hemodialysis

Central venous catheters remain a vital option for access for patients receiving maintenance hemodialysis. There are many important and evolving clinical and regulatory considerations for all stakeholders for these devices. Innovation and transparent and comprehensive regulatory review of these devices is essential to stimulate innovation to help promote better outcomes for patients receiving maintenance hemodialysis. A workgroup that included representatives from academia, industry, and the US Food and Drug Administration was convened to identify the major design considerations and clinical and regulatory challenges of central venous catheters for hemodialysis. Our intent is to foster improved understanding of these devices and provide the foundation for strategies to foster innovation of these devices.

Studying alternative approaches for placement of cuffed hemodialysis catheters in hemodialysis patients with bilateral internal jugular vein occlusion

Introduction:

Internal jugular vein occlusion often makes necessary the use of less desirable routes as external jugular, subclavian, and femoral vein approaches in addition to inferior vena cava approaches. This a prospective cross-sectional follow-up study of the alternative approaches for placement of cuffed hemodialysis catheters in end-stage renal disease patients with bilateral internal jugular vein occlusion from the interventional nephrology point of view.

Method:

The study was conducted on 134 end-stage renal disease patients who were referred for insertion of a challenging hemodialysis catheter due to bilateral internal jugular vein occlusion. Ultrasound Doppler guided catheter insertion was used as a routine practice in addition to fluoroscopy or post insertion X-ray to localize catheter tip position and exclude complications. Follow-up of patients was conducted until the end of the study or catheter removal.

Findings:

The most highly prevalent alternative approach is the trans-external iliac vein inferior vena cava approach (43.28%) followed by external jugular vein approach (14.93%), innominate vein approach (10.18%), internal jugular vein collaterals by interventional radiology (7.46%), femoral vein approach (7.46%), transhepatic approach (5.97%), subclavian vein approach (5.22%), and finally the retrograde femoral vein approach (1.49%).

Discussion:

End-stage renal disease patients maintained on regular hemodialysis who have bilateral internal jugular vein obstruction and non-functioning arteriovenous fistula/graft is a daily scenario in nephrology practice. Our study showed that there is a variety of approaches for the insertion of cuffed hemodialysis catheters other than occluded internal jugular veins. Interventional nephrologists have a major role in solving the problem of poor hemodialysis vascular access. These alternative approaches can conserve the anatomically limited number of percutaneous access sites in each patient.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

Clinical outcomes of totally implantable venous access port placement via the axillary vein in patients with head and neck malignancy

PURPOSE:

To evaluate the clinical outcomes and complications of totally implantable venous access port implantation via the axillary vein in patients with head and neck malignancy.

MATERIALS AND METHODS:

A total of 176 totally implantable venous access ports were placed via the axillary vein in 171 patients with head and neck malignancy between May 2012 and June 2015. The patients included 133 men and 38 women, and the mean age was 58.8 years (range: 19-84 years). Medical records were retrospectively reviewed.

RESULTS:

This study included a total of 93,237 totally implantable venous access port catheter-days (median 478 catheter-days, range: 13-1380 catheter-days). Of the 176 implanted totally implantable venous access port, complications developed in nine cases (5.1%), with the overall incidence of 0.097 events/1000 catheter-days. The complications were three central line-associated blood-stream infection cases, one case of keloid scar at the needling access site, and five cases of central vein stenosis or thrombosis on neck computed tomography images. The 133 cases for which neck computed tomography images were available had a total of 59,777 totally implantable venous access port catheter-days (median 399 catheter-days, range: 38-1207 catheter-days). On neck computed tomography evaluation, the incidence of central vein stenosis or thrombosis was 0.083 events/1000 catheter-days. Thrombosis developed in four cases, yielding an incidence of 0.067 events/1000 catheter-days. All four patients presented with thrombus in the axillary or subclavian vein. Stenosis occurred in one case yielding an incidence of 0.017 events/1000 catheter-days. One case was catheter-related brachiocephalic vein stenosis, and the other case was subclavian vein stenosis due to extrinsic compression by tumor progression. Of the nine complication cases, six underwent port removal.

CONCLUSION:

These data indicate that totally implantable venous access port implantation via the axillary vein in patients with head and neck malignancy is safe and feasible, with a low axillary vein access-related complication rate.

One-stage operation for superficialization of native radio-cephalic fistula in obese patients

Purpose:

The population of obese patients is increasing in general and also at hemodialysis initiation. For successful cannulation of arteriovenous fistula, the National Kidney Foundation-Dialysis Outcome Quality Initiative guidelines suggest that the required maturation parameters are at a depth of <6 mm. There are several reports describing two-stage superficialization of arteriovenous fistulas in obese cases. Therefore, we investigated the utility and complications of one-stage superficialization of radio-cephalic fistula.

Methods:

From January 2011 to March 2017, we simultaneously performed forearm radio-cephalic fistula creation and superficialization of the cephalic vein for 10 patients having obesity (body mass index > 30 kg/m2) and deep cephalic vein (>6 mm). Initially, an arteriovenous anastomosis was created at an appropriate site. Subsequently, an 8–10 cm longitudinal skin incision was made along the lateral aspect of the forearm cephalic vein. The cephalic vein was identified and exposed. The cephalic vein was repositioned superficially.

Results:

The mean age of the patients was 53 years (range: 40–72 years) and the mean body mass index was 40.2 kg/m2 (33.1–59.7 kg/m2). The cause of renal failure in eight patients was diabetic nephropathy, and in two patients, it was unknown. After the procedure, vein depth became 3.4 mm (1.9–4.6 mm) from 8.2 mm (6.0–13.4 mm). All patients who initiated dialysis underwent successful two-needle cannulation. Primary patency rate was 71.4% at 12 months (two patients underwent percutaneous transluminal angioplasty) and secondary patency rate was 100%. There was one procedure-related complication and delayed wound healing, which was improved by observation without antibiotics.

Conclusion:

This small series of patients indicates that one-stage superficialization of radio-cephalic fistula is a safe and effective option to start hemodialysis in obese subjects.

Left Brachiocephalic Vein Stenosis due to the Insertion of a Temporal Right Subclavian Hemodialysis Catheter

Central vein stenosis/occlusion is a common well-described sequel to the placement of hemodialysis catheters in the central venous system. The precise mechanisms by which central vein stenosis occurs are not well known. Current concepts in central vein stenosis pathophysiology focus on the response to vessel injury model, emphasizing the process of trauma. A case of left brachiocephalic vein stenosis due to the insertion and function of a temporary right subclavian hemodialysis catheter is presented. The purpose of the manuscript is to emphasize that, with the introduction of a temporary subclavian hemodialysis catheter via the right subclavian vein apart from causing concurrent stenosis/infarction of the right subclavian and right brachiocephalic vein, it is also possible to cause stenosis of the left brachiocephalic vein (close to its contribution to the superior vena cava) although the catheter tip is placed in the correct anatomical position in the superior vena cava.

Long-term clinical outcomes of the single-incision technique for implantation of implantable venous access ports via the axillary vein

Purpose

To evaluate long-term clinical outcomes and complications of the single-incision technique for implantation of totally implantable venous access ports (TIVAPs) via the axillary vein.

Materials and Methods

A total of 932 TIVAPs were placed in 927 patients between May 2012 and October 2014 using a single-incision technique. Patients included 620 men and 307 women with a mean age of 60.0 years. TIVAPs were placed via the left (n = 475) and right (n = 457) axillary veins after making a single oblique vertical incision and medial side pocket without subcutaneous tunneling. We retrospectively reviewed medical records to evaluate status of the patients and TIVAPs, complications, and reasons for explantation. In patients who still had a TIVAP in place, we calculated the duration of TIVAP use from the cut-off day of November 1, 2015.

Results

Clinical follow-up was obtained for a total device service period of 311,069 days with a median indwelling time of 467 days (range: 3-1097 days). A total of 37 (4.0%) complications developed. Early complications (n = 4) were one case each of stenosis of the brachiocephalic vein by tumor growth, thrombosis of axillary vein, intravascular migration, and malfunction depending on patient's position. Late complications (n = 33) were suspected catheter-related blood stream infection (n = 23), local infection of the pocket (n = 4), symptomatic stenosis and thrombosis of central vein (n = 4), malfunction by fibrin sleeve (n = 1), and intravascular migration (n = 1).

Conclusions

A single-incision technique for TIVAP implantation via the axillary vein seems to be safe with a low risk of complication.

Treatment of central venous in-stent restenosis with repeat stent deployment in hemodialysis patients

Purpose

To report patency rates for stent deployment for treatment of in-stent stenosis of the central veins of the chest in hemodialysis patients.

Materials and Methods

A retrospective analysis was performed on 29 patients who underwent 35 secondary percutaneous transluminal stent (PTS) deployments for in-stent stenosis within the central veins that were refractory to angioplasty and ipsilateral to a functioning hemodialysis access (in-stent PTS group). For comparison, patency data were acquired for 47 patients who underwent 78 successful percutaneous transluminal angioplasty (PTA) procedures for in-stent stenosis (in-stent PTA group) and 55 patients who underwent 55 stent deployments within native central vein stenosis refractory to angioplasty (native vein PTS group).

Results

The 3-, 6-, and 12-month primary lesion patency for the in-stent PTS group was 73%, 57%, and 32%, respectively. The 3-, 6-, and 12-month primary patency for the in-stent PTA group was 70%, 38%, and 17% and for the native vein PTS group was 78%, 57%, and 26%, which were similar to the in-stent PTS group (p = 0.20 and 0.41, respectively). The 3-, 6-, and 12-month secondary access patency was 91%, 73%, and 65% for the in-stent PTS group. Sub-analysis of the in-stent PTS group revealed no difference in primary (p = 0.93) or secondary patency rates (p = 0.27) of bare metal stents (n = 23) compared with stent grafts (n = 12).

Conclusions

Stent deployment for central vein in-stent stenosis refractory to angioplasty was associated with reasonable patency rates, which were similar to in-stent PTA and native vein PTS.

Balloon-assisted venous access salvage through a thrombosed arteriovenous graft

INTRODUCTION

Maintaining vascular access by means of radiological intervention has become the mainstay of management of patients with central venous stenoses and occlusions (CVO), which can be challenging. We present a case of balloon-assisted percutaneous puncture of an occluded left subclavian vein, through a thrombosed arteriovenous graft, for a tunneled dialysis catheter insertion.

METHODS

A thrombosed left arm arteriovenous graft was accessed, and the occluded left subclavian vein was traversed with 0.018 platform. An 8 mm 0.018 low platform balloon was inflated in the left subclavian vein as a target for percutaneous puncture to gain direct access into the occluded segment of the vein. This access was then used for routine placement of a tunneled left subclavian dialysis catheter.

RESULTS

Successful placement of a tunneled dialysis catheter into an occluded left subclavian vein using a balloon- assisted puncture technique, through a thrombosed left-arm arteriovenous graft.

CONCLUSIONS

Thrombosed arteriovenous grafts are potential access sites into the central veins. Balloon-assisted punctures allow vascular access salvage into otherwise occluded segments of a central vein; in our case, it allowed access into an occluded left subclavian vein for dialysis catheter placement.

Hemodialysis Tunneled Catheter Noninfectious Complications

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined.

Early cannulation graft Flixene™ for conventional and complex hemodialysis access creation

PURPOSE

The Flixene™ (Atrium™, Hudson, NH) is a trilaminate composite polytetrafluoroethylene (PTFE) graft that allows access within 72 hours. We evaluate our initial experience with this device for conventional and complex hemodialysis access creation.

METHODS

Retrospective review in end-stage renal disease (ESRD) patients who underwent access creation with Flixene from January 2013 to July 2014. For our analysis, the patients were divided in two groups: those with complex access configurations tunneled in the chest and/or abdominal wall (thoraco-abdominal wall access [TAWA]), and those tunneled in conventional sites (extremity access [EA]). Patient's demographics, indications, complications, reinterventions, patency rates and factors influencing outcomes were evaluated.

RESULTS

In 19 patients (54% men; mean age 44 years ± 18), 24 grafts were implanted, (13 EA [54%] vs. 11 TAWA), all patent after surgery. Central venous occlusive disease (CVOD) was present in all patients with TAWA and in 7/13 (54%) EA patients (p = 0.016). Early cannulation (within 72 hours) was successful in 12 EA and 5 TAWA grafts (p = 0.044). Complication rates including infection, thrombosis, bleeding and steal syndrome were 8/11 (73%) in TAWA and 5/13 (38%) in EA (p = 0.02). At 12 months, primary patency rates for EA and TAWA were 25% and 41%; secondary patency rates were 55% and 41%, respectively.

CONCLUSIONS

Early cannulation (EC) grafts are viable alternatives for conventional and complex access creation that allowed early cannulation (<72 hours) in 17 (70%) of our cases. Primary and secondary patency rates at 12 months were equivalent to data reported on ePTFE grafts.

Left innominate vein stenosis in an asymptomatic population: a retrospective analysis of 212 cases

Background

Although left innominate vein (LIV) stenosis has been demonstrated to be attributed to compression by adjacent anatomical structures, most of the studies are focusing on hemodialysis patients with clinical symptoms compatible with LIV stenosis. The goal of this study was to retrospectively investigate the incidence of LIV stenosis and its influencing factors in an asymptomatic, non-hemodialysis population, which has rarely been performed.

Methods

From Jan 2013 to Dec 2014, 212 consecutive cases undergoing a chest multi-detector computed tomography (MDCT) angiography were enrolled. LIV stenosis was defined as loss of the area of the LIV (that is, 1 − compression degree) >25%. Multivariate logistic regression analysis was performed to explore the independent risk factors associated with LIV stenosis.

Results

LIV stenosis occurred in 35.4% of cases (75/212), with the median loss of the area of the LIV of 36.2% (interquartile range 30.2–49.8%). There were significant differences in age (62.5 ± 11.7 vs. 58.6 ± 14.3 years; P = 0.041), BMI (23.9 ± 2.9 vs. 23.0 ± 3.3, P = 0.036), the frequency of crossing site of LIV over the origin of the aortic arch (54.7 vs. 24.8%, P < 0.001), and the space between aortic arch and sternum [mean ± SD, 11.6 ± 4.2 mm vs. median, 14.1 (interquartile range 11.9–16.3) mm, P < 0.001] between patients with and without LIV stenosis, but only the latter two were confirmed as independent factors by the multivariate logistic regression analysis [crossing site of LIV over the aortic arch, OR (95% CI) = 2.632 (1.401, 4.944), P = 0.003; space between the aortic arch and sternum, OR (95% CI) = 0.841 (0.770, 0.919), P < 0.001].

Conclusion

The patients with an older age, high BMI, LIV crossing over the origin of the aortic arch, or smaller space between aortic arch and sternum may have high risks for LIV stenosis. They should be paid more attention to exclude LIV stenosis preoperatively using MDCT angiography to prevent venous access dysfunction and symptomatic development by fistula creation when hemodialysis is required.

Haemodialysis catheters in the intensive care unit

Ten to 15% of critically ill patients need renal replacement therapy (RRT) for severe acute kidney injury. The dialysis catheter is critical for RRT quality and efficiency. Catheters have several properties that must be optimized to promote RRT success. The distal tip has to be located in a high blood flow location, which means central venous territory. Therefore, catheters are mostly inserted into the right internal jugular vein or in femoral veins. External diameter should vary from 12 to 16 Fr in order to ensure adequate blood flow inside the catheter. Lumen shapes are theoretically designed to limit thrombotic risk with low turbulences and frictional forces against the internal wall. With low aspiration pressure, distal tip shape has to deliver sufficient blood flow, while limiting recirculation rate. Catheter material should be biocompatible. Despite in vitro data, no strong evidence supports the use of coated catheters in the ICU in order to reduce infectious risk. Antibiotic "lock" solutions are not routinely recommended. Ultrasound guidance for catheterization significantly decreases mechanical complications. Clinicians should select the optimal catheter according to patient body habitus, catheter intrinsic properties and RRT modality to be used.

Hemodialysis Tunneled Catheter Noninfectious Complications

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined.

Early infection risk with primary versus staged Hemodialysis Reliable Outflow (HeRO) graft implantation

OBJECTIVE

This study evaluated whether the use of a staged Hemodialysis Reliable Outflow (HeRO; Merit Medical, South Jordan, Utah) implantation strategy incurs increased early infection risk compared with conventional primary HeRO implantation.

METHODS

A retrospective review was performed of 192 hemodialysis patients who underwent HeRO graft implantation: 105 patients underwent primary HeRO implantation in the operating room, and 87 underwent a staged implantation where a previously inserted tunneled central venous catheter was used for guidewire access for the venous outflow component. Within the staged implantation group, 32 were performed via an existing tunneled hemodialysis catheter (incidentally staged), and 55 were performed via a tunneled catheter inserted across a central venous occlusion in an interventional radiology suite specifically for HeRO implantation (intentionally staged). Early infection was defined as episodes of bacteremia or HeRO infection requiring resection ≤30 days of HeRO implantation.

RESULTS

For staged HeRO implantations, the median interval between tunneled catheter insertion and conversion to a HeRO graft was 42 days. The overall HeRO-related infection rate ≤30 days of implantation was 8.6% for primary HeRO implantation and 2.3% for staged implantations (P = .12). The rates of early bacteremia and HeRO resection requiring surgical resection were not significantly different between groups (P = .19 and P = .065, respectively), nor were age, gender, laterality, anastomosis to an existing arteriovenous access, human immunodeficiency virus status, diabetes, steroids, chemotherapy, body mass index, or graft location. None of the patient variables, techniques, or graft-related variables correlated significantly with the early infection rate.

CONCLUSIONS

The staged HeRO implantation strategy did not result in an increased early infection risk compared with conventional primary implantation and is thus a reasonable strategy for HeRO insertion in hemodialysis patients with complex central venous disease.

Vitamin K antagonists in children with central venous catheter on chronic haemodialysis: a pilot study

BACKGROUND

To date, no study has investigated the use of vitamin K antagonists (VKA) in children undergoing chronic haemodialysis (HD) with a central venous catheter (CVC).

METHODS

Consecutive patients aged <18 years with a newly placed tunnelled CVC for chronic HD were enrolled over a 3-year period. Children with active nephrotic syndrome or a history of venous thrombosis received warfarin (VKA group) with therapeutic target international normalised ratios of between 2.0 and 3.0. Patients at standard risk of CVC malfunction were not treated with VKA (standard group). The primary end-point was overall CVC survival.

RESULTS

The VKA group consisted of nine patients (median age 10.6 years; range 1.2-15.3 years) with 11 CVC, and the standard group comprised eight patients (11.8 years; 6.1-17.3 years) with ten CVC. The 6- and 12-month CVC survival was significantly longer in the VKA group than in the standard group (100 vs. 60 % and 83.3 vs. 16.7 %, respectively; p < 0.05), with a median survival of 369 and 195 days, respectively (p < 0.05). None of the CVC in the VKA group required removal due to malfunction, as compared to four in the standard group. No major bleeding episodes occurred in either group.

CONCLUSIONS

Therapy with VKA would appear to be safe in children on chronic HD and may improve CVC survival in patients at increased risk of CVC thrombosis.

Epidemiology of haemodialysis catheter complications: a survey of 865 dialysis patients from 14 haemodialysis centres in Henan province in China

OBJECTIVES

To investigate the incidence rates and risk factors for catheter-related complications in different districts and populations in Henan Province in China.

DESIGN

Cross-sectional.

SETTING

Fourteen hospitals in Henan Province.

PARTICIPANTS

865 patients with renal dysfunction undergoing dialysis using catheters between October 2013 and October 2014.

MAIN OUTCOME MEASURES

The main outcome measures were complications, risk factors and patient characteristics. Catheter-related complications included catheter-related infection (catheter exit-site infection, catheter tunnel infection and catheter-related bloodstream infection), catheter dysfunction (thrombosis, catheter malposition or kinking, and fibrin shell formation) and central vein stenosis.

RESULTS

The overall incidence rate was 7.74/1000 catheter-days, affecting 38.61% of all patients, for catheter infections, 10.58/1000 catheter-days, affecting 56.65% of all patients, for catheter dysfunction, and 0.68/1000 catheter-days, affecting 8.79% of all patients, for central vein stenosis. Multivariate analysis showed that increased age, diabetes, primary educational level or below, rural residence, lack of a nephropathy visit before dialysis and pre-established permanent vascular access, not taking oral drugs to prevent catheter thrombus, lower serum albumin levels and higher ferritin levels were independently associated with catheter infections. Rural residence, not taking oral drugs to prevent thrombus, lack of an imaging examination after catheter insertion, non-tunnel catheter type, lack of medical insurance, lack of nephropathy visit before dialysis and pre-established permanent vascular access, left-sided catheter position, access via the femoral vein and lower haemoglobin level were independently associated with catheter dysfunction. Diabetes, lack of nephropathy visit before dialysis and pre-established permanent vascular access, lack of oral drugs to prevent catheter thrombus, left-sided catheter location and higher number of catheter insertions, were independently associated with central vein stenosis.

CONCLUSIONS

The rate of catheter-related complications was high in patients with end-stage renal disease in Henan Province. Our finding suggest that strategies should be implemented to decrease complication rates.

The Role of Endovascular Stents in Dialysis Access Maintenance

Vascular stenosis is most often the culprit behind hemodialysis vascular access dysfunction, and although percutaneous transluminal angioplasty remains the gold standard treatment for vascular stenosis, over the past decade the use of stents as a treatment option has been on the rise. Aside from the 2 Food and Drug Administration-approved stent grafts for the treatment of venous graft anastomosis stenosis, use of all other stents in vascular access dysfunction is off-label. Kidney Disease Outcomes Quality Initiative recommends limiting stent use to specific conditions, such as elastic lesions and recurrent stenosis; otherwise, additional adapted indications are in procedure-related complications, such as grade 2 and 3 hematomas. Published reports have shown the potential use of stents in a variety of conditions leading to vascular access dysfunction, such as venous graft anastomosis stenosis, cephalic arch stenosis, central venous stenosis, dialysis access aneurysmal elimination, cardiac implantable electronic device-induced stenosis, and thrombosed arteriovenous grafts. Although further research is needed for many of these conditions, evidence for recommendations has been clear in some; for instance, we know now that stents should be avoided along cannulation sites and should not be used in eliminating dialysis access aneurysms. In this review article, we evaluate the available evidence for the use of stents in each of the aforementioned conditions leading to hemodialysis vascular access dysfunctions.

Is there an association between central vein stenosis and line infection in patients with tunnelled central venous catheters (TCVCs)?

PURPOSE

Central vein stenosis (CVS) and line infection are well-recognized complications of tunnelled central venous catheters (TCVCs) in patients on haemodialysis. The aim of this study was to evaluate any relationship between CVS and line infection.

METHODS

Analysis of 500 consecutive patients undergoing TCVC insertion was undertaken. Data were collected on patient demographics, details of line insertion and duration, culture-proven bacteraemia and presence of symptomatic CVS. Logistic regression analysis was used to determine risk factors for CVS and bacteraemia.

RESULTS

Mean patient age was 59.0 years (range: 17-93). Mean number of catheter days was 961.1 ± 57.6 per TCVC; 39.4% of TCVCs were associated with culture-proven bacteraemia and 23.6% developed symptomatic CVS. Bacteraemia and CVS were inevitable complications of all TCVCs. The time to symptomatic CVS was longer in patients with bacteraemia than without (1230.91 ± 101.29 vs. 677.49 ± 61.59 days, p<0.001). Patients who had early infection within 90 days of TCVC insertion were less likely to develop CVS (5.9% vs. 22.8%, p<0.001). There was no difference in the bacteraemia rate per 1,000 catheter days between patients with and without CVS (2.62 ± 1.41 vs. 2.35 ± 0.51; p = 0.98). Number of line days (odds ratio (OR) 1.02, p = 0.003), age (OR 1.04, p = 0.04) and culture-proven line infection (OR 0.59, p = 0.014) were all independently associated with CVS.

CONCLUSIONS

Our results suggest that early line infection may be protective against CVS. Alternatively, there may be two distinct predisposition states for CVS and line infection. Further studies are needed to confirm our association and investigate causation.

Avoiding the use of a femoral bridging catheter using a two-stage Hemodialysis Reliable Outflow (HeRO) graft implantation technique

PURPOSE

To evaluate a two-stage Hemodialysis Reliable Outflow (HeRO) implantation technique that avoids the use of a femoral bridging catheter versus the conventional one-stage technique requiring a bridging catheter in selected patients.

METHODS

A retrospective review was performed on 20 end-stage renal disease patients with an internal jugular vein (IJV) catheter selected for two-stage HeRO implantation at our institution between January 2010 and March 2013. The arterial graft component (AGC) was implanted without anastomosing it to the target artery (first stage). After AGC incorporation, the venous outflow component was inserted (second stage). The preexisting IJV catheter was maintained for hemodialysis access during the interstage period. Patient characteristics, patency using Kaplan-Meier method and infection rates were analyzed.

RESULTS

A total of 17 patients with a mean age of 59 years (70.6% women) completed the two-stage procedure. During the interstage period (mean 12 weeks, range 4-22 weeks), no graft- or surgery-related infection occurred. The need of a femoral bridging catheter was avoided by utilizing the preexisting IJV dialysis catheter. The accumulated HeRO days were 3,916 days with a mean follow-up of 7.7 months (range 1-22.6 months). The HeRO-related infection rate was 0.3/1,000 days. The primary assisted and secondary patency rates at 6 months were 69% and 82%, respectively, which were similar to those of arteriovenous grafts. Staging conferred immediate vascular accessibility.

CONCLUSIONS

Avoiding the use of a femoral bridging catheter using the two-stage technique may lower infection rate, with comparable primary assisted and secondary patency to arteriovenous grafts and added benefit of immediate cannulatability in this subset of patients.

Anticoagulation treatments related different types of vascular access on maintenance hemodialysis patient: A multicenter epidemiological investigation

Objective

The objective was to increase the understanding of vascular access in hemodialysis and evaluate hemodialysis-related anticoagulation treatments and the associated hemorrhagic or thrombotic complications.

Materials and Methods

In this study, an epidemiological investigation was conducted in 1175 patients who underwent hemodialysis in seven blood purification centers in northern Chinese. The patients were divided into two groups based on the vascular access they used: Arteriovenous fistula (AVF) group and central venous catheter (CVC) group. The similarities and differences of anticoagulation and hemorrhagic, thrombotic complications were compared between two groups.

Results

Arteriovenous fistula was the most frequently used vascular access, and heparin was the most commonly used anticoagulant. Patients in CVC group experienced significantly greater rates of low molecular weight heparin (LMWH) administration and had a higher rate in achieving thrombotic complications than those in AVF group. There were no significant differences in LMWH dosages in patients with thrombotic complications, as well as the proportion of patients who received anti-platelet drugs. Heparinized catheter lock solutions were excessively high in this study, which may lead to a risk of hemorrhage.

Conclusion

Hemodialysis-related anticoagulation treatments in China require additional improvements, especially for the patients using CVC as vascular access. There is an urgent need to develop clinical evaluation studies of anticoagulation treatments for achieving more standardized and targeted treatments.

Bilateral Central Vein Stenosis: Options for Dialysis Access and Renal Replacement Therapy when all upper Extremity Access Possibilities have been Lost

Purpose

Patients with bilateral central vein stenosis present a unique challenge: treatment options are limited, largely unproven and associated with reputedly poor outcomes. Our aim was to compare patency rates of different access and renal replacement treatment (RRT) modalities in patients with bilateral central vein stenosis/occlusion.

Material and methods

Data on all patients presenting to a tertiary referral vascular access centre with end-stage vascular access (defined by bilateral central vein stenosis/occlusion with loss of upper limb access) over a 5-year period were included. 3, 6 and 12-month patencies of translumbar catheters (TLs), tunnelled femoral catheters (Fem), native long saphenous vein loops (SV), prosthetic mid-thigh loop grafts (ThGr), peritoneal dialysis (PD), and expedited donation after cardiac death (DCD) cadaveric renal transplants (Tx) via local allocation policies were compared using log-rank test. Kaplan–Meier survival analysis was used to estimate long-term access survival.

Results

One hundred forty-six vascular access modalities were attempted in 62 patients (62 Fem, 25 TL, 15 SV, 25 ThGr, 8 PD, 11 Tx). Median follow-up was 876±57 days. Three, 6 and 12-month primary-assisted patencies for each modality were as follows: Fem: 75.4%, 60% and 28%; TL: 88%, 65% and 50%; SV: 87.5%, 60% and 44.6%; ThGr: 64%, 38% and 23.5%; PD: 62.5%, 62.5% and 50%; Tx: 72.7%, 72.7% and 72.7%. SV had better secondary patency at 900 days (76.9%) than ThGr (49.2%) or Fem (35.8%) (p<0.01). No patients died as a result of loss of access.

Conclusion

Patients with bilateral central vein stenosis often require more than one vascular access modality to achieve a “personal access solution.” Native long saphenous vein loops provided the best long-term patency. Expedited renal transplantation with priority local allocation of DCD organs to patients with precarious vascular access provides a potential solution to this difficult problem.

Comparison of Flixene™ and Standard PTFE Arteriovenous Graft for Early Haemodialysis

Purpose

The purpose is to compare the outcomes of FLIXENE™ arteriovenous graft (AVG) to standard polytetrafluoroethylene (PTFE) AVG for early haemodialysis.

Methods

This is a prospective observational study of all AVGs placed over a 40-month period between 2008 and 2011 at our vascular unit. Primary outcome was to examine early cannulation rates for FLIXENE™. Secondary outcomes included patency rates, usability of grafts, complications in particular infections, interventions and death in comparison to standard PTFE grafts.

Results

Forty-five FLIXENE™ and 19 standard PTFE AVGs were placed in the study period; 89% of FLIXENE™ grafts were used for dialysis, with 78% cannulated within 3 days. At 18 months, primary patency (FLIXENE™ 34% vs standard PTFE 24%), primary assisted patency (35% vs 36%) and secondary patency rate (51% vs 48%) were not statistically different; 20.2% of FLIXENE™ grafts were infected at 18 months requiring explantation compared with 40.3% of standard PTFE grafts (p=0.14).

Conclusions

FLIXENE™ can be cannulated for dialysis within 3 days. It has similar patency and complication rates as other prosthetic grafts in the market. In patients who have no access and require urgent dialysis, FLIXENE™ is a viable option.

Use of tissue plasminogen activator in catheters used for extracorporeal renal replacement therapy

Background

Intraluminal thrombosis of central venous catheters used for renal replacement therapy (RRT) decreases the ability to provide adequate treatment. Alteplase is a recombinant tissue plasminogen activator that has been used to improve the function of catheters used for RRT in humans.

Objectives

To retrospectively review alteplase instillation in dysfunctional catheters used for RRT in dogs and cats.

Animals

Seventeen dogs and 8 cats receiving RRT for kidney failure.

Methods

Medical records of patients in which alteplase was used for RRT catheter dysfunction from 2004 to 2012 were retrospectively reviewed to characterize reasons for use, improvement in function, increase in blood flow, and duration of improvement.

Results

Alteplase was instilled 43 times in 29 catheters, most commonly because of suspicion that the catheter would not provide sufficient flow on the next treatment (n = 21). The second most common reason was inability to start a dialysis treatment (n = 12). Catheter function improved after alteplase instillation in 34 of 43 treatments (79%). Median blood flow rate increased by 13% (18 mL/min) in the dialysis session after alteplase instillation. Seven of 29 catheters (24%) were treated with alteplase on >1 occasion (median time to second treatment, 8 days), and 1 catheter had to be replaced because of intractable dysfunction.

Conclusions and Clinical Importance

Alteplase is effective at improving function of central venous catheters used to provide RRT, but the results are short‐lived.

Fibrin sheath angioplasty: a technique to prevent superior vena cava stenosis secondary to dialysis catheters

Fibrin sheaths are a heterogeneous matrix of cells and debris that form around catheters and are a known cause of central venous stenosis and catheter failure. A total of 50 cases of central venous catheter fibrin sheath angioplasty (FSA) after catheter removal or exchange are presented. A retrospective review of an outpatient office database identified 70 eligible patients over a 19-month period. After informed consent was obtained, the dialysis catheter exiting the skin was clamped, amputated, and a wire was inserted. The catheter was then removed and a 9-French sheath was inserted into the superior vena cava, a venogram was performed. If a fibrin sheath was present, angioplasty was performed using an 8 × 4 or 10 × 4 balloon along the entire length of the fibrin sheath. A completion venogram was performed to document obliteration of the sheath. During the study, 50 patients were diagnosed with a fibrin sheath, and 43 had no pre-existing central venous stenosis. After FSA, 39 of the 43 patient's (91%) central systems remained patent without the need for subsequent interventions; 3 patients (7%) developed subclavian stenoses requiring repeat angioplasty and stenting; 1 patent (2.3%) developed an occlusion requiring a reintervention. Seven patients with prior central stenosis required multiple angioplasties; five required stenting of their central lesions. Every patient had follow-up fistulograms to document long-term patency. We propose that FSA is a prudent and safe procedure that may help reduce the risk of central venous stenosis from fibrin sheaths due to central venous catheters.

Central vein stenosis

Central vein stenosis (CVS) is commonly seen in patients receiving hemodialysis through an arteriovenous access, threatening the usability of arteriovenous access for dialysis. Subclavian and internal jugular catheters are prime reasons for the development of CVS, especially in the setting of long-term use of multiple catheters. CVS related to cardiac rhythm devices also is seen frequently. Idiopathic CVS can be encountered, although it is less common. Clinical features ultimately become sufficiently prominent to prompt angiographic evaluation. CVS should be evaluated carefully because management must be individualized. The primary method for treatment of CVS is endovascular intervention, including angioplasty and stent placement, whereas surgical options should be pursued in only refractory cases due to the invasiveness of the intervention. Early referral of patients for chronic kidney disease care; timely discussion of kidney replacement modality choices, including nonhemodialysis options such as peritoneal dialysis and kidney transplantation; placement of arteriovenous access prior to the onset of dialysis; and avoidance of catheters and other central vein instrumentation will prevent the development of CVS in most patients with kidney disease.

Killing Two Birds with One Stone: Subclavian Vein Bypass Graft for Relief of Venous Obstruction and Haemodialysis Access

Subclavian and brachio-cephalic vein stenosis or occlusion occurs, most commonly, as an iatrogenic complication of the placement of central venous catheter. This occurrence can cause ipsilateral arm swelling in a newly-created arteriovenous fistula (AVF). Critical central vein stenoses are often successfully managed by endovascular approach; occasionally, complete occlusion with symptomatic severe arm swelling and pain that does not respond to angioplasty requires ligation of the dialysis access. We report successful surgical management of an end-stage-renal-failure (ESRF) patient with symptomatic subclavian vein occlusion refractory to angioplasty in an ipsilateral arm with an existing functional brachio-basilic transposition arteriovenous fistula by performing a basilic to internal jugular vein (IJV) bypass graft, relieving both the arm swelling and salvaging the existing vascular access for future haemodialysis.