Restoration of Patency in Failing Tunneled Hemodialysis Catheters: A Comparison of Catheter Exchange, Exchange and Balloon Disruption of the Fibrin Sheath, and Femoral Stripping

Assessment of dysfunctional tunneled hemodialysis catheters and outcome of endovascular salvage techniques: a simple solution to a complex problem

Objective

The aim of this study was to evaluate the causes of the dysfunctional tunneled cuffed catheters (TCCs) using multi-spiral computed tomography venography (MSCTV), and to analyze the outcomes of endovascular salvage techniques.

Material and methods

This retrospective review data from 27 patients who experienced TCC dysfunction between July 1, 2016 and January 31, 2021 was conducted. Patients' demographic data, clinical signs and symptoms, and imaging data were collected from interventional radiology database.

Results

MSCTV showed a range of abnormalities in the hemodialysis (HD) patients, including central venous occlusion (n = 4), fibrin sheath formation (n = 3), malposition of the catheter tips (n = 4), central venous perforation (n = 1), thrombus formation (n = 12), regular catheter exchange without determined lesions (n = 3). Interventional catheter salvage procedures were performed, such as catheter exchange, balloon disruption of a fibrin sheath, angioplasty for central vein stenosis, and stent deployment. The technical success rate for catheter insertions was 100%, and no procedure-related severe complications were observed. The 30-day catheter patency for all assessable catheters was 85.2%.

Conclusion

The use of MSCTV showed abnormal findings in almost 88.9% of cases concerning dysfunctional TCC. In this study, the examined appropriate endovascular techniques were found to be safe and technically successful, with a low incidence of procedure-related complications.

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.

Fibrin sheath disruption during guidewire exchange for bacteremia: Low recurrence of infection and preservation of vascular access sites

BACKGROUND

Catheter-associated bacteremia (CAB) often leads to removal of tunneled dialysis catheters with delayed insertion (RDI). Exchange over a guidewire (ExW) can be considered for access site preservation. Fibrin sheath disruption (FSD) during exchange is not standard practice for infected catheters. Here we present the first analysis of outcomes after such exchanges (ExW-FSD).

METHODS

Retrospective analysis of catheter exchanges and removals performed by interventional nephrology for bacteremia in 2008-2011 observed for 20.5 months. Charts were reviewed for recurrent or new bacteremia and death at 3 months, and for occurrence of thrombosis or stenosis along the catheter site. Catheter exchange with central venogram and fibrin sheath disruption was our standard of care in all patients presenting for CAB. RDI was performed either for tunnel infection, non-clearing of infection or at the request of referring physicians.

RESULTS

Over 4 years, 66 patients were treated for CAB. Forty-two patients underwent ExW-FSD, which was performed even for Staph. aureus, gram negative bacteremia or candidemia. RDI was performed in 24 cases. Bacteremia recurred in 3 (7%) patients after ExW-FSD, and in 7 (30%) cases after RDI (p = 0.02). There was no significant difference in new infections: 5 (12%) after ExW-FSD and 2 (8%) after RDI. There was no death within 3 months after ExW-FSD and 4 (27%) (p = 0.005) deaths in the RDI group.There was one new central venous stenosis in the ExW-FSD group (2%) with no loss of access site, and 8 (33%) patients developed thrombosis/stenosis along the prior catheter track after RDI (33%) (p = 0.006) with loss of access site in (21%).

CONCLUSIONS

In this retrospective analysis of treatment of CAB, ExW-FSD was associated with lower recurrence of bacteremia, lower death rate and a lower incidence of access site loss compared to RDI. These data support ExW-FSD use in patients with CAB.

Replacement Versus Same-Site Salvage Using Hickman Catheter for Pediatric Stem Cell Transplantation Patients: A Comparative Study

BACKGROUND

Children undergoing bone marrow transplant need a double-lumen Hickman line. Therefore, changing Port-a-Cath ports to double-lumen Hickman catheter is mandatory. Several methods were described for changing Port-a-Cath ports either through the same-site or a new placement access site. The advantage of one method over the other is still debatable. We conducted this study to compare the safety and effectiveness of replacement versus salvage techniques to change ports to the Hickman lines before bone marrow transplants in pediatric patients.

METHODS

We included 85 pediatric patients who underwent stem cell transplants. Their age ranged from 0.2 to 15 years. According to the Hickman reinsertion technique, we classified the patients into 2 groups; the Replacement group (n = 47) and the Same-site salvage group (n = 38). We compared the data before and after Hickman insertion between both groups. Study outcomes were the catheter duration, its complications, and mortality.

RESULTS

The mean age of all patients was 4.7 ± 3.9 years, and 65.9% were males. There was no difference in the baseline data between both groups. During Port-a- Cath first insertion; 16.5% of patients suffered complications, with 10.6% had conversion to cut down, 1.2% had a hematoma, and 4.7% had multiple site insertion. We did not report differences between groups in the complications of the first port insertion. The Hickman duration was longer in the replacement group (4 (Q1-Q2: 2-6) vs. 1 (0.5-3) months, P = 0.005). Increased age (odds ratio [OR]: 1.31, P = 0.001) and male gender (OR: 1.19, P = 0.046) were independent predictors of mortality.

CONCLUSIONS

Endovascular same-site salvage technique could help preserve vascular access during the tunnel catheter exchange for noninfectious reasons. We recommend the use of the same-site salvage technique in pediatric transplant patients.

Computed Tomography (CT)-Navigated Translumbar Hemodialysis Catheters: A 10-Year Single-Center Experience

BACKGROUND In dialysis patients with exhausted usual central venous access sites, the translumbar hemodialysis catheter (TLC) provides a viable option for dialysis access. The technical success of catheter insertion, associated complications, and long-term patency of TLC were evaluated in this study. MATERIAL AND METHODS This retrospective study included 37 patients with occluded central thoracic veins in whom 39 TLC implantation procedures were performed and 196 patients with internal jugular vein hemodialysis catheters (JVC). TLC implantation was performed as a hybrid procedure with computed tomography (CT)-navigated translumbar inferior vena cava cannulation and subsequent fluoroscopy-guided hemodialysis catheter placement. RESULTS The rates of technical success of the implantations and minor periprocedural complications were 97.4% and 10.3% in the TLC group and 98.6% and 4.2% in the JVC group, respectively. The median follow-up in the TLC and JVC groups was 673 days and 310 days, respectively. The primary-assisted patency at the 1-year and 3-year follow-up was 88.7% and 72.0% in the TLC group and 81.6% and 67.0% in the JVC group, respectively, with no statistically significant difference between the 2 groups. The incidence rate of infection-related and patency-related complications calculated for 1000 catheter-days was 0.15 and 0.11 in the TLC group and 0.33 and 0.25 in the JVC group, respectively. CONCLUSIONS The CT-guided implantation of the TLC is a useful option to create dialysis access with a low complication rate and satisfactory long-term patency in patients without usual venous access.

The fibroblastic sleeve, the neglected complication of venous access devices: A narrative review

The presence of a vascular access device (or of any intravascular foreign body) inside the bloodstream is often associated with the formation of a connective tissue sleeve around the catheter (often named-erroneously-"fibrin sleeve"). Such sleeve is usually a physiological phenomenon with little or no clinical relevance, but its pathogenesis is still unclear, so that it is frequently confused with venous thrombosis; also, its relationship with other major catheter-related complications, such as venous thrombosis and bloodstream infection, is uncertain. This narrative review tries to convey in a systematic form the current knowledge about pathogenesis, incidence, clinical manifestations, diagnosis, and management of this phenomenon.

Non-invasive tunnelled catheter reposition (NTCR): A simple and safe method to restore central tunnelled catheter function for haemodialysis

Despite all efforts, still many end-stage kidney disease (ESKD) patients are dialysed using a central tunnelled catheter (CTC) as vascular access. When the CTC blood flow becomes ineffective, a number of protocols are advised. However, all of them are time- and cost-consuming. The manoeuvre of a non-invasive tunnelled catheter reposition (NTCR) was introduced to restore the CTC function. NTCR was based on gentle movements of the CTC, with or without a simultaneous flushing of the CTC lines, which resulted in a quick reposition of the CTC tip. This study comprises the analysis of a total of 297 NTCRs, which were performed in 114 patients, thus enabling an effective blood flow after 133 procedures (44.7%).Partially effective blood flow followed 123 procedures (41.4%), and it failed altogether in 41 cases (13.9%). Overall, 86% of conducted NTCRs improved the CTC patency to perform a haemodialysis session. The procedure could be successfully repeated, with a similar result after the first and the second attempt. Complications were observed only after 3.4% of all interventions. The novel NTCR manoeuvre was safe and effective in the majority of the CTC dysfunction episodes. It seemed to reduce fibrinolytic usage, allowed an immediate haemodialysis session commencement, therefore, it might save both the costs and the nursing staff time.

Challenges of Vascular Access in the Pediatric Population

The incidence and prevalence of renal replacement therapy has continued to increase in the pediatric population. Recent data have shown that hemodialysis was the most frequently used dialysis modality, especially in pediatric ESRD patients (age 0-21 years). A well-functioning vascular access is required for effective hemodialysis and choosing the best vascular access option for pediatric patients can be difficult. Pediatric vascular options include arteriovenous fistula, arteriovenous graft, and central venous catheters (CVCs). There is a national initiative for fistula first-catheter last approach; however, CVCs have been reported as the most conventionally utilized vascular access option in pediatric patients. The use of CVCs should be minimized or avoided as they are associated with high risk of infections, thrombosis, and other complications. Thus, it is important for practitioners to plan appropriately in advance, practice good clinical judgment, and assure that the best vascular access is placed according to the patient's needs. Therefore, this article reviews the different types of pediatric vascular access and the associated benefits and potential complications of each.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

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.

TuLIP (Tunnelled Line Intraluminal Plasty): An Alternative Technique for Salvaging Haemodialysis Catheter Patency in Fibrin Sheath Formation

Background

Renal patients with a tunnelled haemodialysis line are at risk of fibrin ‘sheath’ formation which can lead to occlusion. Dysfunctional lines are best treated by catheter exchange with a new subcutaneous tunnel; however, there is a risk of scarring, venous stenosis, potential loss of valuable access as well as the risk of infection.

Method

We report a retrospective review of our experience using tunnelled line intraluminal plasty (TuLIP) in 11 patients over 16 months with fibrin sheath formation on pre-existing tunnelled haemodialysis catheters.

Result

All patients responded well to treatment with median line patency post TuLIP reaching 112 days.

Conclusion

TuLIP may have a role in extending catheter lifespan and delaying more invasive intervention.

Patency rates of dysfunctional central hemodialysis venous catheter: Comparison between catheter exchange alone and catheter exchange with fibrin sheath angioplasty

PURPOSE

The purpose of this study was to compare patency rates and risk of obstruction of catheter exchange (CE) with that of CE with fibrin sheath angioplasty (CE+FSA) in dysfunctional tunneled central hemodialysis venous catheter (CHVC).

MATERIALS AND METHODS

A total of 107 consecutive patients with dysfunctional CHVC were retrospectively included. There were 66 men and 41 women with a mean age of 67.8±12.5 (SD) years (range: 23.0-86.0 years). Seventy-three of 107 patients (68.2%) underwent CE procedure and 34 of 107 (31.8%) underwent CE+FSA. Kaplan-Meier log-rank test and multivariate Cox regression analyses were performed to determine patency rates and risk of obstruction according to type of endovascular procedure.

RESULTS

Patency rates after endovascular procedures at 3, 6, 12, 24 and 36 months follow up were 75%, 75%, 65%, 65% and 65% in CE+FSA group and 70%, 65%, 62%, 30% and 0% in CE group. Mean time until obstruction of CHVC was 778.4 days after CE+FSA and 497 days after CE (P=0.211). Endovascular procedure was unrelated to risk of obstruction in adjusted model (HR=1.34; P=0.515).

CONCLUSIONS

Our findings suggest that both techniques are equivalent in terms of patency and safety results, so other aspects as cost assessment should be considered when choosing between both techniques.

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.

A Prospective Clinical Study of a Percutaneous Vascular Access System for Hemodialysis Catheters

INTRODUCTION

Dysfunctional or infected hemodialysis polyester-cuffed catheters often require removal and are dissected out. The DermaPort™, percutaneous vascular access system (PVAS) permanently integrates a titanium mesh with the skin forming a stable, sterile barrier that allows for catheter placement, adjustment, or catheter exchange. This study aimed to describe the use and clinical outcomes of the DermaPort PVAS.

METHODS

Thirty-eight patients who were receiving hemodialysis via a tunneled catheter were enrolled in this prospective open-label study. Assessments were performed biweekly for the first month and monthly thereafter, which included physical examination of the site of implantation for infection, catheter blood flow, and need for interventions to maintain catheter patency. Patient satisfaction was assessed with a visual analog score.

RESULTS

Implantation of technical success was 100% with the implantation site demonstrating early tissue incorporation after 2 weeks and full incorporation within 4 weeks. The DermaPort™ successfully enabled 31 catheter exchanges and 10 repositions thru the port without dissection in 18 patients with nine repositions (90%) performed at bedside. The mean primary patency of the DermaPort™ was 172 ± 150 days, and mean secondary patency was 430 ± 203 days. There were no reportable serious adverse events in 12,100 catheter days of use and zero explantations of the device attributed to infection. The observed catheter infection rate was 0.33/1000 days.

CONCLUSIONS

The DermaPort™ system can be effectively implanted and facilitates catheter interventions in hemodialysis patients requiring long-term catheter use and has a lower infection rate than historical catheter infection rates. Clinical Trial Protocol Number DermaPort-001 (no clinicaltrials.gov number as study was performed 9 years ago). Health Canada Reference Application Number: 118393.

ACR Appropriateness Criteria® Radiologic Management of Central Venous Access

Obtaining central venous access is one of the most commonly performed procedures in hospital settings. Multiple devices such as peripherally inserted central venous catheters, tunneled central venous catheters (eg, Hohn catheter, Hickman catheter, C. R. Bard, Inc, Salt Lake City UT), and implantable ports are available for this purpose. The device selected for central venous access depends on the clinical indication, duration of the treatment, and associated comorbidities. It is important for health care providers to familiarize themselves with the types of central venous catheters available, including information about their indications, contraindications, and potential complications, especially the management of catheters in the setting of catheter-related bloodstream infections. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Fibrin sheaths in central venous port catheters: treatment with low-dose, single injection of urokinase on an outpatient basis

Purpose

Evaluation of the efficacy of single-shot, low-dose urokinase administration for the treatment of port catheter-associated fibrin sheaths.

Methods

Forty-six patients were retrospectively evaluated for 54 episodes of port catheter dysfunction. The presence of a fibrin sheath was detected by angiographic contrast examinations. On an outpatient basis, patients subsequently received thrombolysis consisting of a single injection of urokinase (15.000 IU in 1.5 mL normal saline) through the port system. A second attempt was made in cases of treatment failure. Patients were followed up for technical success, complications and long-term outcome.

Results

Port dysfunction occurred at a median of 117 days after implantation (range: 7–825 days). The technical success after first port dysfunction by thrombolysis was 87% (40/46); thereof, initial thrombolysis was effective in 78% (36/46). Nine patients (20%) received a second dose of urokinase after previous treatment failure. Follow-up was available for 26 of 40 patients after successful thrombolysis. In 8 of these, rethrombosis occurred after a median of 98 days (range: 21–354 days), whereby rethrombolysis was effective in 5 of 7 (63%) patients. The overall success of all thrombolyses performed was 70% (45/64). No procedure-related technical or clinical complications occurred. After first favorable thrombolysis, a Kaplan–Meier analysis yielded a 30-, 90- and 180-day probability of patency of 96%, 87% and 81%.

Conclusion

Thrombolytic therapy on an outpatient basis appears to be a safe and efficient. Three-month patency rates are comparable to more invasive treatment options, including catheter exchange over a guide wire and percutaneous fibrin sheath stripping.

Update on Insertion and Complications of Central Venous Catheters for Hemodialysis

Central venous catheters are a popular choice for the initiation of hemodialysis or for bridging between different types of access. Despite this, they have many drawbacks including a high morbidity from thrombosis and infection. Advances in technology have allowed placement of these lines relatively safely, and national guidelines have been established to help prevent complications. There is an established algorithm for location and technique for placement that minimizes harm to the patient; however, there are significant short- and long-term complications that proceduralists who place catheters should be able to recognize and manage. This review covers insertion and complications of central venous catheters for hemodialysis, and the social and economic impact of the use of catheters for initiating dialysis is reviewed.

Air embolism during insertion and replacement of tunneled dialysis catheters: a retrospective investigation of the effect of aerostatic sheaths and over-the-wire exchange

PURPOSE

To determine the impact of the introduction of aerostatic sheaths on air embolism (AE) events during tunneled dialysis catheter (TDC) insertion and to characterize such events occurring during over-the-wire exchange (OTWE).

MATERIALS AND METHODS

Between July 2001 and April 2013, 5,789 TDCs were placed, including 3,963 de novo placements, 1,811 OTWEs, and 15 tract recanalizations. There were 15 AE events reported, and the medical records of these patients were reviewed. The effect of aerostatic sheaths, introduced in July 2005, was compared with the period before their introduction; the same TDC design was used throughout.

RESULTS

Of the 15 AE events, 10 occurred during de novo placement (10 of 3,963 placement; 0.25%), 4 occurred during OTWE (4 of 1,811 placements; 0.22%), and 1 occurred during tract recanalization. With regard to aerostatic sheaths in de novo TDC placement, 4 of 1,174 (0.34%) AE events occurred before aerostatic sheath introduction, and 6 of 2,789 (0.22%) AE events occurred after aerostatic sheath introduction. These rates did not differ statistically (P = .5).

CONCLUSIONS

Use of aerostatic sheaths trended toward reducing AE events during de novo TDC placement. This trend was not statistically significant, probably owing to the rarity of AE despite the large sample size. Air embolism occurs during OTWE at a rate similar to de novo placement with aerostatic sheaths as well as during tract recanalization.

Risk factors associated with hemodialysis central venous catheter malfunction; a retrospective analysis of a randomized controlled trial

Background

We previously reported a reduction in central venous catheter (CVC) malfunction when using once-weekly recombinant tissue-plasminogen activator (rt-PA) as a locking solution, compared with thrice-weekly heparin.

Objectives

To identify risk factors for CVC malfunction to inform a targeted strategy for rt-PA use.

Design

Retrospective analysis.

Setting

Canadian hemodialysis (HD) units.

Patients

Adults with newly placed tunnelled upper venous system CVCs randomized to a locking solution of rt-PA(1 mg/mL) mid-week and heparin (5000 u/ml) on the other HD sessions, or thrice-weekly heparin (5000 u/ml).

Measurements

CVC malfunction (the primary outcome) was defined as: peak blood flow less than 200 mL/min for thirty minutes during a HD session; mean blood flow less than 250 mL/min for two consecutive HD sessions; inability to initiate HD.

Methods

Cox regression was used to determine the association between patient demographics, HD session CVC-related variables and the outcome of CVC malfunction.

Results

Patient age (62.4 vs 65.4 yr), proportion female sex (35.6 vs 48.4%), and proportion with first catheter ever (60.7 vs 61.3%) were similar between patients with and without CVC malfunction. After multivariate analysis, risk factors for CVC malfunction were mean blood processed < 65 L when compared with ≥ 85 L in the prior 6 HD sessions (HR 4.36; 95% CI, 1.59 to 11.95), and mean blood flow < 300 mL/min, or 300 – 324 mL/min in the prior 6 HD sessions (HR 7.65; 95% CI, 2.78 to 21.01, and HR 5.52; 95% CI, 2.00 to 15.23, respectively) when compared to ≥ 350 mL/min.

Limitations

This pre-specified post-hoc analysis used a definition of CVC malfunction that included blood flow, which may result in an overestimate of the effect size. Generalizability of results to HD units where trisodium citrate locking solution is used may also be limited.

Conclusions

HD session characteristics including mean blood processed and mean blood flow were associated with CVC malfunction, while patient characteristics were not. Whether targeting these patients at greater risk of CVC malfunction with rt-PA as a locking solution improves CVC longevity remains to be determined.

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.

Fibrin sheath and its relation to subsequent events after tunneled dialysis catheter exchange

The use of tunneled catheters (TDC) for chronic hemodialysis is frequent and often fails due to fibrin or thrombus and infection. We hypothesized that the presence of fibrin sheath in TDC increases the risk for subsequent catheter malfunction and infection. We did a retrospective review of TDC exchanges and de novo placements from January 2005 to September 2011. Demographic data, information about the catheter procedure, and radiological data were collected. Final outcome analysis included 168 procedure events. Three groups of catheter procedures were identified: catheter exchange without a fibrin sheath (CE), catheter exchange with a treated fibrin sheath (CEF), and de novo catheter placements (DCP). Fibrin sheath incidence was 47%. In the CEF group, there was no statistical difference in the incidence of subsequent infections or dysfunctions (7% and 60%, respectively), when compared with the CE group (9% and 43%, respectively), (p=0.3). Mean time to subsequent dysfunction or infection was similar for CEF and CE (135 vs. 136 days, p-value, 0.98). Fibrin sheaths are common and should be evaluated when performing TDC exchange. If the fibrin sheath is treated, there is no increased incidence in subsequent catheter dysfunction or infection compared with patients without a fibrin sheath.

Complications of catheters: tunneled and nontunneled

Central venous catheters for hemodialysis remain an indispensable modality of vascular access in the United States. Despite strong recommendations by the NKF-KDOQI guidelines to reduce the dependence on catheters, > 80% of all patients initiate hemodialysis using a central venous catheter. Although the tunneled dialysis catheters have some advantages, their disadvantages are many and often dwarf the miniscule advantages. This review is intended to discuss the complications--both acute and chronic--related to the use of tunneled dialysis catheters for hemodialysis access.

Effect of mechanical brushing on survival and hemodynamic characteristics of tunneled hemodialysis catheters

PURPOSE

Tunneled catheters used for hemodialysis treatment often become dysfunctional due to deposition of clotting material within the catheter lumen. In a retrospective study design we investigated the effect of mechanical brushing of dysfunctional tunneled catheters using a metal guide wire with simultaneous installation of urokinase.

MATERIALS AND METHODS

During a period of 26 months all together 24 different catheters in 21 chronic hemodialysis patients were brushed due to insufficient blood flow or increased arterial or venous line pressures resulting in repeated alarms during dialysis treatments.

RESULTS

Median functional survival after brushing was 45 days with 8 catheters being exchanged (n=5) or rebrushed (n=3) within 10 dialysis sessions (4 weeks). After 2 months all together 13 (54%) catheters were exchanged due to repeated dysfunction and by 3 months functional survival was only about 35%. The catheters needing exchange were characterized by low flow and high arterial line resistance already in the dialysis sessions immediately following the brushing procedure. Median survival of the exchanged catheters was considerably longer (>400 days) as compared to the brushed catheters.

CONCLUSIONS

In conclusion mechanical brushing of dysfunctional tunneled hemodialysis catheters can prolong short term function but only affects long term catheter survival in a minority of the patients.

Balloon Angioplasty for Disruption of Tunneled Dialysis Catheter Fibrin Sheath

Purpose

Management of failing tunneled hemodialysis catheters, sometimes the only vascular access for hemodialysis, presents a difficult problem. In spite of various techniques having been developed, no consensus has been reached about the preferred technique, associated with the longest catheter patency.

Methods

We report disruption of the fibrin sheath covering dysfunctional tunneled hemodialysis catheter by means of angioplasty, followed by over guidewire catheter exchange.

Results

Following the procedure, the catheter placed in the recovered lumen of the vessel presented correct function.

Conclusions

The described procedure allowed maintenance of vascular access in our patient. Additionally, dilatation of the concomitant central vein stenosis opens an option for another attempt for arteriovenous fistula creation.

Difficult central venous access removal: case reports of the use of endovascular snare shearing of endothelialized tetherings

Although a fibrin sheath occurs in most long-standing central venous catheters, they do not typically interfere with complete removal of the catheter. We present 2 cases of long-standing catheters that could not be removed with simple surgical techniques because of endotheliazation via fibrous attachments to the venous wall. Both catheters were successfully removed using a modified snare technique through the right femoral vein.

Feasibility and safety of endovascular stripping of totally implantable venous access devices

PURPOSE

To evaluate the safety and feasibility of percutaneous stripping of totally implantable venous access devices (TIVAD) in case of catheter-related sleeve and to report a technique to free the catheter tip from vessel wall adherence.

MATERIALS AND METHODS

A total of 37 stripping procedures in 35 patients (14 men, 40%, and 21 women, 60%, mean age 53±14 years) were reviewed. Totally implantable venous access devices were implanted because of malignancy in most cases (85.7%). Catheter-related sleeve was confirmed as cause of persistent catheter dysfunction despite instillation of thrombolytics. A technique to mobilize the catheter tip from the vessel wall was used when stripping with the snare catheter was impossible. Technical success, complication rate, and outcome were noted.

RESULTS

A total of 55.9% (n=19) of the 34 technically successful procedures (91.9%) could be done with the snare catheter. In 15 cases (44.1%), additional maneuvers to free the TIVAD's tip from the vessel wall were needed. Success rate was not significantly lower before (72.4%) than after (96.7%) implementation of the new technique (P=0.09). No complications were observed. Follow-up was available in 67.6% of cases. Recurrent catheter dysfunction was found in 17 TIVADs (78.3%) at a mean of 137.7 days and a median of 105 days.

CONCLUSIONS

Stripping of TIVADs is technically feasible and safe, with an overall success rate of 91.9%. Additional endovascular techniques to mobilize the distal catheter tip from the wall of the superior vena cava or right atrium to allow encircling the TIVAD tip with the snare catheter may be needed in 44.1% of cases.

Endovascular Treatment of Dysfunctional Hemodialysis Catheters

Hemodialysis-catheter dysfunction is a common clinical condition in nephrology. Like other central venous devices, hemodialysis-catheters show a disposition for partial or complete thrombotic obstruction and fibrin sleeve formation. Thrombolytic infusion is recommended as therapy of first choice. Alternative interventional strategies include over-the-wire catheter exchange, mechanical fibrin sleeve stripping with a snare and angioplastic sleeve disruption. Those approaches show extremely variable results with mediocre long-term patency rates. Therefore, catheter-avoiding strategies should be considered in detail and AV-fistula creation preferred.

Malfunction of dialysis catheters: management of fibrin sheath and related problems

Suitable central venous access for hemodialysis is frequently required in patients with end-stage renal disease, whenever an arteriovenous fistula or peritoneal dialysis fails or is not a possibility. Ultimately, long-term dialysis via central access may result in dysfunctional catheter with problems such as malpositioning of catheter tip, fibrin sheath formation, thrombosis, infection, and bleeding. The role of interventional radiology is to deliver appropriate treatment to maintain patent and functional access, while minimizing the risk of venous occlusive disease. This article aims at describing different techniques and approaches for management of fibrin sheath associated with malfunctioning tunneled dialysis catheters, as well as to provide scientific evidence from the current literature.

Replacement of inadvertently discontinued tunneled jugular high-flow central catheters with tract recannulation: technical results and outcome

PURPOSE

To determine the technical and clinical outcomes of recannulating the tracts of inadvertently discontinued high-flow tunneled internal jugular central venous catheters.

MATERIALS AND METHODS

Retrospective review was performed of 49 patients who underwent 57 replacements of inadvertently discontinued catheters by recannulation from January 1997 through January 2005. The study group was divided into successful and failed recannulation groups. Technical results were evaluated for duration the catheter had been out, tract age, and laterality (ie, right vs left). Infection rate was calculated by Kaplan-Meier method and the infection rate per 100 catheter days was calculated. Intent-to-treat function rate (including failed recannulations) was calculated by the Kaplan-Meier method.

RESULTS

Seventy percent (n = 40) of discontinued catheters were right-sided and 30% (n = 17) were left-sided. The overall technical success rate was 86% (n = 49). The technical success rates were 100% (n = 10), 89% (32 of 36), and 64% (seven of 11) for catheters that had been outside the body for less than 12 hours, 12-24 hours, and more than 24 hours, respectively. P values for successful versus failed recannulations for tract age, the time the catheter was out, and laterality were .02, .04, and .68, respectively. The infection rate for successful recannulations at 6 months was 24% +/- 9% (0.22 infections per 100 catheter days). Functional catheter rates at 3, 6, 9, and 12 months were 55% +/- 8%, 46% +/- 8%, 29% +/- 10%, and 5% +/- 3%, respectively.

CONCLUSIONS

Recannulating tunneled high-flow jugular catheter tracts has a high technical success rate, particularly when they have fallen out less than 24 hours earlier and have a mature tract. The outcomes of recannulated catheters (ie, infection and function rates) are within the upper limit of results of de novo placement and over-the-wire exchange of catheters in the literature.

Malfunctioning central venous catheters in children: a diagnostic approach

Central venous access is increasingly becoming the domain of the radiologist, both in terms of the insertion of central venous catheters (CVCs) and in the subsequent management of these lines. This article seeks to provide an overview of the CVC types available for paediatric patients and a more detailed explanation of the spectrum of complications that may lead to catheter malfunction. A standard catheter contrast study or 'linogram' technique is described. The normal appearances of such a study and a detailed pictorial review of abnormal catheter studies are provided, together with a brief overview of how information from catheter investigations can guide the management of catheter complications.

The Natural History of Tunneled Hemodialysis Catheters Removed or Exchanged: A Single-Institution Experience

PURPOSE

To track the natural history of tunneled hemodialysis catheters requiring removal or exchange at a single institution.

MATERIALS AND METHODS

Over a 2-year period, tunneled hemodialysis catheters that presented to interventional radiology for removal or exchange were entered into this retrospective study. Patient demographics, catheter location, dwell time, and indication for removal were recorded. Pull-back contrast venography was performed with imaging over the chest. Catheters were then removed or exchanged.

RESULTS

Three hundred thirty-four tunneled dialysis catheters were removed or exchanged in 207 patients; 108 male, median age 53 years. Dwell time, available from 296 catheters, ranged from 1 to 114 days (median, 66 days) for a total of 32,847 catheter days. One hundred three catheters were removed for infection, yielding a rate of infection requiring catheter removal of 3.0 per 1,000 catheter days. One hundred catheters were removed for other working access, and 96 catheters were exchanged for poor function. Two hundred sixty-five were removed or exchanged from the internal jugular vein, 22 from the subclavian vein, and 24 from the femoral vein. One hundred seventy-two (76%) of the 226 catheters studied with contrast had fibrin sheaths; of which 42 had thrombus identified along the catheter tract. One hundred ninety-three catheters were removed, and 141 catheters were exchanged for new catheters with 82 catheters receiving balloon disruption of the fibrin sheath.

CONCLUSIONS

Approximately one third of tunneled dialysis catheters are removed for infection, one third for other working access, and one third for poor function. Catheters usually remain in the patient for a median of 2 months. Fibrin sheaths associated with hemodialysis catheters are very common. Thrombus formation around the sheath is frequent.