Replacement of failing tunneled hemodialysis catheters through pre-existing subcutaneous tunnels: a comparison of catheter function and infection rates for de novo placements and over-the-wire exchanges

Interventions for treating catheter-related bloodstream infections in people receiving maintenance haemodialysis

BACKGROUND

Patients with kidney failure require vascular access to receive maintenance haemodialysis (HD), which can be achieved by an arteriovenous fistula or a central venous catheter (CVC). CVC use is related to frequent complications such as venous stenosis and infection. Venous stenosis occurs mainly due to trauma caused by the entrance of the catheter into the venous lumen and repeated contact with the vein wall.  A biofilm, a colony of irreversible adherent and self-sufficient micro-organisms embedded in a self-produced matrix of exopolysaccharides, is associated with the development of infections in patients with indwelling catheters. Despite its clinical relevance, the treatment of catheter-related bloodstream infections (CRBSIs) in patients receiving maintenance HD remains controversial, especially regarding catheter management. Antibiotic lock solutions may sterilise the catheter, treat the infection and prevent unnecessary catheter procedures. However, such treatment may also lead to antibiotic resistance or even clinical worsening in certain more virulent pathogens. Catheter removal and delayed replacement may remove the source of infection, improving infectious outcomes, but this approach may also increase vascular access stenosis, thrombosis or both, or even central vein access failure. Catheter guidewire exchange attempts to remove the source of infection while maintaining access to the same vein and, therefore, may improve clinical outcomes and preserve central veins for future access.

OBJECTIVES

To assess the benefits and harms of different interventions for CRBSI treatment in patients receiving maintenance HD through a permanent CVC, such as systemic antibiotics alone or systemic antibiotics combined with either lock solutions or catheter guidewire exchange or catheter replacement.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 21 December 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) and quasi-RCTs evaluating the management of CRBSI in permanent CVCs in people receiving maintenance HD.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, assessed their risk of bias, and performed data extraction. Results were expressed as risk ratios (RR) or hazard ratios (HR) for dichotomous outcomes and mean difference (MD) for continuous outcomes, with their 95% confidence intervals (CI). The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

We identified two RCTs and one quasi-RCT that enrolled 760 participants addressing the treatment of CRBSIs in people (children and adults) receiving maintenance HD through CVC. No two studies compared the same interventions. The quasi-RCT compared two different lock solutions (tissue plasminogen activator (TPA) and heparin) with concurrent systemic antibiotics. One RCT compared systemic antibiotics alone and in association with an ethanol lock solution, and the other compared systemic antibiotics with different catheter management strategies (guidewire exchange versus removal and replacement). The overall certainty of the evidence was downgraded due to the small number of participants, high risk of bias in many domains, especially randomisation, allocation, and other sources of bias, and missing outcome data. It is uncertain whether an ethanol lock solution used with concurrent systemic antibiotics improved CRBSI eradication compared to systemic antibiotics alone (RR 1.61, 95% CI 1.16 to 2.23) because the certainty of this evidence is very low. There were no reported differences between the effects of TPA and heparin lock solutions on cure rates (RR 0.92, 95% CI 0.74 to 1.15) or between catheter guidewire exchange versus catheter removal with delayed replacement, expressed as catheter infection-free survival (HR 0.88, 95% CI 0.43 to 1.79). To date, no results are available comparing other interventions. Outcomes such as venous stenosis and/or thrombosis, antibiotic resistance, death, and adverse events were not reported.

AUTHORS' CONCLUSIONS

Currently, there is no available high certainty evidence to support one treatment over another for CRBSIs. The benefit of using ethanol lock treatment in combination with systemic antibiotics compared to systemic antibiotics alone for CRBSIs in patients receiving maintenance HD remains uncertain due to the very low certainty of the evidence. Hence, further RCTs to identify the benefits and harms of CRBSI treatment options are needed. Future studies should unify CRBSI and cure definitions and improve methodological design.

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.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Shanghai expert consensus on totally implantable access ports 2019

Totally implantable access ports (TIAPs) are used for patients with poor peripheral vascular support requiring central venous access. In recent years, TIAPs have been gradually accepted and promoted by patients, doctors, and nurses owing to their advantages of convenient carrying, a long maintenance period, low complications, and a high quality of life for patients. Currently, medical personnel that handle TIAP implantation and management in China are from different areas of healthcare, including surgery, internal medicine, radiology, nurse anesthesia, vascular access, etc., and many only handle TIAP as a part of their duties. Therefore, the operating procedures and steps for the diagnosis and treatment of complications of TIAP vary from person to person, resulting in different incidence and treatment methods for complications in the implantation and use of TIAP in different medical units. Based on this, we have updated the Shanghai expert consensus on TIAPs from 2015 and explored the diagnosis and treatment procedures of related complications while continuing to emphasize standardized implantation and maintenance.

Effectiveness, safety and cost reduction of long-term tunneled central venous catheter insertion in outpatients performed by an interventional nephrologist

INTRODUCTION

Invasive procedures performed by trained nephrologists can reduce delays in making a definitive vascular access, complications, number of procedures on the same patient, and costs for the Public Health System.

OBJECTIVE

to demonstrate that a long-term tunneled central venous catheter (LTCVC) implanted by a nephrologist is safe, effective, and associated with excellent results.

METHODS

A retrospective study analyzed 149 consecutively performed temporary-to-long-term tunneled central venous catheter conversions in the operating room (OR) from a dialysis facility from March 2014 to September 2017. The data collected consisted of the total procedures performed, demographic characteristics of the study population, rates of success, aborted procedure, failure, complications, and catheter survival, and costs.

RESULTS

the main causes of end stage renal disease (ESRD) were systemic arterial hypertension and diabetes mellitus, 37.9% each. Patients had a high number of previous arteriovenous fistula (1.72 ± 0.84) and temporary catheter (2.87 ± 1.9) attempts until a definitive vascular access was achieved, while the preferred vascular site was right internal jugular vein (80%). Success, abortion, and failure rates were 93.3%, 2.7% and 4%, respectively, with only 5.36% of complications (minors). Overall LTCVC survival rates over 1, 3, 6, and 12 months were 93.38, 71.81, 54.36, and 30.2%, respectively, with a mean of 298 ± 280 days (median 198 days). The procedure cost was around 496 dollars. Catheter dysfunction was the main reason for catheter removal (34%).

CONCLUSION

Our analysis shows that placement of LTCVC by a nephrologist in an OR of a dialysis center is effective, safe, and results in substantial cost savings.

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.

Exchange over the guidewire from non-tunneled to tunneled hemodialysis catheters can be performed without patency loss

PURPOSE

The exchange from a non-tunneled hemodialysis catheter to a tunneled one over a guidewire using a previous venotomy has been reported to be safe. However, some concerns that it may increase infection risk prevent its clinical application. This approach seems particularly useful for acute kidney injury patients requiring initial renal replacement therapy, in whom we frequently worry about the choice of non-tunneled versus tunneled catheters.

MATERIALS AND METHODS

From March 2012 to February 2016, 88 cases to receive the over-the-guidewire exchange method from a non-tunneled to a tunneled catheter and 521 cases to receive de novo tunneled catheter placement from the hemodialysis vascular access cohort were compared retrospectively.

RESULTS

The immediate complication, later catheter dysfunction requiring replacement, and infection rates were comparable between the two groups. Newly placed tunneled catheter survival in the over-the-guidewire exchange group was comparable with survival in the de novo tunneled catheter group (p = 0.24). In addition, when we compared the same two methods among only intensive care unit patients; they remained similar (p = 0.19).

CONCLUSION

An exchange with the over-the-guidewire method from a non-tunneled to a tunneled catheter was comparable to a de novo catheter placement technique. Therefore, this method should be viewed more favorably and should especially be considered for acute kidney injury patients.

Indication for the use of Central Venous Catheters as Vascular Access for Hemodialysis

Adequate treatment for uremic patients on hemodialysis requires valid and lasting access to central vessels.

The Central Venous Catheter (CVC) as a mean of immediate access is indispensable in all acute cases where it has not been possible to prepare an AVF in time and when the peripheral vascularization is highly compromised. We present our investigation on the best access route to central vessels and the selection of the type of catheters to adopt in different conditions.

On the basis of complications arising during the catheter life especially as permanent access, it seems to us that the right internal jugular catheterization with the 2 Tesio catheters Kit is the more useful and less dangerous catheterization.

Salvage Insertion of Tunneled Central Venous Catheters in the Internal Jugular Vein after Accidental Catheter Removal

Purpose

Tunneled catheters are widely used for intermediate to long-term hemodialysis (HD) access, but are prone to several complications that can require catheter replacement. Replacing malfunctioning catheters with a new line, placed in a different access site, can lead to problems with multiple vein occlusions. This has led many nephrologists to continue using the same vein as long as possible by guidewire catheter exchanges, to preserve other veins for future use. We describe a guidewire exchange technique for the Ash-Split catheter in the internal jugular vein.

Methods

In three patients, the exchange was performed because of partial catheter removal, as evidenced by the outward dislocation of the Dacron cuff. In these patients, the guidewire was inserted through the catheter. In two additional patients, the catheter had been completely removed by accident: the replacement of the dislodged tunneled venous catheters was attempted 5 hr and 1 day after accidental removal. In these patients, the guidewire was inserted through the previous tunnel. After guidewire placement, a skin incision was made in the supraclavicular region. The metal guidewire was easily located inside the fibrous structure that had previously surrounded the catheter. The guidewire was then extracted from the subcutaneous tunnel and used to insert a new catheter safely and easily after creating a new tunnel. Patients were routinely given antibiotic prophylaxis (1 g of cefazolin) immediately before the procedure. A strict aseptic technique was used, including several sterile glove changes.

Results

No infections developed following this procedure, which has the potential for bacterial contamination. All procedures were successful. Only in one patient did we have to convert to a different catheter: it was not possible to replace the old Ash-Split catheter with the same dual-lumen catheter because of difficulties in inserting the peel away introducer-catheter complex. In this patient, rather than forcing it with larger dilators or trying to disrupt the fibrin sheath with balloon dilatation, a single lumen Tesio catheter was successfully placed. In both patients who completely lost the previous catheter, the guidewire was readily reinserted through the subcutaneous tunnel into the vein. Catheter function was excellent in all patients, with a test blood flow rate on the 1st catheter use >350 ml/min.

Conclusions

We described a new method for catheter exchange, which allows the easy insertion of a new catheter and the creation of a new and safer subcutaneous tunnel. In addition, we demonstrated that in cases of complete catheter removal, it is possible to reinsert a catheter in the same vein through a guidewire, even when reinsertion was attempted up to 1 day later.

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.

A Modified de novo Insertion Technique for Catheter Replacement in Elderly Hemodialysis Patients: A Single Clinic Retrospective Analysis

Purpose

For patients who rely on a tunneled cuffed catheter, replacement or catheter removal is typically necessary. We recently performed a modified de novo insertion technique for catheter replacement in our practice. As the technique has not yet been studied comprehensively, we performed a retrospective study to evaluate the safety and efficacy of de novo placed catheter without delay for catheter replacement in elderly hemodialysis patients.

Methods

A retrospective review of 164 elderly patients was conducted during a period of three years. There were 84 patients in study group, as well as 80 patients in a control group, who had catheter replacement by guidewire exchange technique. Clinical follow-up data was collected.

Results

All catheters were placed successfully. The mean survival time per catheter was 641 catheter days (study group) and 485 catheter days (control group). The primary patency rates of 30 days were 97.7% (study group) and 90% (control group), respectively, with statistically significant difference (p = 0.04). The incidence of catheter infection was not statistically significantly different in both groups (p = 0.586), but the case of catheter dysfunction was significantly lower in study group compared to control group (p = 0.003).

Conclusions

The de novo placed catheter without delay technique for catheter replacement near the pre-existing venotomy site is safe, and boasts similar infection rates with lower dysfunction rates compared to tunneled catheter insertion by guidewire exchange technique.

Conversion from temporary to tunneled catheters by nephrologists: report of a single-center experience

Background

Nephrologists have increasingly participated in the conversion from temporary catheters (TC) to tunneled-cuffed catheters (TCCs) for hemodialysis.

Objective

To prospectively analyze the outcomes associated with TCC placement by nephrologists with expertise in such procedure, in different time periods at the same center. The impact of vancomycin or cefazolin as prophylactic antibiotics on the infection outcomes was also tested.

Patients and methods

Hemodialysis patients who presented to such procedure were divided into two cohorts: A (from 2004 to 2008) and B (from 2013 to 2015). Time from TC to TCC conversion, prophylactic antibiotics, and reasons for TCC removal were evaluated.

Results

One hundred and thirty patients were included in cohort A and 228 in cohort B. Sex, age, and follow-up time were similar between cohorts. Median time from TC to TCC conversion was longer in cohort A than in cohort B (14 [3; 30] vs 4 [1; 8] days, respectively; P⩽0.0001). Infection leading to catheter removal occurred in 26.4% vs 18.9% of procedures in cohorts A and B, respectively, and infection rate was 0.93 vs 0.73 infections per 1,000 catheter-days, respectively (P=0.092). Infection within 30 days from the procedure occurred in 1.4% of overall cohort. No differences were observed when comparing vancomycin and cefazolin as prophylactic antibiotics on 90-day infection-free TCC survival in a Kaplan–Meier model (log-rank = 0.188). TCC removal for low blood flow occurred in 8.9% of procedures.

Conclusion

Conversion of TC to TCC by nephrologists had overall infection, catheter patency, and complications similar to data reported in the literature. Vancomycin was not superior to cefazolin as a prophylactic antibiotic.

Treatment of Tunneled Dialysis Catheter Malfunction: Revision versus Exchange

Introduction

Exchange procedures involve tunneled dialysis catheter (TDC) removal and exchange over a wire, using the same exit site and venotomy site. Diagnostic imaging or intervention was generally not performed in exchange procedures. Revision procedures involve placement of new TDC using the previous venotomy site and a new tunnel and exit site. The majority of revisions usually include diagnostic imaging and intervention in the central circulation if needed.

Methods

A retrospective single review of 70 patients who underwent 97 TDC replacements from 2010 to early 2012 because of catheter malfunction was evaluated for either infection or malfunction within 30 days of the procedure.

Results

There were 41 exchanges and 56 revisions out of the 97 procedures performed. There were eight infections (documented by positive blood culture) in the exchanges (19.5%) and one in the revision group (1.8%). The need for an additional procedure due to malfunction was 10 in the exchange (24.4%) and 10 (17.8%) in the revision group.

Conclusions

Revision is a clearly superior procedure with regard to infection and more data need to be gathered as to whether it will decrease repeat procedures.

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.

Radiological diagnosis of dialysis-associated complications

In daily clinical practice, the radiologist in the context of diagnosis often faces dialysis-associated complications. The complications are numerous and range from infections, catheter dysfunctions, haematomas, cardiovascular diseases, digital ischaemia, and pseudoaneurysms to shunt stenosis. In this pictorial essay, we take a close look at the imaging diagnostics of the most common complications in dialysis patients. Teaching Points • The occurrence of venous stenosis in haemodialysis patients is up to 41 %. • Catheters usually have a fibrin sheath that can be rinsed but not aspirated. • The steal phenomenon occurs in 75-90 % of patients with a shunt system. • Arterial pseudoaneurysms can cause a number of complications.

Vascular access in therapeutic apheresis: update 2013

This review addresses the types of vascular access available for patients who need therapeutic apheresis (TA). As in hemodialysis, vascular access for TA is chosen based on type of procedure prescribed, the patient's vascular anatomy, the acuity, frequency and duration of treatment, and the underlying disease state. The types of access available include peripheral vein cannulation, central venous catheters: including nontunneled and tunneled catheters, arterio-venous grafts and arterio-venous fistulas. Peripheral veins and central venous catheters are most frequently utilized for the acute administration of TA, and may be used over a period of weeks to months. Arterio-venous grafts and fistulas are not commonly used in TA procedures, but are an option in patients with an anticipated long course of TA, usually for a period of several months or years. The types and frequency of complications associated with various types of vascular access, including: access dysfunction and infections are reviewed, and strategies for their prevention and management are offered.

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.

A single institutional experience of conversion of non-tunneled to tunneled hemodialysis catheters: a comparison to de novo placement

PURPOSE

To compare the outcomes of conversion of non-tunneled to tunneled hemodialysis catheters with de novo placement of tunneled catheters and to determine the effect of time to conversion of non-tunneled to tunneled catheters on the incidence of complications.

MATERIALS AND METHODS

A retrospective data analyses was performed on 1,154 patients who had de novo placement of tunneled hemodialysis catheters (control group) and 254 patients who underwent conversion of non-tunneled to tunneled catheters (study group). The outcomes including technical complications, infection, and catheter dysfunction were compared between the two groups.

RESULTS

The technical success rate was 100 % in both the groups with no complications recorded at the time of procedure or within 24 h of insertion. The most common complication encountered in both the groups was catheter dysfunction (15.6 % in controls and 18.1 % in study). Infection rates/100 catheter days for the control and study groups were 0.17 and 0.19, respectively. Infection-free survival was not statistically different between the two groups. The time spent with non-tunneled catheter prior to conversion did not significantly alter the rates of catheter dysfunction and infection in the study group.

CONCLUSION

The efficacy and safety of conversion of non-tunneled to tunneled hemodialysis catheters are similar to de novo placement with no difference in the rates of technical success, catheter dysfunction, or infection. However, the exchange of non-tunneled to tunneled catheter can help in preservation of veins for future vascular access, which is of vital importance in patients with chronic renal disease.

Imaging and management of complications of central venous catheters

Central venous catheters (CVCs) provide valuable vascular access. Complications associated with the insertion and maintenance of CVCs includes pneumothorax, arterial puncture, arrhythmias, line fracture, malposition, migration, infection, thrombosis, and fibrin sheath formation. Image-guided CVC placement is now standard practice and reduces the risk of complications compared to the blind landmark insertion technique. This review demonstrates the imaging of a range of complications associated with CVCs and discusses their management with catheter salvage techniques.

Case study: first implantation of a frozen, devitalized tissue-engineered vascular graft for urgent hemodialysis access

Previously we reported on the mid- to long-term follow-up in the first clinical trial to use a completely autologous tissue-engineered graft in the high pressure circulation. In these early studies, living grafts were built from autologous fibroblasts and endothelial cells obtained from small skin and vein biopsies. The graft was assembled using a technique called tissue-engineering by self-assembly (TESA), where robust conduits were grown without support from exogenous biomaterials or synthetic scaffolding. One limitation with this earlier work was the long lead times required to build the completely autologous vascular graft. Here we report the first implant of a frozen, devitalized, completely autologous Lifeline™ vascular graft. In a departure from previous studies, the entire fibroblast layer, which provides the mechanical backbone of the graft, was air-dried then stored at -80°C until shortly before implant. Five days prior to implant, the devitalized conduit was rehydrated, and its lumen was seeded with living autologous endothelial cells to provide an antithrombogenic lining. The graft was implanted as an arteriovenous shunt between the brachial artery and the axillary vein in a patient who was dependent upon a semipermanent dialysis catheter placed in the femoral vein. Eight weeks postoperatively, the graft functions without complication. This strategy of preemptive skin and vein biopsy and cold-preserving autologous tissue allows the immediate availability of an autologous arteriovenous fistula, and is an important step forward in our strategy to provide allogeneic tissue-engineered grafts available "off-the-shelf".

Transhepatic hemodialysis catheters: functional outcome and comparison between early and late failure

PURPOSE

To describe the authors' experience with transhepatic placement of catheters, highlighting early and late complications, and to determine if this procedure is a viable option in patients in whom central venous occlusions present a significant challenge.

MATERIALS AND METHODS

The records of all the patients who underwent placement of transhepatic hemodialysis from January 2003 to October 2008 were retrospectively reviewed. Selected patients were dialysis-dependent, having undergone multiple access procedures and revisions. Kaplan-Meier analysis was used to estimate primary and secondary patency.

RESULTS

Twenty-two patients (mean age 42 years, range 22-70 years, 59% women) underwent a total of 127 transhepatic catheter placements at 24 transhepatic access sites; technical success was achieved in all cases. There were no hepatic injuries (bleeding or fistula formation). There were 105 exchanges in 14 patients, with a mean of 7.5 exchanges, a median of 5 exchanges (range 1-18 exchanges), and a catheter migration rate of 0.39 per 100 catheter-days. The sepsis rate was 0.22 per 100 catheter-days, and the catheter thrombosis rate was 0.18 per 100 catheter-days. The mean cumulative catheter duration in situ was 506.2 days, and the mean time catheter in situ was 87.7 days. The mean total access site interval was 1,046 catheter-days (range of 423-1,413 catheter-days).

CONCLUSIONS

Transhepatic hemodialysis catheter placement is associated with low rates of morbidity. In this series, transhepatic catheters provided the possibility of long-term functionality, despite associated high rates of catheter-related maintenance, provides a potentially viable access for patients with exhausted access options.

Usefulness of exchanging a tunneled central venous catheter using a subcutaneous fibrous sheath

OBJECTIVES

The reserve of the venous route to the central veins is important for long-term parenteral nutrition (PN). Frequent catheter-related bloodstream infection (CRBSI) induces occlusion of the venous routes. Therefore, a modified exchange procedure using a tunneled central venous catheter (CVC) with a fibrous sheath was developed to preserve the route to the central veins.

METHODS

Seven patients who required long-term PN received the modified exchange procedure and the outcome of exchanged CVC was retrospectively reviewed.

RESULTS

The procedure was performed 10 times in seven patients. The venous routes were either the subclavicular or the internal jugular vein in all patients. The exchange of the catheter was due to CRBSI or occlusion in almost all patients. The mean duration of new catheter use was 296.2 days following the exchange. Four catheters continued to be used, and the remaining ones were removed. The reasons for removal were severe CRBSI and occlusion, each of which occurred in two catheterized patients, while the reason for removing the remaining catheters was because the patients no longer needed the catheters.

CONCLUSION

The modified catheter exchange using fibrous sheath, even in patients with CRBSI, appears to be an effective procedure for reserving the venous route to the central veins in patients who require either long-term PN or other treatments.

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.

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.

Tunnelled Catheters for the Haemodialysis Patient

Haemodialysis depends upon the establishment of a durable means of vascular access. Although the creation of a successful arterio-venous Fistulae (AVF) is the ideal, this is not always possible or practical. Tunnelled catheters play an important role as an interim/bridge technique for emergency access or while an AVF matures, but may be associated with significant morbidity. The aim of this review is to highlight recent evidence based developments in tunnelled catheters, including methods of placement, complications and possible management strategies.

Conversion of Non-Tunneled to Tunneled Hemodialysis Catheters

PURPOSE

To determine the safety and efficacy of conversion of non-tunneled (temporary) catheters to tunneled catheters in hemodialysis patients.

METHODS

A retrospective review of 112 consecutive conversions in 111 patients was performed over a period of 4 years. Fourteen patients were lost to follow-up. The remaining 97 patients had clinical follow-up. Temporary catheters were converted to tunneled catheters utilizing the same internal jugular venotomy sites and a modified over-the-wire technique with use of a peel-away sheath . Follow-up clinical data were reviewed.

RESULTS

Technical success was achieved in all 112 procedures. None of the 97 patients with follow-up suffered early infection within 30 days. The total number of follow-up catheter days was 13,659 (range 2-790). Cases of confirmed and suspected bacteremia requiring catheter removal occurred at a frequency of 0.10 per 100 catheter days. Suspected catheter infection treated with antibiotics but not requiring catheter intervention occurred at a frequency of 0.04 per 100 catheter days. Frequency of all suspected or confirmed infections was 0.14 per 100 catheter days. Catheter interventions as a result of poor blood flow, inadvertent removal, catheter fracture, or kinking occurred at a rate of 0.18 per 100 catheter days. Life table analysis revealed primary patency rates of 86%, 64%, and 39% at 30 days, 90 days, and 180 days, respectively.

CONCLUSION

Conversion of temporary catheters to tunneled catheters using the pre-existing venotomy sites is safe and has low rates of infection and malfunction. These rates are comparable to previously published rates for tunneled catheters placed de novo and tunneled catheter exchanges.

Avoiding trouble down the line: the management and prevention of hemodialysis catheter-related infections

Over the last 2 decades, hemodialysis catheter use has increased. Annually, approximately 30% of patients using a central venous catheter (CVC) experience a septic or bacteremic episode and are subsequently at risk of its associated long-term complications and mortality. Because of the serious clinical and financial impact of hemodialysis catheter-related bacteremias (HCRIs), standardized, validated definitions based on the hemodialysis patient population are necessary in order to better diagnose, monitor, and report HCRI for patient quality assurance and research purposes. The pathophysiology of HCRI involves a complex interaction between a triad that consists of the host patient, the infecting microorganism, and the vehicle catheter. Although the microorganism contribution in the pathogenesis of HCRI is likely most important, certain patient and catheter-related characteristics may be more amenable to manipulation. The key to managing HCRI is on prophylaxis against the initial microorganism catheter adherence and subsequent biofilm development. General and specific prophylactic maneuvers directed at both an intravascular and extraluminal route of microorganism entry are discussed including antibiotic- and silver-impregnated catheters and dressings, subcutaneous access devices, and topical prophylaxis at the exit site. In addition to systemic antibiotic use, the 3 methods of HRCI treatment using catheter salvage, guidewire exchange, and concurrent antibiotic lock are compared. The outcome and complications of HCRI may be serious and highlight the importance of careful, continual infection surveillance. Although the use of a multidisciplinary hemodialysis infection control team is desirable, staffing education and physician feedback have been shown to improve adherence to infection control guidelines and reduce HCRI.

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

PURPOSE

To compare median patency times after treatment of malfunctioning tunneled hemodialysis catheters by one of three techniques: over-the-wire catheter exchange (CE), fibrin sheath stripping (FSS) from a femoral vein approach, and over-the-wire catheter removal with balloon dilation of fibrin sheath (DFS) followed by catheter replacement with use of the same tract.

MATERIALS AND METHODS

Retrospective study was conducted of 66 consecutive procedures performed over a period of 47 months for poor flow through tunneled hemodialysis catheters despite tissue plasminogen activator infusion trials (CE, n=33; FSS, n=18; DFS, n=15). Baseline parameters (time since initial catheter placement, number of previous catheter interventions, catheter access site, and patient age and sex) were recorded to identify possible pretreatment differences among groups. Outcome comparison was based on duration of adequate catheter function on dialysis during follow-up.

RESULTS

No significant differences in baseline parameters were identified among the three groups (P>.05). Mean follow-up duration (67+/-89 days; range, 0-398 d) was similar among the three groups. The immediate technical success rate was 100%, and there were no complications. Cumulative catheter patency rates were 73% (CE), 72% (FSS), and 65% (DFS) at 1 month; 43% (CE), 60% (FSS), and 39% (DFS) at 3 months; and 28% (CE), 45% (FSS), and 39% (DFS) at 6 months. Median duration of patency was similar among groups (P=.60).

CONCLUSIONS

All three therapies were equivalent in terms of immediate technical success, complication rates, and durability of catheter function during later follow-up. Hence, when one technique is chosen over another, factors other than the period of secondary patency should be considered, such as cost and patient and physician preference.

Is guidewire exchange a better approach for subclavian vein re-catheterization for chronic hemodialysis patients?

BACKGROUND

The objectives of this study were to compare outcomes and survival rates of subclavian vein re-catheterization through guide wire exchange (GWE) or de novo insertion (DN).

MATERIALS AND METHODS

The study was conducted in a retrospective manner. Medical records of 36 patients who received percutaneous subclavian vein re-catheterization for hemodialysis in our institution during the period from April 1, 2001 to September 30, 2004 were reviewed. All patients had at least 2 catheter insertions records in our institute. Incidences of adverse events (infection, thrombosis) were compared between GWE and DN groups using x2 test. Predictors for adverse event occurrences were analyzed using logistic regression models. Cox proportional hazard model was used to investigate the predictors for adverse event-free catheter days. Kaplan-Meire survival curves were computed and compared using log rank test.

RESULTS

Information were generated from 98 catheters (41 from DN, 57 from GWE groups). The average catheter usage was 2.8+/-0.9 devices per patient and the mean catheter-indwelling-day was 125.4+/-129.5 days in this cohort. We found GWE group had significantly lower thrombosis rate (49.1% vs. 85.4% for DN group, P<0.000) in general. Surgical approach was a significant risk factors for catheter thrombosis (GWE vs. DN, odds ratio=0.261, P=0.05). The actuarial survival rates for GWE were > or =30 days, 85.4%; > or =60 days, 75.5%; > or =90 days, 64.5%; > or =180 days, 44.3%. The actuarial survival rates for DN were > or =30 days, 70.7%; > or =60 days, 58.5%; > or =90 days, 34.2%; > or =180 days, 18.4%. GWE group catheters had significantly higher catheter survival rates (P=0.0009). Mahukar catheter (hazard ratio 0.514, P=0.03), non-shock (hazard ratio 3.358, P=0.04), and older age (hazard ratio 0.958, P=0.026) were predictors of adverse event-free remaining catheter days.

CONCLUSION

We suggest that GWE might be a favorable option over DN insertion when revised subclavian vein catheterization is inevitable. GWE can be performed repeatedly without compromising catheter outcomes.

Conversion of Temporary Hemodialysis Catheters to Permanent Hemodialysis Catheters: A Retrospective Study of Catheter Exchange versus Classic de novo Placement

Many clinicians believe that de novo access is required when converting temporary hemodialysis (HD) catheters to long-term or permanent catheters. However, since vascular access sites are at a premium in the dialysis patient, it is important to preserve existing central venous catheters and conserve future access sites. In this retrospective study, data from 94 patients referred to interventional radiology for placement of long-term, tunneled HD catheters between July 2001 and September 2002 were reviewed. The study group consisted of 42 patients in whom the temporary catheter was exchanged for a peel-away sheath and a tunneled catheter inserted using the existing venous access site. The control group included 52 patients who received traditional de novo placement of permanent catheters. Based on available follow-up data, we report a 100% technical success rate, with 72% patency at 30 days in the study group (n = 32; mean age 58 years). By comparison, de novo catheter placement (n = 35; mean age 59 years) yielded a 100% technical success rate, with 83% patency at 30 days. The overall infection rate was 0.30 per 100 catheter-days (total 3036 catheter-days) and 0.36 per 100 catheter-days (total 3295 catheter-days), respectively (chi2 = 0.64, p > or = 0.05). There was no incidence of exit site infection, tunnel infection, or florid sepsis in either group. Likewise, no stenosis or bleeding complication was noted. Thus conversion of a temporary HD catheter to a tunneled catheter using the same venous insertion site is safe, does not increase the risk of infection, and allows conservation of other central venous access sites.

Transhepatic catheter access for hemodialysis

PURPOSE

To retrospectively review the authors' experience regarding the safety and functionality of transhepatic hemodialysis catheters.

MATERIALS AND METHODS

Sixteen patients (seven men and nine women aged 21-77 years; mean age, 51.6 years) underwent placement of 21 transhepatic hemodialysis catheters. Transhepatic catheters were placed in the absence of an available peripheral venous site (11 patients) or for preservation of a single remaining venous site to achieve permanent vascular access. Safety was assessed by means of complications encountered, and catheter functionality was assessed by means of total access site service interval. Catheter patency was described by using a Kaplan-Meier survival curve, and number of catheter days were compared according to patient sex by using a two-sample t test.

RESULTS

Technical success was achieved in all patients. The mean total access site service interval was 138 catheter days (range, 0-599 days), and there was no significant difference according to patient sex (P =.869). Of the 16 catheters placed initially, five became dislodged and required an additional access procedure to be performed. These 21 catheters required 30 exchanges in 10 patients (48%) (range, 1-6 exchanges per patient). The most common reason for catheter exchange was device failure. There were six complications among 21 catheters placed (29%), including one death from massive intraperitoneal hemorrhage on the day after catheter placement.

CONCLUSION

Transhepatic hemodialysis catheters offer a viable option to patients with limited options; however, there are maintenance issues and complications.

Managing the complications of long-term tunneled dialysis catheters

The Kidney Disease Outcomes and Quality Initiative (K/DOQI) guidelines call for a significant increase in the use of natural vein fistulas. Long-term tunneled dialysis catheters (LTTDCs) will have an important role in facilitating the maturation of natural vein fistulas. LTTDCs also functions as the access of last resort in patients who refuse or have exhausted other forms of permanent vascular access. This article, which is based on the authors' experience as interventional nephrologists, discusses factors influencing catheter function. In addition, the article reviews common complications associated with dialysis catheter insertion, including immediate, short-term, and long-term complications. The topics reviewed include stenoses, thrombus formation, fibrin sheath formation, infections, and vascular ingrowth. Suggestions for management are also discussed.

Development of evidence-based protocols for evaluation and management of dysfunctional vascular access devices in interventional radiology

Assessment and treatment of dysfunctional vascular access devices (VADs) is a mutual responsibility of nurses who use these devices and the interventional radiology (IR) team. Understanding causes of dysfunction, implementing assessment and treatment protocols, and communication between referral areas and the IR team are beneficial to both areas and to the patient. This study describes development of evidence-based protocols, combining research utilization and a quality improvement educational process.