Recommended Clinical Trial End Points for Dialysis Catheters

Vascular Access-Related Distal Ischemia Requiring Intervention: Frequency, Risk Factors, and Consequences

BACKGROUND

Distal ischemia is a rare complication in patients undergoing placement of an arteriovenous (AV) fistula or AV graft. There are limited studies on its frequency, risk factors, clinical consequences, or feasibility of subsequent access.

METHODS

A prospective vascular access database from a large academic medical center was queried retrospectively to identify 1498 patients (mean age 56±15 years, 48% female patients, 73% Black patients) undergoing placement of at least one vascular access from 2011 to 2020. For patients who developed access-related distal ischemia requiring surgical intervention, we determined the frequency of distal ischemia, clinical risk factors, and subsequent outcomes.

RESULTS

Severe access-related distal ischemia occurred in 28 patients (1.9%; 95% confidence interval, 1.3% to 2.7%). The frequency was 0.2% for forearm AV fistulas, 0.9% for upper arm AV fistulas, 2.4% for forearm AV grafts, 2.2% for upper arm AV grafts, and 2.8% for thigh AV grafts. Risk factors independently associated with distal ischemia included female sex (odds ratio [OR], 3.64 [95% confidence interval, 1.52 to 8.72]), peripheral vascular disease (OR, 6.28 [2.84 to 13.87]), and coronary artery disease (OR, 2.37 [1.08 to 5.23]). Surgical interventions included ligation, excision, plication (banding), and other surgical procedures. Five patients developed tissue necrosis. A subsequent AV graft was placed in 13 patients, of whom only one (8%) developed distal ischemia requiring intervention.

CONCLUSIONS

Access-related distal ischemia requiring intervention was rare in this study and more common in women and patients with peripheral vascular disease or coronary artery disease. In some cases, a subsequent vascular access could be placed with a low likelihood of recurrent distal ischemia.

Taurolidine/Heparin Lock Solution and Catheter-Related Bloodstream Infection in Hemodialysis: A Randomized, Double-Blind, Active-Control, Phase 3 Study

BACKGROUND

Catheter-related bloodstream infections (CRBSIs) are one of the most prevalent, fatal, and costly complications of hemodialysis with a central venous catheter (CVC). The LOCK IT-100 trial compared the efficacy and safety of a taurolidine/heparin catheter lock solution that combines taurolidine 13.5 mg/ml and heparin (1000 units/ml) versus heparin in preventing CRBSIs in participants receiving hemodialysis via CVC.

METHODS

LOCK IT-100 was a randomized, double-blind, active-control, multicenter, phase 3 study that enrolled adults with kidney failure undergoing maintenance hemodialysis via CVC from 70 US sites. Participants were randomized 1:1 to taurolidine/heparin catheter lock solution or heparin control catheter lock solution (1000 units/ml). The primary end point was time to CRBSI as assessed by a blinded Clinical Adjudication Committee. Secondary end points were catheter removal for any reason and loss of catheter patency. On the basis of a prespecified interim analysis, the Data and Safety Monitoring Board recommended terminating the trial early for efficacy with no safety concerns.

RESULTS

In the full analysis population ( N =795), nine participants in the taurolidine/heparin arm ( n =397; 2%) and 32 participants in the heparin arm ( n =398; 8%) had a CRBSI. Event rates per 1000 catheter days were 0.13 and 0.46, respectively, with the difference in time to CRBSI being statistically significant, favoring taurolidine/heparin ( P < 0.001). The hazard ratio was 0.29 (95% confidence interval, 0.14 to 0.62), corresponding to a 71% reduction in risk of CRBSIs with taurolidine/heparin versus heparin. There were no significant differences between study arms in time to catheter removal for any reason or loss of catheter patency. The safety of taurolidine/heparin was comparable with that of heparin, and most treatment-emergent adverse events were mild or moderate.

CONCLUSIONS

Taurolidine/heparin reduced the risk of developing a CRBSI in study participants receiving hemodialysis via CVC compared with heparin with a comparable safety profile.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Study Assessing Safety & Effectiveness of a Catheter Lock Solution in Dialysis Patients to Prevent Bloodstream Infection, NCT02651428 .

Predialysis Vascular Access Placement and Catheter Use at Hemodialysis Initiation

BACKGROUND

Current guidelines encourage placement of an arteriovenous (AV) fistula in patients with advanced CKD to avoid initiation of hemodialysis with a central venous catheter. However, the relative merits of predialysis placement of an AV fistula or graft have been poorly studied.

METHODS

This study included 380 patients (mean age 59±14 years, 73% Black patients, 51% male) from a large academic medical center who underwent predialysis placement of an AV fistula (286) or AV graft (94). The study quantified three end points: time from access placement to initiation of dialysis, likelihood of starting hemodialysis without a catheter, and number of vascular access procedures before dialysis initiation.

RESULTS

The eGFR at access surgery was <10, 10-14, and ≥15 ml/min per 1.73 m 2 in 87 (23%), 179 (47%), and 114 (30%) patients, respectively. The median time from access surgery to hemodialysis initiation was 69, 156, and 429 days in patients with an eGFR of <10, 10-14, and ≥15 ml/min per 1.73 m 2 , respectively ( P < 0.001). Hemodialysis was initiated within 2 years of access surgery in 298 (78%) of the patients. Catheter-free hemodialysis initiation was higher in patients with an AV graft versus an AV fistula when the eGFR was <10 ml/min per 1.73 m 2 (88% versus 43%; odds ratio [OR], 9.10 [95% confidence interval, 2.74 to 26.4]) and when the eGFR was 10-14 ml/min per 1.73 m 2 (88% versus 54%; OR, 6.05 [2.35 to 15.0]) but similar when the eGFR was ≥15 ml/min per 1.73 m 2 (90% versus 75%; OR, 3.00 [0.48 to 34.9]). Patients undergoing an AV fistula were more likely to undergo an angioplasty (11% versus 0%, P < 0.001), surgical access revision (26% versus 8%, P < 0.001), a second access placement (16% versus 6%, P = 0.02), and a catheter insertion (32% versus 11%, P < 0.001).

CONCLUSIONS

Among patients with CKD undergoing vascular access surgery when their eGFR was <15 ml/min per 1.73 m 2 , catheter use at dialysis initiation was much less likely when an AV graft, rather than an AV fistula, was placed.

Comparison of Clinical Performance Between Two Types of Symmetric-Tip Hemodialysis Catheters: A Single-Centre, Randomized Trial

PURPOSE

To compare the clinical performance of a newly designed, symmetric-tip Arrow-Clark™ VectorFlow® tunnelled haemodialysis catheter, with a Glidepath™, symmetric-tip tunnelled haemodialysis catheter.

MATERIAL AND METHODS

From November 2018 to October 2020, patients with End-Stage Renal Disease requiring a de novo tunnelled catheter for hemodialysis, were randomized to Vectorflow® (n = 50) or to Glidepath™ catheter (n = 48). The primary outcome was catheter patency at one year following catheter insertion. Catheter failure was defined as the removal of the catheter due to infectious complications, or low blood flow rate by intraluminal thrombosis or fibrin sheath occlusion. Secondary outcomes were blood flow rate, fractional urea clearance and urea reduction ratio during dialysis.

RESULTS

Demographic characteristics were not different between the two groups. At three months and on the one-year endpoint the patency rates with the Vectorflow® catheter were 95.83% and 83.33% respectively, compared to 93.02% at both endpoints with the Glidepath™ catheter (P = 0.27). Catheter failure to infectious complications or low blood flow rate was similar in both groups. Catheter blood flow rate reached the threshold of 300 ml/min at all time points for both catheters. All patients had a high mean fractional urea clearance (1.6-1.7).

CONCLUSIONS

The catheter patency rate was not significantly different in patients with a VectorFlow® or a Glidepath™ catheter. Both catheters presented satisfactory dialysis adequacy over one year.

Validation of a vascular access specific quality of life measure (VASQoL)

BACKGROUND

A self-administered 11 item vascular access specific quality of life measure (VASQoL) was previously derived from detailed qualitative interviews with adult patients with kidney failure who have experienced vascular access using the Capabilities Approach as a theoretical base. This study reports the psychometric validation of the VASQoL measure including its reliability, content validity and responsiveness to change.

METHODS

Cognitive interviews were conducted with 23 adult patients with kidney failure after completion of the VASQoL measure. Focus group discussion with a vascular access professional multidisciplinary team was undertaken (n = 8) and subsequently a further 101 adult kidney failure patients with vascular access (TCVC, AVF or AVG) completed the digital VASQoL measure, EQ-5D and SF-36 questionnaires in a longitudinal study with prospectively recorded vascular access events.

RESULTS

Transcript analysis of cognitive interviews after VASQoL completion indicated that the content was comprehensive and well understood by participants. Assessment of Internal reliability for the VASQoL measure was high (Cronbach's alpha 0.858). Test-retest reliability of the overall VASQoL measure was high (intra class correlation coefficient 0.916). In those patients who experienced a vascular access event, significant differences were observed in paired analysis of the VASQoL physical domain questions and vascular access function domain questions and in the EQ-5D usual activities, pain and anxiety domains. In those with no vascular access event, variation was observed in longitudinal analysis in VASQoL questions relating to worry about VA function and capability domains, whilst no variation was observed in the EQ5D measure.

CONCLUSION

The VASQoL measure has good internal consistency, test-retest reliability, convergent validity and responsiveness to change for clinically relevant vascular access outcomes. This provides a validated, vascular access specific quality of life measure that can be used in future trials of vascular access, evaluation of new technologies and routine use as a patient reported outcome measure (PROM).

Endogenous Panophthalmitis and Eye Enucleation Secondary to Methicillin-Resistant Staphylococcus aureus Bacteremia: A Rare Complication of Tunneled Dialysis Catheter Use

Catheter-related bloodstream infections are among the lethal complications of central venous catheter use. Patients with end-stage kidney disease use tunneled dialysis catheters (TDC) in the absence of arteriovenous access. We report a case of a patient using a TDC who developed panophthalmitis. This patient presented with painful and swollen eyes, fever, and chills. Positive methicillin-resistant Staphylococcus aureus (MRSA) blood cultures were thought to be secondary to a catheter-related bloodstream infection originating from his TDC. A maxillofacial computed tomography scan showed an enlarged, elongated, and proptotic left globe with suspected scleral irregularity suggestive of panophthalmitis. Despite TDC removal and systemic antibiotics, his left eye had to be enucleated. A new TDC was placed after treating the catheter-related bloodstream infection. He continued antibiotic therapy for a total of eight weeks. Panophthalmitis, a rare complication of catheter-related bloodstream infection among hemodialysis patients using a TDC, represents another reason to avoid TDC as hemodialysis access.

Investigation of risk factors for tunneled hemodialysis catheters dysfunction: competing risk analysis of a tertiary center data

BACKGROUND

Hemodialysis tunneled catheters are prone to failure due to infection or thrombosis. Prediction of catheter dysfunction chance and finding the predisposing risk factors might help clinicians to prolong proper catheter function. The multidimensional mechanism of failures following infection or thrombosis needs a multivariable and comprehensive analytic approach.

METHODS

A longitudinal cross-sectional study was implemented on 1048 patients admitted for the first hemodialysis tunneled catheterization attempt between 2013 and 2019 in Shahid Hasheminejdad hospital, Tehran, Iran. Patients' information was extracted from digital and also paper records. Based on their criteria, single and multiple variable analyses were done separately in patients with catheter dysfunction due to thrombosis and infection. T-test and Chi-square test were performed in quantitative and categorical variables, respectively. Competing risk regression was performed under the assumption of proportionality for infection and thrombosis, and the sub-distributional hazard ratios (SHR) were calculated. All statistical inferences were made with a significance level of 0.05.

RESULTS

Four hundred sixty-six patients were enrolled in the analysis based on study criteria. Samples' mean (SD) age was 54(15.54), and 322 (69.1%) patients were female. Three hundred sixty-five catheter dysfunction cases were observed due to thrombosis 123(26.4%) and infection 242(52%). The Median (range) time to catheter dysfunction event was 243(36-1131) days. Single variable analysis showed a statistically significant higher proportion of thrombosis in females (OR = 2.66, 95% CI: 1.77-4.00) and younger patients, respectively. Multivariate competing risk regression showed a statistically significant higher risk of thrombosis in females (Sub-distributional hazard (SHR) = 1.81), hypertensive (SHR = 1.82), and more obese patients (BMI SHR = 1.037). A higher risk of infection was calculated in younger (Age SHR = 0.98) and diabetic (SHR = 1.63) patients using the same method.

CONCLUSION

Female and hypertensive patients are considerably at higher risk of catheter thrombosis, whereas diabetes is the most critical risk factor for infectious catheter dysfunction. Competing risk regression analysis showed a comprehensive result in the assessment of risk factors of catheter dysfunction.

Reduction in hemodialysis catheter-related bloodstream infections after implementation of a novel care program

BACKGROUND

Catheter-related bloodstream infection (CRBSI) due to dialysis is the major factor causing morbidity and mortality factor for patients undergoing hemodialysis and is associated with additional costs for these patients. This study investigated the effect of a novel care program in terms of reducing CRBSIs for hemodialysis patients with nontunneled (temporary) catheters inserted in their femoral veins.

METHODS

This study included dialysis patients (inpatients and outpatients) from July 2018 to September 2019, covering two periods, pre-intervention (baseline period) and intervention with a novel care program (novel care period). The novel care program was initiated on December 1, 2018. The CRBSI rates (/1000 catheter-days) for the baseline and novel care periods were compared, and the characteristics of the pathogens were determined.

FINDINGS

Of a total of 72 patients, 33 were from the baseline period and 39 were from the novel care period. Patients in the baseline and novel care periods had the catheter inserted in their femoral veins for a median of 20 and 29 days, respectively. The CRBSI rate decreased by 82.63%, from 8.52/1000 catheter-days in the baseline period to 1.48/1000 catheter-days in the novel care period (p = 0.036). The most common organisms involved in CRBSIs were coagulase-negative staphylococcus and Burkholderia cepacia (26% for both).

DISCUSSION

The novel care program reduced the incidence of CRBSIs in patients with temporary catheters inserted in their femoral veins.

[Diagnosis and treatment of catheter-related bloodstream infection in hemodialysis: 10 years later]

Patients in hemodialysis on central venous catheter as vascular access are at risk of infections. Catheter-related bloodstream infection is one of the most serious catheter-complications in hemodialysis patients. Its clinical and microbiological diagnosis is challenging. The implementation of empiric antibiotic therapy is based on old recommendations proposing the combination of a molecule targeting methicillin-resistant Staphylococcus aureus and a betalactamin active on P. aeruginosa, and also adapting this probabilistic treatment by carrying out a microbiological register on a local scale, which is rarely done. In our hemodialysis center at Bordeaux University Hospital, an analysis of the microorganisms causing all catheter-related bloodstream infection over the period 2018-2020 enabled us to propose, in agreement with the infectious disease specialists, an adapted probabilistic antibiotic therapy protocol. This approach allowed us to observe a low incidence of meticillinoresistance of Staphylococcus. For catheters inserted more than 6 months ago, we observed no Staphylococcus, no multi-resistant Pseudomonas, and only 2% of Enterobacteria resistant to cephalosporins. A frequent updating of the microbiological epidemiology of catheter-related bloodstream infection, in partnership with the infectious diseases team in each hemodialysis center, allowing an adaptation of the probabilistic antibiotic therapy, and seems to have a good feasibility. This strategy might favor the preservation of microbial ecology on an individual and collective scale in maintenance hemodialysis patients.

Staphylococcus aureus Bacteremia Among Patients Receiving Maintenance Hemodialysis: Trends in Clinical Characteristics and Outcomes

RATIONALE & OBJECTIVE

Staphylococcus aureus (Saureus) bacteremia (SAB) is associated with morbidity and mortality in patients receiving maintenance hemodialysis (HD). We evaluated changes in clinical and bacterial characteristics, and their associations with clinical outcomes with SAB in this population over a 21-year period.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

453 hospitalized, non-neutropenic adults receiving maintenance HD who developed monomicrobial SAB between 1995 and 2015.

EXPOSURE

Clinical characteristics and bacterial genotype.

OUTCOME

All-cause and SAB-attributable mortality, persistent bacteremia, and metastatic complications.

ANALYTICAL APPROACH

Proportions of participants experiencing each outcome were calculated overall and by calendar year. Secular trends were estimated using binomial risk regression, a generalized linear model with the log link function for a binomial outcome. Associations with outcomes were estimated using logistic regression.

RESULTS

Over the 21-year study period, patients receiving maintenance HD experienced significant increases in age- and diabetes-adjusted SAB-attributable mortality (0.45% [95% CI, 0.36%-0.46%] per year), persistent bacteremia (0.86% [95% CI, 0.14%-1.55%] per year), metastatic complications (0.84% [95% CI, 0.11%-1.56%] per year), and infection with the virulent Saureus clone USA300 (1.47% [95% CI, 0.33%-2.52%] per year). Over time, the suspected source of SAB was less likely to be a central venous catheter (-1.32% [95% CI, -2.05 to-0.56%] per year) or arteriovenous graft (-1.08% [95% CI, -1.54 to-0.56] per year), and more likely to be a nonvascular access source (1.89% [95% CI, 1.29%-2.43%] per year). Patients with a nonvascular access suspected source of infection were more likely to die as a result of their S aureus infection (OR, 3.20 [95% CI, 1.36-7.55]). The increase in USA300 infections may have contributed to the observed increase in persistent bacteremia (OR, 2.96 [95% CI, 1.12-7.83]) but did not explain the observed increases in SAB-attributable mortality (OR, 0.83 [95% CI, 0.19-3.61]) or metastatic complications (OR, 1.34 [95% CI, 0.53-3.41]).

LIMITATIONS

Single-center, inpatient cohort.

CONCLUSIONS

The clinical and molecular epidemiology of SAB in patients receiving maintenance HD has changed over time, with an increase in SAB-attributable mortality and morbidity despite a decline in catheter-related infections.

8-hydroxyquinoline-5-(N-4-chlorophenyl) sulfonamide and fluconazole combination as a preventive strategy for Candida biofilm in haemodialysis devices

Introduction. The presence of Candida biofilms in medical devices is a concerning and important clinical issue for haemodialysis patients who require constant use of prosthetic fistulae and catheters.Hypothesis/Gap Statement. This prolonged use increases the risk of candidaemia due to biofilm formation. PH151 and clioquinol are 8-hydroxyquinoline derivatives that have been studied by our group and showed interesting anti-Candida activity.Aim. This study evaluated the biofilm formation capacity of Candida species on polytetrafluoroethylene (PTFE) and polyurethane (PUR) and investigated the synergistic effects between the compounds PH151 and clioquinol and fluconazole, amphotericin B and caspofungin against biofilm cells removed from those materials. Further, the synergistic combination was evaluated in terms of preventing biofilm formation on PTFE and PUR discs.Methodology. Susceptibility testing was performed for planktonic and biofilm cells using the broth microdilution method. The checkerboard method and the time-kill assay were used to evaluate the interactions between antifungal agents. Antibiofilm activity on PTFE and PUR materials was assessed to quantify the prevention of biofilm formation.Results. Candida albicans, Candida glabrata and Candida tropicalis showed ability to form biofilms on both materials. By contrast, Candida parapsilosis did not demonstrate this ability. Synergistic interaction was observed when PH151 was combined with fluconazole in 77.8 % of isolates and this treatment was shown to be concentration- and time-dependent. On the other hand, indifferent interactions were predominantly observed with the other combinations. A reduction in biofilm formation on PUR material of more than 50 % was observed when using PH151 combined with fluconazole.Conclusion. PH151 demonstrated potential as a local treatment for use in a combination therapy approach against Candida biofilm formation on haemodialysis devices.

Major adverse renal events (MARE): a proposal to unify renal endpoints

BACKGROUND

In renal studies, various outcome endpoints are used with variable definitions, making it nearly impossible to perform meta-analyses and deduce meaningful conclusions. Increasing attention is directed towards standardization of renal outcome reporting.

METHODS

A working group was formed to produce a unifying definition of renal outcomes that can be used by all investigators. We propose major adverse renal events (MARE) as the term for a standardized composite of hard renal outcomes. We discuss the components for inclusion in MARE from existing evidence.

RESULTS

MARE could include three to five items, considered relevant to patients and regulators. New onset of kidney injury, that is persistent albuminuria/proteinuria and/or decreasing glomerular filtration rate (GFR) <60 ml/min/1.73 m2, persistent signs of worsening kidney disease, development of end-stage kidney disease with estimated GFR <15 ml/min/1.73 m2 without or with initiation of kidney replacement therapy, and death from renal cause are core items of MARE. Additionally, patient reported outcomes should be reported in parallel to MARE as a standard set of primary (or secondary) endpoints in studies on kidney disease of diabetic, hypertensive-vascular, or other origin.

CONCLUSIONS

MARE as a reporting standard will enhance the ability to compare studies and thus, facilitate meaningful meta-analyses. This will result in standardized endpoints that should result in guideline improvement to better individualize care of patients with kidney disease.

Analysis of pathogenic distribution and drug resistance of catheter-related blood stream infection in hemodialysis patients with vein tunneled cuffed catheter

The catheter related blood stream infections (CRBSI) in hemodialysis (HD) patients with vein tunneled cuffed catheter (TCC) and misuse of antibiotic in clinical practice seriously affected the prognosis of MHD patients. The present study aimed to investigate the pathogen distribution and drug resistance of CRBSI in HD patients with TCC to guide clinical empirical pharmacy. The clinical data of 75 HD patients with TCC diagnosed with CRBSI between January 2011 and March 2015 were retrospectively collected, and the distribution and drug resistance of pathogens were analyzed. In 75 HD patients with TCC diagnosed with CRBSI, there were 33 patients with positive blood culture, and the positive rate of blood culture was 44%. The majority of the 33 pathogens were Gram-positive bacteria (22 strains, accounting for 66.7%). Gram-positive cocci hardly resisted to vancomycin and linezolid, while the resistance rate to penicillin G nearly reached to 100%. Gram-negative bacilli had low resistance rates to carbapenems and quinolone antibiotics, and the resistance rate to cephalosporins antibioticsexceeding 50%. The positive rate of blood culture in 75 HD patients with TCC diagnosed with CRBSI is low. The pathogens resulting in CRBSI in HD patients are mainly Gram-positive bacteria which are significantly resistant to penicillin G, and have a low resistance rate to methicillin. Gram-negative bacteria have high resistance rates to commonly used antibiotics. The pathogen examination should be performed as early as possible and effective antibiotics should be chosen according to drug sensitivity test results in CRBSI in HD patients.

Comparing outcomes of tunnelled dialysis catheter insertions and exchanges with or without fluoroscopy

BACKGROUND/OBJECTIVE

To study the safety and outcome profiles of tunnelled dialysis catheter (TDC) insertions and exchanges with fluoroscopy versus without fluoroscopy.

METHODS

This was a retrospective cohort study of all TDC insertions or exchanges performed at our centre, between January 2017 and December 2017. Patient demographics, laboratory results and catheter placement information were obtained from electronic records. Immediate technical success, early and late catheter associated complications were collected. Outcomes for TDC inserted with or without fluoroscopy were statistically analysed.

RESULTS

A total of 351 TDC insertions and 253 TDC exchanges were performed. Out of 351 TDC insertions, 261 were done with fluoroscopy while 90 were done without. Out of 253 TDC exchanges, 219 were done with fluoroscopy while 34 were done without. For both TDC insertions and exchanges, there were no significant differences in complication rates when done with or without fluoroscopy. Mean duration of catheter patency was longer for TDC inserted without fluoroscopy, after adjusting for site of insertion and presence of previous TDC.

CONCLUSIONS

The technique of inserting TDC in the right internal jugular vein (IJV) without fluoroscopy is a safe and effective method in selected patients. This supports the practice of performing the procedure without fluoroscopy, especially in institutions where fluoroscopy facilities are not readily available. This potentially translates into reduced healthcare resources and hospitalisation days, which is particularly valuable in times of limited resources such as the current Coronavirus Disease 2019 (COVID-19) pandemic.

Unexpected Complication of Central Venous Catheter Exchange: Catheter Fragment Migration

Tunneled central venous catheter (TCVC) placement is often an easy and uncomplicated procedure. As such, some clinicians pay little attention to the procedure, and different complications occurred. Catheter fragment loss in major vessels is a rare but serious complication of in situ catheter exchange with few reported cases in the literature. Once catheter fragments slip into a deep vein, endovascular retrieval should be attempted, due to its high success rate and minimal associated morbidity. A 37-year-old male patient underwent replacement of his temporary catheter with TCVC through a trans-right-internal-jugular-vein approach for maintenance of dialysis. As a major unintended outcome of the operation, a catheter fragment slipped into the right internal jugular vein, then migrated and lodged in the inferior vena cava. We retrieved it with a gooseneck snare without complications. We report the case hoping to emphasize on and raise awareness of the fact that catheter fragment loss is a completely evitable complication, provided the operator follows the correct safety measures and protocols. However, if catheter fragment loss occurred, the fragment should be retrieved as soon as possible. A gooseneck snare is an ideal option for retrieving catheter fragments that have migrated into deep veins.

Opportunities to Improve Antibiotic Prescribing in Outpatient Hemodialysis Facilities: A Report From the American Society of Nephrology and Centers for Disease Control and Prevention Antibiotic Stewardship White Paper Writing Group

Antibiotic use is necessary in the outpatient hemodialysis setting because patients receiving hemodialysis are at increased risk for infections and sepsis. However, inappropriate antibiotic use can lead to adverse drug events, including adverse drug reactions and infections with Clostridioides difficile and antibiotic-resistant bacteria. Optimizing antibiotic use can decrease adverse events and improve infection cure rates and patient outcomes. The American Society of Nephrology and the US Centers for Disease Control and Prevention created the Antibiotic Stewardship in Hemodialysis White Paper Writing Group, comprising experts in antibiotic stewardship, infectious diseases, nephrology, and public health, to highlight strategies that can improve antibiotic prescribing for patients receiving maintenance hemodialysis. Based on existing evidence and the unique patient and clinical setting characteristics, the following strategies for improving antibiotic use are reviewed: expanding infection and sepsis prevention activities, standardizing blood culture collection processes, treating methicillin-susceptible Staphylococcus aureus infections with β-lactams, optimizing communication between nurses and prescribing providers, and improving data sharing across transitions of care. Collaboration among the Centers for Disease Control and Prevention; American Society of Nephrology; other professional societies such as infectious diseases, hospital medicine, and vascular surgery societies; and dialysis provider organizations can improve antibiotic use and the quality of care for patients receiving maintenance hemodialysis.

Challenges and novel therapies for vascular access in haemodialysis

Advances in standards of care have extended the life expectancy of patients with kidney failure. However, options for chronic vascular access for haemodialysis - an essential part of kidney replacement therapy - have remained unchanged for decades. The high morbidity and mortality associated with current vascular access complications highlights an unmet clinical need for novel techniques in vascular access and is driving innovation in vascular access care. The development of devices, biological approaches and novel access techniques has led to new approaches to controlling fistula geometry and manipulating the underlying cellular and molecular pathways of the vascular endothelium, and influencing fistula maturation and formation through the use of external mechanical methods. Innovations in arteriovenous graft materials range from small modifications to the graft lumen to the creation of completely novel bioengineered grafts. Steps have even been taken to create new devices for the treatment of patients with central vein stenosis. However, these emerging therapies face difficult hurdles, and truly creative approaches to vascular access need resources that include well-designed clinical trials, frequent interaction with regulators, interventionalist education and sufficient funding. In addition, the heterogeneity of patients with kidney failure suggests it is unlikely that a 'one-size-fits-all' approach for effective vascular access will be feasible in the current environment.

The diagnostic value of multi-detector CT angiography for catheter-related central venous stenosis in hemodialysis patients

The objective is to compare Multi-detector CT angiography (MDCTA) and digital subtraction angiography (DSA) in diagnosing hemodialysis catheter related-central venous stenosis (CVS). During a period of 6 years, hemodialysis patients with suspected catheter related-CVS who received both MDCTA and DSA were retrospectively enrolled. We analyzed the sensitivity, specificity, accuracy, Cohen's kappa coefficient (κ) and other diagnostic parameters for MDCTA compared to DSA. A total of 1533 vascular segments in 219 patients were analyzed. Among the 280 lesions identified by DSA, 156 were correctly identified by MDCTA. There were 124 false negative and 41 false positive diagnoses. MDCTA had a high specificity (96.73%) but a low sensitivity (55.71%), with a moderate inter-test agreement (κ = 0.5930). In stratified analyses of vascular segments, the specificities of MDCTA were 89.93% (superior vena cava), 98.95% (left brachiocephalic vein), 95.33% (right brachiocephalic vein), 99.53% (left subclavian vein), 97.61% (right subclavian vein), 97.13% (left internal jugular vein), and 95.86% (right internal jugular vein), while the sensitivities were 90.00%, 65.52%, 66.67%, 87.50%, 40.00%, 20.00% and 8.11%, respectively. Good to excellent inter-test agreement was observed for the superior vena cava (κ = 0.7870), left brachiocephalic vein (κ = 0.7300), right brachiocephalic vein (κ = 0.6610), and left subclavian vein (κ = 0.8700) compared with poor to low agreement for the right subclavian vein (κ = 0.3950), left internal jugular vein (κ = 0.1890), and right internal jugular vein (κ = 0.0500). MDCTA had a high specificity in diagnosing hemodialysis catheter related-CVS. Its sensitivity varied by central venous segments, with better performance in superior vena cava and brachiocephalic veins.

Dialysis Access: At the Intersection of Policy, Innovation, and Clinical Care

The Advancing American Kidney Health executive order aims to reduce the incidence of end-stage kidney disease, promote home dialysis therapies, increase the number of kidney transplants, and encourage innovation in new technologies, evidence-based practice, and early detection of kidney disease. Improvements in dialysis access care are essential to the success and expansion of this program, and to being able to provide high-quality, cost-efficient care to this patient population. Specifically, the need for expanded access to home dialysis will require surgeons and interventionalists to become proficient and trained in peritoneal dialysis catheter placement and for the referral process to be streamlined to accommodate the increased interest in this modality. In addition, new technologies, namely percutaneous fistula creation, bioengineered vessels, and a variety of interventions to reduce arteriovenous stenosis, will hopefully allow for timely and durable vascular access options that will support implementation of the executive order.

Hemodialysis Catheters in Infants: A Retrospective Single-Center Cohort Study

PURPOSE

Evaluate technical aspects and outcomes of insertion/maintenance of hemodialysis (HD) central venous catheter (CVC) during infancy.

MATERIALS AND METHODS

Single-center retrospective study of 29 infants who underwent 49 HD-CVC insertions between 2002 and 2016. Demographics, procedural, and post-procedural details, interventional radiology (IR) maintenance procedures, technical modifications, complications, and outcomes were evaluated. Technical adjustments during HD-CVC placement to adapt catheter length to patient size were labeled "modifications." CVCs requiring return visit to IR were called IR-maintenance procedures. Mean age and weight at HD-CVC insertion were 117 days and 4.9 kg.

RESULTS

Of the 29 patients, 13 (45%) required renal-replacement-therapy (RRT) as neonates, 10 (34%) commenced RRT with peritoneal dialysis (PD), and 19 (66%) with HD. Fifteen nontunneled and 34 tunneled HD-CVCs were inserted while patients were ≤1 year. Technical modifications were required placing 25/49 (51%) HD-CVCs: 5/15 (33%) nontunneled and 20/34 (59%) tunneled catheters (P = .08). Patients underwent ≤6 dialysis-cycles/patient during infancy (mean 2.3), and a mean of 4.1 and 49 HD-sessions/catheter for nontunneled and tunneled HD-CVCs, respectively. Mean primary and secondary device service, and total access site intervals for tunneled HD-CVCs were 75, 115, and 201 days, respectively. A total of 26 of 49 (53%) patients required IR-maintenance procedures. Nontunneled lines had greater catheter-related bloodstream infections per 1,000 catheter-days than tunneled HD-CVCs (9.25 vs. 0.85/1,000 catheter days; P = .02). Nineteen patients (65%) survived over 1 year. At final evaluation (December 2017): 8/19 survived transplantation, 5/19 remained on RRT, 2/19 completely recovered, 1/19 lost to follow-up, and 3 died at 1.3, 2, and 10 years.

CONCLUSIONS

Placement/maintenance of HD-CVCs in infants pose specific challenges, requiring insertion modifications, and IR-maintenance procedures to maintain function.

Vascular access in children requiring maintenance haemodialysis: a consensus document by the European Society for Paediatric Nephrology Dialysis Working Group

BACKGROUND

There are three principle forms of vascular access available for the treatment of children with end stage kidney disease (ESKD) by haemodialysis: tunnelled catheters placed in a central vein (central venous lines, CVLs), arteriovenous fistulas (AVF), and arteriovenous grafts (AVG) using prosthetic or biological material. Compared with the adult literature, there are few studies in children to provide evidence based guidelines for optimal vascular access type or its management and outcomes in children with ESKD.

METHODS

The European Society for Paediatric Nephrology Dialysis Working Group (ESPN Dialysis WG) have developed recommendations for the choice of access type, pre-operative evaluation, monitoring, and prevention and management of complications of different access types in children with ESKD.

RESULTS

For adults with ESKD on haemodialysis, the principle of "Fistula First" has been key to changing the attitude to vascular access for haemodialysis. However, data from multiple observational studies and the International Paediatric Haemodialysis Network registry suggest that CVLs are associated with a significantly higher rate of infections and access dysfunction, and need for access replacement. Despite this, AVFs are used in only ∼25% of children on haemodialysis. It is important to provide the right access for the right patient at the right time in their life-course of renal replacement therapy, with an emphasis on venous preservation at all times. While AVFs may not be suitable in the very young or those with an anticipated short dialysis course before transplantation, many paediatric studies have shown that AVFs are superior to CVLs.

CONCLUSIONS

Here we present clinical practice recommendations for AVFs and CVLs in children with ESKD. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system has been used to develop and GRADE the recommendations. In the absence of high quality evidence, the opinion of experts from the ESPN Dialysis WG is provided, but is clearly GRADE-ed as such and must be carefully considered by the treating physician, and adapted to local expertise and individual patient needs as appropriate.

Prevention of Bloodstream Infections in Patients Undergoing Hemodialysis

Bloodstream infections are an important cause of hospitalizations, morbidity, and mortality in patients receiving hemodialysis. Eliminating bloodstream infections in the hemodialysis setting has been the focus of the Centers for Disease Control and Prevention (CDC) Making Dialysis Safer for Patients Coalition and, more recently, the CDC's partnership with the American Society of Nephrology's Nephrologists Transforming Dialysis Safety Initiative. The majority of vascular access-associated bloodstream infections occur in patients dialyzing with central vein catheters. The CDC's core interventions for bloodstream infection prevention are the gold standard for catheter care in the hemodialysis setting and have been proven to be effective in reducing catheter-associated bloodstream infection. However, in the United States hemodialysis catheter-associated bloodstream infections continue to occur at unacceptable rates, possibly because of lapses in adherence to strict aseptic technique, or additional factors not addressed by the CDC's core interventions. There is a clear need for novel prophylactic therapies. This review highlights the recent advances and includes a discussion about the potential limitations and adverse effects associated with each option.

Dialysis catheters in the ICU: selection, insertion and maintenance

PURPOSE OF REVIEW

Choosing the best catheter for renal replacement therapy (RRT) is not an easy task. Beyond catheter length, many of its properties can influence effectiveness of the RRT session. Maintenance between sessions, particularly the locking solution, also impacts catheter lifespan and infection rates.

RECENT FINDINGS

Many innovations in dialysis catheters have been proposed by the industry over the past decade, including the material used, the shape of the lumens and the position of the inflow and outflow holes. Impregnated catheters have also been developed to prevent catheter-related infections. Many locking solutions are available, either for maintaining catheter patency or for preventing infections.

SUMMARY

Although studies conducted in the specific context of the ICU are still scarce, some conclusions can be drawn. Catheter length must be adapted to the insertion site to reach an area of high blood flow. Kidney-shape lumens appear to be less thrombogenic and seem to prevent catheter dysfunction. Catheter tip and lumen holes also affect catheter function. For catheter locking, 4% citrate appears nowadays as one of the best options, but taurolidine-based solutions are also interesting.

Identifying critically important vascular access outcomes for trials in haemodialysis: an international survey with patients, caregivers and health professionals

Background

Vascular access outcomes reported across haemodialysis (HD) trials are numerous, heterogeneous and not always relevant to patients and clinicians. This study aimed to identify critically important vascular access outcomes.

Method

Outcomes derived from a systematic review, multi-disciplinary expert panel and patient input were included in a multilanguage online survey. Participants rated the absolute importance of outcomes using a 9-point Likert scale (7–9 being critically important). The relative importance was determined by a best–worst scale using multinomial logistic regression. Open text responses were analysed thematically.

Results

The survey was completed by 873 participants [224 (26%) patients/caregivers and 649 (74%) health professionals] from 58 countries. Vascular access function was considered the most important outcome (mean score 7.8 for patients and caregivers/8.5 for health professionals, with 85%/95% rating it critically important, and top ranked on best–worst scale), followed by infection (mean 7.4/8.2, 79%/92% rating it critically important, second rank on best–worst scale). Health professionals rated all outcomes of equal or higher importance than patients/caregivers, except for aneurysms. We identified six themes: necessity for HD, applicability across vascular access types, frequency and severity of debilitation, minimizing the risk of hospitalization and death, optimizing technical competence and adherence to best practice and direct impact on appearance and lifestyle.

Conclusions

Vascular access function was the most critically important outcome among patients/caregivers and health professionals. Consistent reporting of this outcome across trials in HD will strengthen their value in supporting vascular access practice and shared decision making in patients requiring HD.

Complications of Hemodialysis Catheter Bloodstream Infections: Impact of Infecting Organism

BACKGROUND

Catheter-related bloodstream infections -(CRBSI) are associated with a high burden of morbidity and mortality, but the impact of infecting organism on clinical outcomes has been poorly studied.

METHODS

This retrospective analysis of a prospective vascular access database from a large academic dialysis center investigated whether the organism type affected the clinical presentation or complications of CRBSI.

RESULTS

Among 339 patients with suspected CRBSI, an alternate source of infection was identified in 50 (15%). Of 289 patients with CRBSI, 249 grew a single organism and 40 were polymicrobial. Fever and/or rigors were presenting signs in ≥90% of patients with Staphylococcus aureus or Gram-negative CRBSI, but only 61% of Staphylococcus epidermidis infections (p < 0.001). Hospitalization occurred in 67% of patients with S. aureus CRBSI versus 34% of those with S. epidermidis and 40% of those with a Gram-negative bacteria (p < 0.001). Admission to the intensive care unit was required in 14, 9, and 2% (p = 0.06); metastatic infection occurred in 10, 4, and 4% (p = 0.42); and median length of stay among patients admitted to the hospital was 4, 4, and 5.5 days (p = 0.60), respectively. Death due to CRBSI occurred in only 1% of patients with CRBSI.

CONCLUSION

CRBSI is confirmed in 85% of catheter-dependent hemodialysis patients in whom it is suspected. S. epidermidis CRBSI tends to present with atypical symptoms. S. aureus CRBSI is more likely to require hospitalization or intensive care admission. Metastatic infection is relatively uncommon, and death due to CRBSI is rare.

Evidence-Based Strategies and Recommendations for Preservation of Central Venous Access in Children

Children with chronic illness often require prolonged or repeated venous access. They remain at high risk for venous catheter-related complications (high-risk patients), which largely derive from elective decisions during catheter insertion and continuing care. These complications result in progressive loss of the venous capital (patent and compliant venous pathways) necessary for delivery of life-preserving therapies. A nonstandardized, episodic, isolated approach to venous care in these high-need, high-cost patients is too often the norm, imposing a disproportionate burden on affected persons and escalating costs. This state-of-the-art review identifies known failure points in the current systems of venous care, details the elements of an individualized plan of care, and emphasizes a patient-centered, multidisciplinary, collaborative, and evidence-based approach to care in these vulnerable populations. These guidelines are intended to enable every practitioner in every practice to deliver better care and better outcomes to these patients through awareness of critical issues, anticipatory attention to meaningful components of care, and appropriate consultation or referral when necessary.

Quantification of Lipoteichoic Acid in Hemodialysis Patients With Central Venous Catheters

Hemodialysis patients with central venous catheters (CVCs) have chronic systemic inflammation, the source of which may be related to intraluminal bacterial biofilm. There is currently no non-invasive method to adequately evaluate intraluminal biofilm. Lipoteichoic acid (LTA) is a Gram-positive bacterial cell wall component that is spontaneously shed. The purpose of this study was to determine whether LTA could be quantified in biological samples and to evaluate potential relationships to markers of inflammation. Heparin-locked catheter aspirate was drawn from both the arterial and venous ports of each CVC prior to dialysis initiation. Venous blood from the dialysis circuit was collected 30 min after dialysis initiation. LTA was quantified in aspirate and plasma. Key markers of inflammation (interleukin-6, and hepcidin) and endothelial dysfunction (soluble vascular endothelial cadherin) were also determined in plasma samples. Catheter aspirate and systemic blood samples were obtained from 40 hemodialysis patients. The median (range) duration of catheter use was 130 (20–1635) days. Unexpectedly, median (range) plasma LTA concentrations (ng/mL) were significantly higher than catheter aspirate LTA concentrations [3.93 (0.25–15) vs. 2.38 (0.1–8.1), respectively, p = 0.01] in the majority (70%) of patients. Area under the receiver operator characteristic (ROC) curve showed good potential prognostic value of catheter aspirate LTA predicting systemic LTA concentrations with an area under the curve of 0.815 (95% CI, 0.68–0.95). A significant correlation was found between LTA and serum ferritin (r = 0.32, p = 0.04), however, there were no significant correlations between LTA and the other inflammation biomarkers assessed. LTA is quantifiable in aspirate and plasma of hemodialysis patients with CVCs and warrants further investigation to determine potential clinical application to intraluminal biofilm evaluation.

Report of the Standardized Outcomes in Nephrology-Hemodialysis (SONG-HD) Consensus Workshop on Establishing a Core Outcome Measure for Hemodialysis Vascular Access

Vascular access outcomes in hemodialysis are critically important for patients and clinicians, but frequently are neither patient relevant nor measured consistently in randomized trials. A Standardized Outcomes in Nephrology-Hemodialysis (SONG-HD) consensus workshop was convened to discuss the development of a core outcome measure for vascular access. 13 patients/caregivers and 46 professionals (clinicians, policy makers, industry representatives, and researchers) attended. Participants advocated for vascular access function to be a core outcome based on the broad applicability of function regardless of access type, involvement of a multidisciplinary team in achieving a functioning access, and the impact of access function on quality of life, survival, and other access-related outcomes. A core outcome measure for vascular access required demonstrable feasibility for implementation across different clinical and trial settings. Participants advocated for a practical and flexible outcome measure with a simple actionable definition. Integrating patients' values and preferences was warranted to enhance the relevance of the measure. Proposed outcome measures for function included "uninterrupted use of the access without the need for interventions" and "ability to receive prescribed dialysis," but not "access blood flow," which was deemed too expensive and unreliable. These recommendations will inform the definition and implementation of a core outcome measure for vascular access function in hemodialysis trials.

FDA Regulatory Perspectives for Studies on Hemodialysis Vascular Access

In an effort to foster innovation and new product development, the American Society of Nephrology and the US Food and Drug Administration partnered to form the Kidney Health Initiative in 2012. Part of the Kidney Health Initiative's mission is to foster development of therapies by creating a collaborative environment where the US Food and Drug Administration and the greater nephrology community can interact to optimize product evaluation. This particular Kidney Health Initiative project focused on products related to hemodialysis vascular access, with the goal of clarifying appropriate trial end points that could subsequently inform clinical, regulatory, and coverage decisions. Both the lack of common definitions and the lack of consensus on trial end points have been viewed as barriers to innovation in this area. Toward this end, the Kidney Health Initiative convened teams of expert stakeholders to address these issues for each major vascular access category (arteriovenous grafts, arteriovenous fistulas, and central venous catheters), and each team provided recommendations. This commentary provides an overview of the US Food and Drug Administration centers that regulate hemodialysis vascular access and certain laws and regulations that affect these products as well as our perspectives on some of the issues raised and end points proposed by the Kidney Health Initiative teams. The standardized definitions and clinical trial end points proposed by the teams represent an important step forward to improve innovation in this area.

Vascular Access Outcomes Reported in Maintenance Hemodialysis Trials: A Systematic Review

BACKGROUND

Many randomized controlled trials have been performed with the goal of improving outcomes related to hemodialysis vascular access. If the reported outcomes are relevant and measured consistently to allow comparison of interventions across trials, such trials can inform decision making. This study aimed to assess the scope and consistency of vascular access outcomes reported in contemporary hemodialysis trials.

STUDY DESIGN

Systematic review.

SETTING & POPULATION

Adults requiring maintenance hemodialysis.

SELECTION CRITERIA

All randomized controlled trials and trial protocols reporting vascular access outcomes identified from ClinicalTrials.gov, Embase, MEDLINE, and the Cochrane Kidney and Transplant Specialized Register from January 2011 to June 2016.

INTERVENTIONS

Any hemodialysis-related intervention.

OUTCOMES

The frequency and characteristics of vascular access outcome measures were analyzed and classified.

RESULTS

From 168 relevant trials, 1,426 access-related outcome measures were extracted and classified into 23 different outcomes. The 3 most common outcomes were function (136 [81%] trials), infection (63 [38%]), and maturation (31 [18%]). Function was measured in 489 different ways, but most frequently reported as "mean access blood flow (mL/min)" (37 [27%] trials) and "number of thromboses" (30 [22%]). Infection was assessed in 136 different ways, with "number of access-related infections" being the most common measure. Maturation was assessed in 44 different ways at 15 different time points and most commonly characterized by vein diameter and blood flow. Patient-reported outcomes, including pain (19 [11%]) and quality of life (5 [3%]), were reported infrequently. Only a minority of trials used previously standardized outcome definitions.

LIMITATIONS

Restricted sampling frame for feasibility and focus on contemporary trials.

CONCLUSIONS

The reporting of access outcomes in hemodialysis trials is very heterogeneous, with limited patient-reported outcomes and infrequent use of standardized outcome measures. Efforts to standardize outcome reporting for vascular access are critical to optimizing the comparability, reliability, and value of trial evidence to improve outcomes for patients requiring hemodialysis.