REDUcing the burden of dialysis Catheter ComplicaTIOns: a National approach (REDUCCTION) - design and baseline results

Replacement Strategies for Tunneled Hemodialysis Catheters with Complications: A Nationwide Cohort Study

Key Points

Background

Tunneled hemodialysis catheters often have infectious or mechanical complications that require unplanned removal and replacement, but the optimal replacement strategy is unknown. This study described the real-world use of two strategies in Australia and compared the survival of replacement catheters inserted by either strategy.

Methods

Observational data from the REDUcing the burden of dialysis Catheter ComplicaTIOns: a National approach trial, which enrolled a nationwide cohort of 6400 adults who received an incident hemodialysis catheter (2016–2020), was used for this secondary analysis. Tunneled catheters were replaced by either catheter exchange through the existing tunnel tract or removal and replacement through a new tract. The effect of the replacement strategy on the time to catheter removal because of infection or dysfunction was estimated by emulating a hypothetical pragmatic randomized trial among a subset of 434 patients with mechanical tunneled catheter failure.

Results

Of 9974 tunneled hemodialysis catheters inserted during the trial, 380 had infectious and 945 had mechanical complications that required replacement. Almost all infected hemodialysis catheters (97%) were removed and separately replaced through a new tunnel tract, whereas nephrology services differed widely in their replacement practices for catheters with mechanical failure (median=50% guidewire exchanged, interquartile range=30%–67%). Service-level differences accounted for 29% of the residual variation after adjusting for patient factors. In the target trial emulation cohort of patients with mechanical catheter failure (n=434 patients), catheter exchange was not associated with lower complication-free survival at 1, 6, or 12 months (counterfactual survival difference at 1 month=5.9%; 95% confidence interval, −2% to 14%).

Conclusions

Guidewire exchange for mechanical failure of catheter was not associated with lower catheter survival and may be preferable for patients.

Trial registration and protocol:

The trial was registered in the Australia and New Zealand clinical trials registry on the June 23, 2016 (ACTRN12616000830493).

Tunneled Hemodialysis Catheter Tip Design and Risk of Catheter Dysfunction: An Australian Nationwide Cohort Study

RATIONALE & OBJECTIVE

Hemodialysis catheter dysfunction is an important problem for patients with kidney failure. The optimal design of the tunneled catheter tip is unknown. This study evaluated the association of catheter tip design with the duration of catheter function.

STUDY DESIGN

Observational cohort study using data from the nationwide REDUCCTION trial.

SETTING & PARTICIPANTS

4,722 adults who each received hemodialysis via 1 or more tunneled central venous catheters in 37 Australian nephrology services from December 2016 to March 2020.

EXPOSURE

Design of tunneled hemodialysis catheter tip, classified as symmetrical, step, or split.

OUTCOME

Time to catheter dysfunction requiring removal due to inadequate dialysis blood flow assessed by the treating clinician.

ANALYTICAL APPROACH

Mixed, 3-level accelerated failure time model, assuming a log-normal survival distribution. Secular trends, the intervention, and baseline differences in service, patient, and catheter factors were included in the adjusted model. In a sensitivity analysis, survival times and proportional hazards were compared among participants' first tunneled catheters.

RESULTS

Among the study group, 355 of 3,871 (9.2%), 262 of 1,888 (13.9%), and 38 of 455 (8.4%) tunneled catheters with symmetrical, step, and split tip designs, respectively, required removal due to dysfunction. Step tip catheters required removal for dysfunction at a rate 53% faster than symmetrical tip catheters (adjusted time ratio, 0.47 [95% CI, 0.33-0.67) and 76% faster than split tip catheters (adjusted time ratio, 0.24 [95% CI, 0.11-0.51) in the adjusted accelerated failure time models. Only symmetrical tip catheters had performance superior to step tip catheters in unadjusted and sensitivity analyses. Split tip catheters were infrequently used and had risks of dysfunction similar to symmetrical tip catheters. The cumulative incidence of other complications requiring catheter removal, routine removal, and death before removal were similar across the 3 tip designs.

LIMITATIONS

Tip design was not randomized.

CONCLUSIONS

Symmetrical and split tip catheters had a lower risk of catheter dysfunction requiring removal than step tip catheters.

FUNDING

Grants from government (Queensland Health, Safer Care Victoria, Medical Research Future Fund, National Health and Medical Research Council, Australia), academic (Monash University), and not-for-profit (ANZDATA Registry, Kidney Health Australia) sources.

TRIAL REGISTRATION

Registered at ANZCTR with study number ACTRN12616000830493.

PLAIN-LANGUAGE SUMMARY

Central venous catheters are widely used to facilitate vascular access for life-sustaining hemodialysis treatments but often fail due to blood clots or other mechanical problems that impede blood flow. A range of adaptations to the design of tunneled hemodialysis catheters have been developed, but it is unclear which designs have the greatest longevity. We analyzed data from an Australian nationwide cohort of patients who received hemodialysis via a tunneled catheter and found that catheters with a step tip design failed more quickly than those with a symmetrical tip. Split tip catheters performed well but were infrequently used and require further study. Use of symmetrical rather than step tip hemodialysis catheters may reduce mechanical failures and unnecessary procedures for patients.

Clinical Adjudication of Hemodialysis Catheter-Related Bloodstream Infections: Findings from the REDUCCTION Trial

Key Points

The inter-rater reliability of reporting hemodialysis catheter-related infectious events between site investigators and trial adjudicators in Australia and New Zealand was substantial. The high concordance level in reporting catheter infections improves confidence in using site-level bacteremia rates as a clinical metric for quality benchmarking and future pragmatic clinical trials. A rigorous adjudication protocol may not be needed if clearly defined criteria to ascertain catheter-associated bacteremia are used.

Background

Hemodialysis catheter-related bloodstream infection (HD-CRBSI) are a significant source of morbidity and mortality among dialysis patients, but benchmarking remains difficult because of varying definitions of HD-CRBSI. This study explored the effect of clinical adjudication process on HD-CRBSI reporting.

Methods

The REDUcing the burden of Catheter ComplicaTIOns: a National approach trial implemented an evidence-based intervention bundle using a stepped-wedge design to reduce HD-CRBSI rates in 37 Australian kidney services. Six New Zealand services participated in an observational capacity. Adult patients with a new hemodialysis catheter between December 2016 and March 2020 were included. HD-CRBSI events reported were compared with the adjudicated outcomes using the end point definition and adjudication processes of the REDUcing the burden of Catheter ComplicaTIOns: a National approach trial. The concordance level was estimated using Gwet agreement coefficient (AC1) adjusted for service-level effects and implementation tranches (Australia only), with the primary outcome being the concordance of confirmed HD-CRBSI.

Results

A total of 744 hemodialysis catheter-related infectious events were reported among 7258 patients, 12,630 catheters, and 1.3 million catheter-exposure days. The majority were confirmed HD-CRBSI, with 77.9% agreement and substantial concordance (AC1=0.77; 95% confidence interval [CI], 0.73 to 0.81). Exit site infections have the highest concordance (AC1=0.85; 95% CI, 0.78 to 0.91); the greatest discordance was in events classified as other (AC1=0.33; 95% CI, 0.16 to 0.49). The concordance of all hemodialysis catheter infectious events remained substantial (AC1=0.80; 95% CI, 0.76 to 0.83) even after adjusting for the intervention tranches in Australia and overall service-level clustering.

Conclusions

There was a substantial level of concordance in overall and service-level reporting of confirmed HD-CRBSI. A standardized end point definition of HD-CRBSI resulted in comparable hemodialysis catheter infection rates in Australian and New Zealand kidney services. Consistent end point definition could enable reliable benchmarking outside clinical trials without the need for independent clinical adjudication.

Low Posterior Internal Jugular Vein Approach for Tunnelled Haemodialysis Catheter Insertion: A Report on Outcomes at a Single Centre

AIM

The impact of technical differences in cannulation technique for tunnelled haemodialysis catheter insertion is undetermined. We aimed to assess clinical outcomes of the low posterior approach for internal jugular vein tunnelled catheter placement.

METHODS

A retrospective audit was undertaken on consecutive tunnelled catheter procedures performed at a single centre between January 2016 and June 2022. Only catheters specifically placed with a low posterior internal jugular approach were included. The study's primary outcome was 12-month catheter survival, evaluated using the Kaplan-Meier survival curve and log-rank test. Secondary outcomes included catheter performance and procedure-related complications.

RESULTS

During the study period, 391 tunnelled internal jugular haemodialysis catheters were inserted in 272 patients using the low posterior technique. The 12-month primary patency rate was 68%. Catheter insertion was successful in 96% of cases. Peri-procedural complications occurred in 4% of cases, most frequently bleeding. The most common reasons for catheter loss were dysfunction (10%) and bacteraemia (6%). The best predictors of catheter failure were advanced age (HR 1.02, 95% CI 1.00-1.04) and in-centre dialysis treatment locality (HR 2.04, 95% CI 1.19-3.45).

CONCLUSION

The low posterior approach for internal jugular vein tunnelled catheter insertion is effective and safe. We demonstrated a 12-month catheter survival rate of 68%. Further research comparing the low posterior approach with other internal jugular vein cannulation techniques is warranted.

Using Cardiohelp, Quadrox, and Nautilus Extracorporeal Membrane Oxygenators as Vascular Access for Hemodialysis, Continuous Renal Replacement Therapy, and Plasmapheresis: A Brief Technical Report

The use of intermittent hemodialysis (iHD), and continuous renal replacement therapy (CRRT), along with extracorporeal membrane oxygenation (ECMO) in patients with acute kidney injury (AKI) and end-stage renal disease (ESRD) is very common. In this technical report, we describe the methods to perform these dialytic therapies safely and effectively using the ECMO circuit in lieu of a separate dialysis catheter. Specifically, we describe in detail how to connect these kidney replacement therapy modalities to a Quadrox, Nautilus, and Cardiohelp HLS (combined oxygenator and pump) oxygenator. The dialysis (iHD or CRRT) inlet is attached to the post-oxygenators Luer-Lock, whereas the return is attached to the pre-oxygenator Luer-Lock, both with a dual lumen pigtail. We also discuss the technical aspects of performing plasmapheresis in conjunction with ECMO and iHD or CRRT. Finally, we highlight the fact that the reported technique does not require modifying the ECMO cannulas/tubing which helps maximize safety.

Effect of a Multifaceted Intervention on the Incidence of Hemodialysis Catheter Dysfunction in a National Stepped-Wedge Cluster Randomized Trial

Introduction

Effective strategies to prevent hemodialysis (HD) catheter dysfunction are lacking and there is wide variation in practice.

Methods

In this post hoc analysis of the REDUcing the burden of dialysis Catheter ComplicaTIOns: a national (REDUCCTION) stepped-wedge cluster randomized trial, encompassing 37 Australian nephrology services, 6361 participants, and 9872 catheters, we investigated whether the trial intervention, which promoted a suite of evidence-based practices for HD catheter insertion and management, reduced the incidence of catheter dysfunction, which is defined by catheter removal due to inadequate dialysis blood flow. We also analyzed outcomes among tunneled cuffed catheters and sources of event variability.

Results

A total of 873 HD catheters were removed because of dysfunction over 1.12 million catheter days. The raw incidence was 0.91 events per 1000 catheter days during the baseline phase and 0.68 events per 1000 catheter days during the intervention phase. The service-wide incidence of catheter dysfunction was 33% lower during the intervention after adjustment for calendar time (incidence rate ratio = 0.67; 95% confidence interval [CI], 0.50-0.89; P = 0.006). Results were consistent among tunneled cuffed catheters (adjusted incidence rate ratio = 0.68; 95% CI, 0.49-0.94), which accounted for 75% of catheters (n = 7403), 97.4% of catheter exposure time and 88.2% of events (n = 770). Among tunneled catheters that survived for 6 months (21.5% of tunneled catheters), between 2% and 5% of the unexplained variation in the number of catheter dysfunction events was attributable to service-level differences, and 18% to 36% was attributable to patient-level differences.

Conclusion

Multifaceted interventions that promote evidence-based catheter care may prevent dysfunction, and patient factors are an important source of variation in events.

A Process Evaluation of the National Implementation of a Bundle for Central Venous Catheter Care for Hemodialysis

Key Points

Health professionals resisted practice change in environments of low infection where the perception of a need to change is small. Standardizing care of central venous catheters for hemodialysis requires breaking down silos of practice to benefit all patients. Knowledge of and adherence to guidelines, formal change management, and ongoing facilitation are required to implement standardized care.

Background

Implementation of a care bundle standardizing insertion, management, and removal practices to reduce infection related to central venous catheters (CVCs) used for hemodialysis was evaluated in a stepped wedge, cluster randomized controlled trial conducted at 37 Australian hospitals providing kidney services, with no reduction in catheter-related blood stream infection detected. This process evaluation explored the barriers, enablers, and unintended consequences of the implementation to explain the trial outcomes.

Methods

Qualitative process evaluation using pre-post semistructured interviews with 38 (19 nursing and 19 medical) and 44 (25 nursing and 19 medical) Australian health professionals involved in hemodialysis CVC management. Analysis was guided by the process implementation domain of the Consolidated Framework for Implementation Research.

Results

Key influences on bundle uptake were that clinicians were open to change that was evidence-based and driven by guidelines and had a desire to improve practice and patient outcomes. However, resistance to change in environments of low infection, working in silos of practice, and a need for individualized delivery of patient education created barriers to uptake. Unintended effects of increased costs and lack of interoperability of systems for data collection were reported. Because the trial was in progress at the time of qualitative data collection, perceptions of the bundle may have been influenced by the fact that practices of participants were being observed as a part of the trial.

Conclusion

This national process evaluation revealed that health professionals who reported experiencing a benefit viewed the bundle positively. Those who already provided most of the recommended care or perceived that their patient population was not included in the research evidence that underpinned the interventions, resisted the implementation of the bundle. Potentially, formal change management processes using facilitation may improve implementation of evidence-based practice.

Clinical Trial registry name and registration number:

Australian New Zealand Clinical Trials Registry, ACTRN12616000830493 .

Multifaceted intervention to reduce haemodialysis catheter related bloodstream infections: REDUCCTION stepped wedge, cluster randomised trial

OBJECTIVE

To identify whether multifaceted interventions, or care bundles, reduce catheter related bloodstream infections (CRBSIs) from central venous catheters used for haemodialysis.

DESIGN

Stepped wedge, cluster randomised design.

SETTING

37 renal services across Australia.

PARTICIPANTS

All adults (age ≥18 years) under the care of a renal service who required insertion of a new haemodialysis catheter.

INTERVENTIONS

After a baseline observational phase, a service-wide, multifaceted intervention bundle that included elements of catheter care (insertion, maintenance, and removal) was implemented at one of three randomly assigned time points (12 at the first time point, 12 at the second, and 13 at the third) between 20 December 2016 and 31 March 2020.

MAIN OUTCOMES MEASURE

The primary endpoint was the rate of CRBSI in the baseline phase compared with intervention phase at the renal service level using the intention-to-treat principle.

RESULTS

1.14 million haemodialysis catheter days of use were monitored across 6364 patients. Patient characteristics were similar across baseline and intervention phases. 315 CRBSIs occurred (158 in the baseline phase and 157 in the intervention phase), with a rate of 0.21 per 1000 days of catheter use in the baseline phase and 0.29 per 1000 days in the intervention phase, giving an incidence rate ratio of 1.37 (95% confidence interval 0.85 to 2.21; P=0.20). This translates to one in 10 patients who undergo dialysis for a year with a catheter experiencing an episode of CRBSI.

CONCLUSIONS

Among patients who require a haemodialysis catheter, the implementation of a multifaceted intervention did not reduce the rate of CRBSI. Multifaceted interventions to prevent CRBSI might not be effective in clinical practice settings.

TRIAL REGISTRATION

Australia New Zealand Clinical Trials Registry ACTRN12616000830493.

The Impact of Clinical Presentation on Survival in Patients Requiring Hemodialysis Catheters for Acute and Unplanned Dialysis: A Prospective Observational Study

BACKGROUND

Most studies addressing hemodialysis initiation with a dialysis catheter focus on patients entering maintenance dialysis programs and exclude other patients, such as those with acute kidney injury (AKI), making interpretation and application of the results difficult for clinicians managing patients at the time of dialysis commencement.

OBJECTIVE

To compare the survival of all patients requiring a catheter for hemodialysis access according to the nature of clinical presentation.

DESIGN

Prospective observational.

SETTING

An Australian tertiary renal unit.

PATIENTS

All patients requiring a central venous catheter (CVC) for hemodialysis access between 2005 and 2015.

MEASUREMENTS

Baseline comorbidities, demographics, and nature of clinical presentation. Data regarding each episode of dialysis access insufficiency and each CVC were collected. The primary outcome was all-cause mortality.

METHODS

Patients were classified into 1 of 3 groups based on physician assessment at the time of presentation: patients believed to have AKI with expected renal recovery (AKI), patients considered to be entering the maintenance dialysis program without a functioning dialysis access (Maintenance Dialysis), patients unable to perform peritoneal dialysis, or use their existing hemodialysis access (Access Failure). Time-split multivariable Cox regression analyses were used to compare survival between groups.

RESULTS

A total of 557 eligible patients had complete prospective data regarding CVC use and were included in the analyses. The majority of patients were in the AKI (246/557, 44%) and Maintenance Dialysis groups (182/557, 33%) compared with the Access Failure group (129/557, 23%). During a median follow-up of 3 years, 302 (54%) of the 557 patients died. Following adjustment, risk of all-cause mortality was higher in the AKI group (hazard ratio [HR]: 2.01, 95% confidence interval [CI]: 1.31-3.60, P = .001) during the first 2 years after catheter insertion and lower in years 2 to 4 (HR: 0.42, 95% CI: 0.20-0.88, P = .02) than in the reference Maintenance Dialysis group. No difference in mortality risk between the Access Failure and reference group was found.

LIMITATIONS

Single-center study. Possible residual confounding owing to the observational study design.

CONCLUSIONS

Patients requiring acute or unplanned hemodialysis experience high mortality, and the nature of clinical presentation does influence outcomes. Most notable is the greater early mortality experienced by patients with AKI compared to other patient groups. Prospective definition of the nature of unplanned dialysis initiation is important to accurately measure and improve outcomes in this high-risk patient population.

HUMAN RESEARCH ETHICS COMMITTEE APPROVAL NUMBER

CH62/6/2017-042.