Prospective Analysis of Arteriovenous Access (AVA) Use for Continuous Renal Replacement Therapy (CRRT)

University of North Carolina System

Status: Not yet enrolling

Conditions: End Stage Kidney Disease (ESRD); Continuous Renal Replacement Therapy (CRRT)

Treatments: Other: Cannulation of permanent dialysis access, for the purpose of delivering continuous renal replacement therapy.

Study type: Observational

Funder types: Other

Identifiers

NCT07447128

25-001142.

Details and patient eligibility

About

Arteriovenous fistula or graft are the ideal hemodialysis access. Nonetheless the most common access type used for Continuous Renal Replacement Therapy (CRRT) is either a temporary or permanent hemodialysis catheter. Recommendations for the use of catheters to deliver CRRT in end stage kidney disease (ESKD) patients are lacking on data and subjective to anecdotal experiences and expert consensus. The repetitive placement of catheters in ESKD patients have shown to increase the chances of central vascular stenosis which is one of the main risk factors that lead to access failure. Also, the repetitive use of dialysis catheters increases the risk for catheter associated infections. Dedicated studies demonstrating the safety and feasibility of using arteriovenous access (AVA) for CRRT are scarce. No screening criteria or algorithm exists to determine the adequate patient and clinical scenario to use AVA for CRRT.

Goals of the study:

1. To develop a standard operating procedure for the use of AVA in CRRT.
2. Evaluate the safety and efficacy of using AVA for CRRT.

Full description

This study is a single-center, single-arm, quasi-experimental implementation study incorporating both retrospective and prospective data collection to evaluate the feasibility, safety, and clinical outcomes of using existing arteriovenous access (AVA)-including arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs)-for delivery of continuous renal replacement therapy (CRRT) in critically ill patients.

A. Background and Rationale:The current standard of care for CRRT delivery in the intensive care unit (ICU) is the placement of a temporary dialysis catheter (TDC). While effective, temporary catheter placement is associated with known risks, including catheter-related bloodstream infections, mechanical complications (e.g., pneumothorax, arterial puncture), thrombosis, bleeding, and delays in therapy due to procedural or operator-related factors. These risks may be particularly relevant in patients with end-stage kidney disease (ESKD) who are admitted to the ICU and already possess a mature, functioning AVF or AVG.

Despite the availability of established vascular access in these patients, temporary dialysis catheters are frequently inserted due to concerns regarding vascular safety, needle dislodgement, bleeding risk, access thrombosis in hypotensive states, and limited ICU staff familiarity with AVA cannulation and monitoring. According to the Kidney Disease: Improving Global Outcomes (KDIGO) Acute Kidney Injury guidelines, the recommendation to use a temporary dialysis catheter for CRRT initiation is supported by low-quality evidence (Grade 2D), highlighting the need for further investigation into alternative access strategies.

Retrospective observational studies conducted in the United States, including the "Michigan Experience," have suggested that CRRT delivery via AVA may be safe and feasible when appropriate protocols, interdisciplinary coordination, and patient selection criteria are applied. However, prospective implementation data remain limited.

B. Study Objectives The primary objective of this study is to prospectively evaluate the safety and feasibility of delivering CRRT via pre-existing AVA (AVF or AVG) in ICU patients.

Secondary objectives include:

• Characterization of access-related complications (e.g., needle dislodgement, infiltration, bleeding, thrombosis).
• Assessment of CRRT treatment adequacy and circuit performance.
• Evaluation of therapy interruptions attributable to access-related events.
• Development and refinement of a standardized operating procedure (SOP) for AVA-based CRRT delivery.
• Evaluation of interdisciplinary workflow integration between nephrology, dialysis nursing, and ICU teams.

C. Study Design: This is a single-arm, single-center, quasi-experimental implementation study consisting of:

• Retrospective Phase:Review of prior cases in which AVA was used for CRRT at the institution (if applicable), to inform protocol development and identify baseline complication rates and workflow challenges.
• Prospective Phase:Systematic enrollment of eligible ICU patients with mature AVF or AVG requiring CRRT. All participants will receive CRRT via their existing AVA under a standardized institutional protocol.

A single-arm design was selected to allow focused safety surveillance and protocol optimization without confounding from comparator access modalities. Outcomes will be compared descriptively to historical institutional data for CRRT delivered via temporary dialysis catheters.

D. Patient Selection and Eligibility Considerations:

Patients eligible for inclusion will be critically ill adults requiring CRRT who have a mature, functional AVF or AVG. Careful patient selection is essential to minimize risk. Key clinical considerations include:

• Hemodynamic stability sufficient to support AVA use
• Mental status and sedation plan (to mitigate needle dislodgement risk)
• Anticipated duration of CRRT
• Prior history of vascular access complications
• Availability of appropriately trained nursing staff for access monitoring

Final determination of candidacy will be made by the treating nephrologist in collaboration with the ICU team.

E. Safety Considerations and Monitoring:

Recognized risks of AVA-based CRRT include:

• Needle dislodgement
• Subcutaneous infiltration
• Bleeding
• Access thrombosis, particularly in hypotensive patients
• Delayed recognition of access compromise

To mitigate these risks, a detailed SOP will be implemented, including:

• Standardized cannulation procedures performed by dialysis nurses
• Securement protocols for dialysis needles
• Defined frequency of vascular access site assessments
• Escalation pathways for suspected access complications
• Documentation standards for access monitoring

Dialysis nurses will be responsible for AVA cannulation, needle adjustment, and removal. ICU nurses will manage the CRRT machine and perform continuous monitoring of the vascular access site, with predefined criteria for urgent nephrology notification. Nephrologists will oversee patient selection, duration of AVA use, and overall renal replacement therapy management.

F. Implementation and Interdisciplinary Collaboration:

A central component of this study is the development and iterative refinement of a standardized operating procedure (SOP) to safely integrate AVA-based CRRT into ICU practice. The prospective design allows for real-time safety surveillance, early identification of protocol deviations or unforeseen complications, and structured protocol refinement.

This study represents the first prospective implementation of AVA use for CRRT at this institution and aims to contribute meaningful prospective data to a limited but evolving body of literature. Findings may inform best practices, reduce unnecessary temporary catheter placement, and improve vascular access preservation in patients with ESKD requiring critical care.

Enrollment: 50 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age 18 years or older
• Diagnosis of End-Stage Kidney Disease (ESKD) receiving maintenance chronic hemodialysis
• Admission to the Intensive Care Unit (ICU)
• Presence of a functioning arteriovenous fistula (AVF) or arteriovenous graft (AVG)
• Clinical indication for Continuous Renal Replacement Therapy (CRRT)
• Score of ≥16 points on the study enrollment screening tool

Exclusion criteria

• Age under 18 years
• Arteriovenous access thrombectomy within 30 days prior to study enrollment
• Documented prolonged bleeding from arteriovenous access within 30 days prior to study enrollment
• Current dialysis via temporary or tunneled hemodialysis catheter
• International Normalized Ratio (INR) > 3.0
• Acute liver failure, defined as AST > 1000 U/L and/or ALT > 1000 U/L
• Platelet count < 50,000/µL
• Evidence of disseminated intravascular coagulation (DIC)
• Pregnant patients
• Patients actively attempting to become pregnant

Trial design

50 participants in 1 patient group

Patients with end-stage kidney disease (ESKD) requiring continuous renal replacement therapy (CRRT).

Description:

This cohort will include adult patients with end-stage kidney disease (ESKD) receiving chronic outpatient hemodialysis who are admitted to the Intensive Care Unit (ICU) and require continuous renal replacement therapy (CRRT). Eligible participants must have a mature, functional permanent vascular access used for outpatient hemodialysis, defined as either a functioning arteriovenous fistula (AVF) or a functioning arteriovenous graft (AVG). Patients must meet the inclusion and exclusion criteria prior to enrollment.

Treatment:

Other: Cannulation of permanent dialysis access, for the purpose of delivering continuous renal replacement therapy.