Comparative effectiveness of an individualized model of hemodialysis vs conventional hemodialysis: a study protocol for a multicenter randomized controlled trial (the TwoPlus trial).

BACKGROUND: Most patients starting chronic in-center hemodialysis (HD) receive conventional hemodialysis (CHD) with three sessions per week targeting specific biochemical clearance. Observational studies suggest that patients with residual kidney function can safely be treated with incremental prescriptions of HD, starting with less frequent sessions and later adjusting to thrice-weekly HD. This trial aims to show objectively that clinically matched incremental HD (CMIHD) is non-inferior to CHD in eligible patients. METHODS: An unblinded, parallel-group, randomized controlled trial will be conducted across diverse healthcare systems and dialysis organizations in the USA. Adult patients initiating chronic hemodialysis (HD) at participating centers will be screened. Eligibility criteria include receipt of fewer than 18 treatments of HD and residual kidney function defined as kidney urea clearance ≥3.5 mL/min/1.73 m2 and urine output ≥500 mL/24 h. The 1:1 randomization, stratified by site and dialysis vascular access type, assigns patients to either CMIHD (intervention group) or CHD (control group). The CMIHD group will be treated with twice-weekly HD and adjuvant pharmacologic therapy (i.e., oral loop diuretics, sodium bicarbonate, and potassium binders). The CHD group will receive thrice-weekly HD according to usual care. Throughout the study, patients undergo timed urine collection and fill out questionnaires. CMIHD will progress to thrice-weekly HD based on clinical manifestations or changes in residual kidney function. Caregivers of enrolled patients are invited to complete semi-annual questionnaires. The primary outcome is a composite of patients' all-cause death, hospitalizations, or emergency department visits at 2 years. Secondary outcomes include patient- and caregiver-reported outcomes. We aim to enroll 350 patients, which provides ≥85% power to detect an incidence rate ratio (IRR) of 0.9 between CMIHD and CHD with an IRR non-inferiority of 1.20 (α = 0.025, one-tailed test, 20% dropout rate, average of 2.06 years of HD per patient participant), and 150 caregiver participants (of enrolled patients). DISCUSSION: Our proposal challenges the status quo of HD care delivery. Our overarching hypothesis posits that CMIHD is non-inferior to CHD. If successful, the results will positively impact one of the highest-burdened patient populations and their caregivers. TRIAL REGISTRATION: Clinicaltrials.gov NCT05828823. Registered on 25 April 2023.

Pros and cons of catheter lock solutions.

PURPOSE OF REVIEW: Catheter-related bacteremia (CRB) and catheter dysfunction are major sources of morbidity and mortality when central venous catheters are used as long-term vascular access in hemodialysis patients. Attempts have been made to minimize these complications by the prophylactic use of catheter locking solutions. This review aims to describe the recent advances in the field of lock solutions and to discuss the benefits and risks associated with the routine use of antimicrobial and/or antithrombotic lock solutions. RECENT FINDINGS: Antithrombotic lock solutions may improve patency and CRB but may be cost-prohibitive. Antimicrobial lock solutions may decrease the incidence of CRB, but their routine use is concerning for the risk of systemic toxicity and the development of resistant organisms. Preliminary results suggest a novel antimicrobial and antithrombotic lock solution may be promising in maintaining patency, while decreasing catheter-related bacteremia. SUMMARY: The ideal catheter lock solution would be one that prevents infections and thrombosis safely and effectively, while being economically viable. Recent developments have led to improvements in the development of catheter locking solutions, but the search for the perfect 'solution' is still ongoing.

Hemodialysis Arteriovenous Access Cosmesis Scale (AVACS): A new measure for vascular access.

RATIONALE AND OBJECTIVE: This study aimed to develop a cosmesis scale to evaluate the cosmetic appearance of hemodialysis (HD) arteriovenous (AV) accesses from the perspective of the patient and clinician, which could be incorporated into clinical trials. STUDY DESIGN: Using a modified Delphi process, two AV access cosmesis scale (AVACS) components were developed in a four-round Delphi panel consisting of two surveys and two consensus meetings with two rounds of patient consultation. SETTING AND PARTICIPANTS: The Delphi panel consisted of 15 voting members including five interventional or general nephrologists, five vascular surgeons, three interventional radiologists, and two vascular access nurse coordinators. Four patients experienced with vascular access were involved in patient question development. ANALYTICAL APPROACH: For a component to be included in the AVACS, it had to meet the prespecified panel consensus agreement of ⩾70%. RESULTS: The clinician component of the AVACS includes nine questions on the following AV access features: scarring, skin discoloration, aneurysm/pseudoaneurysms and megafistula appearance. The patient component includes six questions about future vascular access decisions, interference with work or leisure activities, clothing choices, self-consciousness or attractiveness, emotional impact, and overall appearance. LIMITATIONS: Delphi panel methods are subjective by design, but with expert clinical opinion are used to develop classification systems and outcome measures. The developed scale requires further validation testing but is available for clinical trial use. CONCLUSIONS: While safety and efficacy are the primary concerns when evaluating AV access for HD, cosmesis is an important component of the ESKD patient experience. The AVACS has been designed to assess this important domain; it can be used to facilitate patient care and education about vascular access choice and maintenance. AVACS can also be used to inform future research on developing new techniques for AV access creation and maintenance, particularly as relates to AV access cosmesis.

Buttonhole Cannulation of Arteriovenous Fistulas in the United States.

The cannulation technique of a hemodialysis vascular access has remained controversial with differing viewpoints. The quality of dialysis, overall patient safety, and individual dialysis experience often dictate the type of cannulation technique used in clinical practice. The three commonly used techniques to access a hemodialysis vascular access are the rope ladder, area, and buttonhole. Although the buttonhole technique has been around since the mid-1970s, the dialysis community remains divided on its suitability for routine use to provide maintenance hemodialysis therapy. The proponents of this technique value the ease of cannulation with less pain and discomfort whereas the opponents highlight the increased risk of infection. The actual clinical evidence from the United States is limited and remains inconclusive. The current review provides an overview of the available experience from the United States, highlighting the correct technique of creating a buttonhole, summarizing the current evidence, and recommending a need for larger randomized controlled studies in both in-center and home hemodialysis populations.

Definitions and End Points for Interventional Studies for Arteriovenous Dialysis Access.

This paper is part of the Clinical Trial Endpoints for Dialysis Vascular Access Project of the American Society of Nephrology Kidney Health Initiative. The purpose of this project is to promote research in vascular access by clarifying trial end points which would be best suited to inform decisions in those situations in which supportive clinical data are required. The focus of a portion of the project is directed toward arteriovenous access. There is a potential for interventional studies to be directed toward any of the events that may be associated with an arteriovenous access' evolution throughout its life cycle, which has been divided into five distinct phases. Each one of these has the potential for relatively unique problems. The first three of these correspond to three distinct stages of arteriovenous access development, each one of which has been characterized by objective direct and/or indirect criteria. These are characterized as: stage 1-patent arteriovenous access, stage 2-physiologically mature arteriovenous access, and stage 3-clinically functional arteriovenous access. Once the requirements of a stage 3-clinically functional arteriovenous access have been met, the fourth phase of its life cycle begins. This is the phase of sustained clinical use from which the arteriovenous access may move back and forth between it and the fifth phase, dysfunction. From this phase of its life cycle, the arteriovenous access requires a maintenance procedure to preserve or restore sustained clinical use. Using these definitions, clinical trial end points appropriate to the various phases that characterize the evolution of the arteriovenous access life cycle have been identified. It is anticipated that by using these definitions and potential end points, clinical trials can be designed that more closely correlate with the goals of the intervention and provide appropriate supportive data for clinical, regulatory, and coverage decisions.

Lower Extremity Permanent Dialysis Vascular Access.

Hemodialysis remains the most commonly used RRT option around the world. Technological advances, superior access to care, and better quality of care have led to overall improvement in survival of patients on long-term hemodialysis. Maintaining a functioning upper extremity vascular access for a prolonged duration continues to remain a challenge for dialysis providers. Frequently encountered difficulties in clinical practice include (1) a high incidence of central venous catheter-related central vein stenosis and (2) limited options for creating a functioning upper extremity permanent arteriovenous access. Lack of surgical skills, fear of complications, and limited involvement of the treating nephrologists in the decision-making process are some of the reasons why lower extremity permanent dialysis access remains an infrequently used option. Similar to upper extremity vascular access options, lower extremity arteriovenous fistula remains a preferred access over arteriovenous synthetic graft. The use of femoral tunneled catheter as a long-term access should be avoided as far as possible, especially with the availability of newer graft-catheter hybrid devices. Our review provides a summary of clinical evidence published in surgical, radiology, and nephrology literature highlighting the pros and cons of different types of lower extremity permanent dialysis access.