Background:

For millions of people worldwide with kidney failure, a well-functioning vascular access, like an arteriovenous fistula (AVF), is essential for life-sustaining hemodialysis. However, the standard method requires puncturing the same AVF with two needles three times a week, which over time can damage the vessel, leading to scarring, narrowing, and frequent failures. These complications often require repeated surgical or minimally invasive procedures (reinterventions), causing significant pain, high medical costs, and exhaustion of the patient's limited blood vessels.

New Approach:

This study will evaluate a modified puncture technique called the Single-Needle Distal Return (SNDR) strategy for long-term AVF care. Instead of using two needles in the AVF, only one needle is placed in the AVF to draw blood. The cleaned blood is then returned to the body through a second needle placed in a superficial vein in the foot or lower leg. This approach aims to reduce trauma to the critical AVF.

Study Plan:

This is a clinical study conducted at the Blood Purification Center of Anhui Medical University Affiliated Suzhou Hospital. We plan to enroll approximately 50 adult hemodialysis patients who use an AVF and are willing to try the SNDR technique. For comparison, we will also observe data from a similar number of patients receiving standard two-needle AVF care during the same period.

The study will last about three years. We will closely monitor patients using the SNDR technique to assess:

Effectiveness: Whether dialysis remains adequate (measured by Kt/V).

Safety: Rates of complications (like bruising or infection), dialysis machine alarms, and venous pressure during treatment.

Practical Benefits: Whether it reduces the need for repair procedures (reinterventions) and hospitalizations related to the AVF.

Economic Impact: Changes in healthcare costs.

Patient Experience: Patient tolerance and comfort with the technique. We will also analyze the characteristics of patients who successfully use this technique long-term to help identify who might benefit most from it in the future.

Potential Significance:

If proven successful and safe for long-term use, the SNDR strategy could help protect a patient's precious AVF, potentially reducing painful procedures, lowering costs, slowing down the exhaustion of blood vessels, and improving the quality of life for people on long-term dialysis. The findings may also guide better planning for vascular access care.

Inclusion Criteria:

• Adult patients (age ≥ 18 years).

Diagnosis of end-stage kidney disease (ESKD) requiring maintenance hemodialysis (three times per week).

Reliable use of a native arteriovenous fistula (AVF) as the primary vascular access for at least the past 3 months.

Willing and able to provide written informed consent to participate in the study.

Adequate superficial venous vasculature in at least one lower extremity (e.g., dorsal foot veins, saphenous tributaries) as assessed by clinical evaluation and/or bedside ultrasound, deemed suitable for cannulation as a venous return site.

For the experimental (SNDR) group: Expressed willingness to adopt the single-needle distal return cannulation strategy.

For the control group: Currently receiving and willing to continue standard two-needle AVF cannulation.

Exclusion Criteria:

• Active systemic infection or localized infection at the potential cannulation sites (AVF or lower extremity veins).

Known severe coagulation disorder or thrombocytopenia (platelet count < 50 × 10⁹/L) that would pose a high risk of bleeding complications from cannulation.

Severe peripheral arterial disease or venous insufficiency in the lower extremities that contraindicates venous cannulation or may compromise limb perfusion.

Unstable cardiovascular status (e.g., uncontrolled heart failure, severe arrhythmias) as determined by the treating nephrologist, which would increase the risk associated with any change in dialysis procedure.

Documented severe cognitive impairment, psychiatric illness, or any condition that would impair the ability to provide informed consent or adhere to the study protocol.

Life expectancy less than 12 months due to non-renal comorbid conditions (e.g., metastatic malignancy).

Currently pregnant or breastfeeding.

Participation in another interventional clinical trial that could confound the outcomes of this study.

Anatomical or pathological condition of the AVF (e.g., extreme depth, aneurysm with overlying skin compromise, complete thrombosis) that precludes safe single-needle cannulation, as judged by the study vascular access team.

Inability to comply with the scheduled study visits and follow-up assessments.