Pilot Study Assessing Feasibility of a Novel Vascular Access Device in a Rabbit Model
A novel vascular access device was tested in a rabbit model for feasibility. Device enabled consistent arterial access without infection or ischemia. Four-week study showed stable hematologic parameters and device tolerance. Results support potential for direct arteriovenous access in dialysis patients. The arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis; however, it is associated with complications such as failure to mature and aneurysms. Alternatives like arteriovenous grafts (AVGs) and tunneled dialysis catheters (TDCs) have their own issues, including higher rates of thrombosis and infection. A novel vascular access device was developed to facilitate direct arteriovenous hemodialysis access, potentially removing the need for AVFs or AVGs. In this proof-of-concept study, we aim to evaluate the feasibility of our novel vascular access device in a rabbit model and to investigate the effects of repeated arterial cannulation. The device was implanted in a rabbit model around the femoral artery, with twice-weekly blood draws performed over 4 weeks to assess feasibility and effects of repeated cannulation. Postsurgical monitoring focused on identifying complications after device implantation. The device was implanted successfully with minimal surgical time and without complications. Over the 4 weeks, it facilitated easy and reproducible cannulation without infection, ischemia, or hematoma. The rabbit showed stable behavior, normal food intake, and no distress. The distal limb exhibited normal temperature and capillary refill, indicating no blood flow impairment. Complete blood count values remained stable throughout. These results support the device’s feasibility for future studies. The results in this study confirm the feasibility of using a rabbit model for further testing and suggest that repeated arterial cannulation with the novel device may be safe and effective for hemodialysis. Despite a small sample size, the device appears promising for advancing vascular access solutions in hemodialysis.Highlights
Abstract
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Evolution of the novel vascular access device design. (a) Prototype 1: Features a small form factor with a silicone septum for reduced implantation time and patient discomfort. (b) Prototype 2: Revised design to accommodate standard dialysis needles at a 30° insertion angle, simplifying construction by removing the need for a septum. (c) Prototype 3: Current state of the design, refined to ease implantation and reduce concerns of skin erosion.
Schematic of the novel vascular access device. The device is shown split into its 2 components: the upper and lower titanium (6Al-4V) bodies. It features a center channel, an angled funnel-like needle guide, and side wings as tissue anchors. The schematic shows the device with its 30° angle, surrounding a blood vessel, with needle insertion into the entry port for direct vascular access.
Preparation of the surgical field. The area overlying the right femoral artery was shaved and prepped using chlorhexidine, and a sterile field was established with sterile towels and a biopsy drape.
Placement of the bottom piece of the vascular access device. The femoral artery was dissected, identified, and measured to a diameter of 2 mm using blunt and curved hemostats and a surgical retractor. The bottom body of the sterilized novel vascular access device was first positioned underneath the dissected femoral artery.
Completion of the device installment. The top body of the vascular access device was connected to the bottom piece, ensuring that the device surrounded the femoral artery for proper installment.
Securing the device. The vascular access device was closed and secured in place around the femoral artery using titanium screws.
Closure of the surgical incision. The surgical site was closed using a 3-0 Vicryl suture, and the animal was prepared for recovery with a neck cone to prevent self-manipulation of the site.
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