Kidney Week

Abstract: FR-OR006

Silicon Nanopore Membrane-Based Implantable Hemodialysis: A Preclinical Proof-of-Concept Study

Session Information

• Advances in Home Dialysis Modalities
  October 26, 2018 | Location: 2, San Diego Convention Center
  Abstract Time: 05:30 PM - 05:42 PM

Category: Bioengineering

• 300 Bioengineering

Authors

• Moyer, Jarrett, UC San Francisco, San Francisco, California, United States

Jarrett Moyer, MD

• Ly, Jimmy, UC San Francisco, San Francisco, California, United States

Jimmy Ly,

• Wright, Nathan, UC San Francisco, San Francisco, California, United States

Nathan Wright,

• Blaha, Charles, UC San Francisco, San Francisco, California, United States

Charles Blaha,

• Fissell, William Henry, Vanderbilt University , Nashville, Tennessee, United States

William Henry Fissell,

• Roy, Shuvo, UC San Francisco, San Francisco, California, United States

Shuvo Roy,

Background

Silicon nanopore membranes (SNM) are highly efficient biomimetic and blood-compatible slit-pore membranes. The high efficiency of the membrane enables hemofiltration and hemodialysis by utilizing cardiovascular perfusion pressure to circulate blood over the filters, enabling the prospect of a fully implanted hemodialysis cartridge. This alternative access strategy could offer a solution for patients with complicated conventional access, and lowers barriers to self-care home hemodialysis.

Methods

A 115 x 57 x 18 mm SNM-based parallel-plate hemodialyzer (SNMHD) was prototyped from polycarbonate and stainless steel. The device was implanted subcutaneously in the neck of a healthy Yucatan mini-pig and anastomosed to the carotid artery and jugular vein via ePTFE vascular grafts. Catheters to supply dialysate were tunneled subcutaneously and attached to the SNMHD. The animal was allowed to recover, and 3-hour hemodialysis sessions were performed on the day of surgery, and post-operative days 1, 2, and 3. Dialysate was recirculated in a counter-current fashion at 10-15 mL/min, and blood flow through the SNMHD was between 1.0-1.5 L/min, assessed by pulse wave Doppler ultrasound. Blood samples were collected at the initiation of dialysis, and dialysate sampled every hour to assess solute clearance over time. The animal was treated with daily aspirin and clopidogrel beginning three days before the implant, continuing throughout the post-operative period.

Results

The animal tolerated surgical implantation and subsequent dialysis sessions without complication. Blood flow through the dialyzer remained brisk throughout the three-day study. All dialysis sessions were completed as planned, via recirculation of normal saline through the dialysate catheters. Over the course of the study, normalized creatinine and urea clearances ranged from 11-42 mL/min/m²and 26-74 mL/min/m², respectively. Albumin concentration in the dialysate remained below the detection limit throughout the study.

Conclusion

We demonstrated preclinical feasibility of an implantable, pumpless SNM-based hemodialyzer. Further development and refinement of the SNMHD could provide an alternative method for hemodialysis access and facilitate frequent in-home dialysis.

Funding

• Other NIH Support