Abstract
Objectives: A novel artificial lung with integrated kidney support is being developed (RenOx) combining oxygenation and hemodialysis fibers utilized outside-in (blood flow outside the fibers). In a previous study, we indicated that 25% of gas exchange fibers in our oxygenator could be replaced by dialysis fibers maintaining sufficient pulmonary support. However, the effect of utilizing dialysis fibers outside-in on renal support is unknown. Thus, this study evaluates the efficiency of commercial dialyzer membranes utilized outside-in compared to traditional inside-out mode regarding solute clearance during continuous renal replacement therapy (CRRT), and ultrafiltration coefficient.
Methods: The performance of commercial dialyzers utilized outside-in and inside-out was compared during in-vitro blood tests adapting the ISO8637:2016. Clearance of urea and creatinine was measured during continuous hemodialysis with a blood flow of 150 mL/min and dialysate flow of 30 mL/min or 50 mL/min, and during continuous hemofiltration with ultrafiltration of 20 mL/min. Filtration efficiency was evaluated in terms of ultrafiltration coefficient.
Results: Clearance of urea and creatinine during continuous hemodialysis and hemofiltration were not significantly different between dialyzers utilized outside-in and inside-out (p >0.2), except for tests with dialysate flow of 50 mL/min, where outside-in fibers achieved higher urea clearance. The ultrafiltration coefficient of dialyzers utilized outside-in (11.7 mL/h/mmHg) was 4 times smaller than the one obtained for inside-out dialyzers. However, required fluid removal could be achieved by managing pressures in the system.
Conclusions: We showed that hemodialyzers utilized outside-in achieved similar small solute clearance dose as traditional dialyzers, sufficient to provide a required CRRT dose of 20–25 mL/kgpatient/h assuming the treatment of a hypothetical 80 kgpatient. Sufficient fluid removal could be provided by controlling system pressures. We consider this a step towards the development of the RenOx device.
Methods: The performance of commercial dialyzers utilized outside-in and inside-out was compared during in-vitro blood tests adapting the ISO8637:2016. Clearance of urea and creatinine was measured during continuous hemodialysis with a blood flow of 150 mL/min and dialysate flow of 30 mL/min or 50 mL/min, and during continuous hemofiltration with ultrafiltration of 20 mL/min. Filtration efficiency was evaluated in terms of ultrafiltration coefficient.
Results: Clearance of urea and creatinine during continuous hemodialysis and hemofiltration were not significantly different between dialyzers utilized outside-in and inside-out (p >0.2), except for tests with dialysate flow of 50 mL/min, where outside-in fibers achieved higher urea clearance. The ultrafiltration coefficient of dialyzers utilized outside-in (11.7 mL/h/mmHg) was 4 times smaller than the one obtained for inside-out dialyzers. However, required fluid removal could be achieved by managing pressures in the system.
Conclusions: We showed that hemodialyzers utilized outside-in achieved similar small solute clearance dose as traditional dialyzers, sufficient to provide a required CRRT dose of 20–25 mL/kgpatient/h assuming the treatment of a hypothetical 80 kgpatient. Sufficient fluid removal could be provided by controlling system pressures. We consider this a step towards the development of the RenOx device.
| Original language | English |
|---|---|
| Article number | 62 |
| Pages (from-to) | 202-202 |
| Number of pages | 1 |
| Journal | Perfusion |
| Volume | 39 |
| Issue number | 1_suppl |
| Publication status | Published - Apr 2024 |