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Temporary Liver Support Using Artificial Lung Technologies: Ammonia Removal via Peritoneal Dialysis for Acute Liver Failure with PFC and PDMS at Vacuum Pressure

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posted on 2023-09-27, 16:16 authored by Lukas DiBeneditto

PURPOSE: This study probes the potential for enhanced ammonia removal in the context of acute liver failure (ALF) management by developing and testing a system incorporating a polydimethylsiloxane (PDMS) filter, perfluorocarbon (PFC), and vacuum pressure. Our hypothesis posits that this system can effectively facilitate ammonia capture and removal in a simulated peritoneal environment. METHODS: Our experimental setup consisted of a system incorporating a PDMS filter, PFCs, and vacuum pressure. We simulated a peritoneal environment using a vortex mixing tank, where we mixed reverse osmosis deionized (RODI) water with different amounts of ammonium hydroxide to replicate the presence of ammonia in ALF. This solution, aided by PFCs, was circulated through the PDMS filter under vacuum pressure, facilitating the diffusion of ammonia from the liquid phase to the gas phase. Sensors measured gas ammonia, liquid ammonium (NH4+), temperature, pressure, pH, mass, and volumetric flow. RESULTS: Our findings indicate that the combination of PFC, the high permeability of the PDMS filter, and vacuum pressure can be used for ammonia gas removal. Further data regarding the efficiency of the PDMS filter will be elaborated in the results section. CONCLUSIONS: Despite certain limitations, such as a limited sample size, limited PDMS filter surface area, and non-medical grade PFC, this study underscores the substantial potential of our proposed system for ALF management. Future studies should aim to refine the peritoneal dialysis model, expand the sample size, increase the PDMS surface area, and introduce animal model testing for further validation. 

History

Date

2023-09-11

Degree Type

  • Master's Thesis

Department

  • Biomedical Engineering

Degree Name

  • Master of Science (MS)

Advisor(s)

Keith Cook, Rosalyn Abbott