A new approach towards extracorporeal gas exchange and first in vitro results

Biomed Tech (Berl). 2023 Nov 7. doi: 10.1515/bmt-2023-0459. Online ahead of print.

Abstract

Objectives: Extracorporeal life support (ECLS) pertains to therapeutic and prophylactic techniques utilized in a wide range of medical applications, with severe pulmonary diseases being the most prominent cases. Over the past decades, little progress has been made in advancing the basic principles and properties of gas exchangers. Here, in an unconventional approach, dialysis hollow fibers are handled with silicone to create a purely diffusive coating that prevents plasma leakage and promotes gas exchange.

Methods: Commercial dialyzers of varying surface area and fiber diameter have been coated with silicone, to determine the impact of each parameter on performance. The impermeability of the silicone layer has been validated by pressurization and imaging methods. SEM images have revealed a homogeneous silicone film coating the lumen of the capillaries, while fluid dynamic investigations have confirmed its purely diffusive nature.

Results: The hemodynamic behavior and the gas exchange efficiency of the silicone-coated prototypes have been investigated in vitro with porcine blood under various operating conditions. Their performance has been found to be similar to that of a commercial PMP oxygenator.

Conclusions: This novel class of gas exchangers is characterized by high versatility and expeditious manufacturing. Intraoperability between conventional ECLS systems and dialysis machines broadens the range of application infinitely. Ultimately, long-term clinical applicability ought to be determined over in vivo animal investigations.

Keywords: diffusion membrane; gas exchange; hemodialysis; hollow fiber oxygenator; polysulfone; silicone.