Oxygen transfer characteristics of a hollow fiber dialyser: toward possible repurposing of dialysers as blood oxygenators in the context of constrained availability of respiratory support

David M Rubin; Neil T Stacey; Tonderayi Matambo; Diane Hildebrandt

For a particular rate of flux of oxygen between two transport media, we can use this equation to determine the minimum mass transfer coe cient â—Š area that would be required to achieve the necessary oxygen transfer. To rigorously model a membrane unit, one would ordinarily need to solve this equation along with the respective mass balances for each stream. However, this system presents a simplified problem in two respects; first, the oxygen transport capacity of blood resides primarily in haemoglobin, which reaches saturation at a low partial pressure of oxygen. Hence, neglecting the small amount of dissolved oxygen, essentially all oxygen transfer into blood takes place within a narrow range of partial pressures. Secondly, if pure oxygen is used as the oxygenation medium, then the blood's dissolved oxygen concentration and hence, partial pressure, may be regarded as essentially constant.