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

The pO bottom 2 requires knowledge of the unmeasured gas pressure as it enters the HFMD. The pressure regulator gave a reading of 60kP a but the bulk of this pressure drop would occur at the needle valve that was used to control flow-rate. Also, prior to membrane contact there was a contractor connection and the expansion/elbow entering the membrane unit, whereas on the discharge side there was just the expansion/elbow and a short length of tubing to the discharge. Hence, while it is not possible to exactly know the pressure in the membrane unit, it is safe to assume that it is considerably lower than the regulator's pressure reading. Simple pressure drop calculations suggest that the relevant pressure drop would be as low as 0.1 kP a, but a range of possible pressure scenarios are considered for completeness.