Toward respiratory support of critically ill COVID-19 patients using repurposed kidney hollow fiber membrane dialysers to oxygenate the blood

The COVID-19 pandemic has highlighted resource constraints in respiratory support. The oxygen transfer characteristics of a hollow fiber membrane dialyser were investigated with a view to repurposing the device as a low-cost, readily available blood oxygenator. Oxygen transfer in a low-flux hollow fiber dialyser with a polysulfone membrane was studied by passing first water and then blood through the dialyser in counter-current to high-purity oxygen. Oxygen transfer rates of about 15% of the nominal 250 ml(STP)/min of a typical adult oxygen consumption rate were achieved for blood flow rates of 500ml/min. Using two such dialysis devices in parallel could provide up to 30% of the nominal oxygen consumption. Specific hollow fiber dialysis devices operating with suitable pumps in a veno-venous access configuration, could provide a cost-effective and readily available supplementation of respiratory support in the face of severe resource constraints.