Design of an oxygenator with enhanced gas transfer efficiency.

Membrane oxygenator designs were examined with particular attention to the influence of radial and axial flow around windings of microporous polypropylene hollow fibers. Oxygen transfer performance was calculated, employing the Mockros-Leonard modified heat transfer analysis and Curtis-Eberhart normalization methods. Flow through an Avecor Affinity oxygenator was imaged by gamma scintigraphy using a bolus injection of 99mTc-DTPA. Experimental mass transfer correlations were developed for this oxygenator using saline. The oxygen exchange of the Avecor Affinity was slightly less than that for the Medtronic Maxima or COBE Optima models, which are based on similar designs.