Abstract: The oxygenater heat exchanger disclosed utilizes a heat transfer tube having several tube legs arranged in closely spaced, parallel relation. A resilient central core fits resiliently within the tube legs and cooperates with spiral ribs on the tube and with the housing to form blood flow spiral passages down around the exterior of each of the tube legs. The blood inlet is positioned to enhance efficient heat exchange.

Abstract: A novel device for mass transfer across a membrane is disclosed, which is particularly suitable for use as a blood oxygenator. The novel device is of the type having a pleated, selectively permeable membrane defining first and second sets of alternating pockets for the flow of a fluid to be treated (e.g. blood) and a treating fluid (e.g. oxygen), and a discrete support screen disposed within each of the pockets of said first and second sets. Of considerable importance is the feature that the support screens are designed to be substantially interdigitated when the assembly of membrane and support screens is held as a compressed stack within the housing of the device. The novel mass transfer apparatus may be utilized as a compact blood oxygenator with excellent gas transfer rates, low pressure drops and negligible trauma to blood components.