Abstract: Processes are disclosed for coating the exteriors of a plurality of hollow fibers which are suitable for fluid separations and which are assembled in the form of a bundle. The processes involve immersing the bundle of hollow fibers in a coating liquid containing material suitable for forming the coating and a substantial amount of solvent. A pressure drop from the exteriors to the interiors of the hollow fibers is provided to result in the formation of a deposit on the exteriors of the hollow fibers. The processes of this invention enable essentially the entire exterior surfaces of the hollow fibers to be coated without undue sticking of the hollow fibers or providing undesirably thick coatings on the hollow fibers in any portion of the bundle or on a portion of any of the hollow fibers.

Abstract: A supporting net is disclosed including an outer layer of first strands, said first strands being spaced apart and substantially parallel to each other; an intermediate supporting layer of second strands; and an inner layer of third strands, said third strands being spaced apart and substantially parallel to each other, said third strands being substantially parallel to said first strands and being in a spaced relationship to said first strands such that upon clamping a membrane between said supporting net and a second supporting net of the same construction the first strands of the outer layer of said second supporting net penetrate into the spaces between the third strands of the inner layer of the said supporting net so as to clamp the membrane against the intermediate supporting layers of both of the supporting nets.

Abstract: The disclosure sets forth blood processing apparatus of the general type which employs a cylindrical rotor with a semi-permeable membrane at its outer surface, rotatable within a surrounding stationary casing or housing, blood being supplied and discharged at angularly spaced loci of the casing, a secondary fluid being supplied to the interior of the rotor, effecting a cross-transfer of a component in the blood, and a secondary fluid, or a component thereof, across the membrane, sometimes referred to as a "journal machine" to distinguish such type from others which differ basically therefrom. The basic environment is like that of certain patents, identified hereinafter, and incorporates, by reference, features thereof insofar as they are applicable to the present disclosure.

Abstract: Fluoroacylation of ethyl cellulose has been found to result in good gas permeability and blood compatibility for polymeric layers made from the resulting fluorinated esters. The fluoroacylated ethyl cellulose has good hydrolytic stability at blood pH and under sterilization conditions (e.g. 100.degree. C.). For use in blood oxygenation devices, implantable biomedical devices, blood sampling of analysis or purification devices, etc., it is preferred that the fluoroacylated ethyl cellulose be substantially free of residual OH and have a fluorine content above 10% by weight (e.g. at least about 12% by weight).

Abstract: Improvements are provided in the sealing arrangment and in an inflatable shim for a membrane diffusion device which comprises a stack of membrane sections and means for defining interleaving flow paths for two different fluids, separated by the membranes.

Abstract: A membrane diffusion device, such as a membrane oxygenator, is disclosed which comprises a stack of flat membrane wall pairs and flat membrane supports in alternating, interleaving relation. The casing includes a pair of opposed sidewalls that are substantially parallel to flat sides of the stack, and a pair of substantially vertical crimps are formed on each of the sidewalls to provide external compression on the end portions of the stack.

Abstract: A method and apparatus for fluid transfer across a membrane wherein transfer fluid is passed through the interior of a wrapped, permeable, flattened, tubular membrane and fluid to be processed is passed through passageways formed between the wrappings of the tubular membrane. The exhaustion of transfer fluid begins at the completion of a process fluid pumping stroke and ends at the initiation of the pumping stroke. In a preferred embodiment the method and apparatus are utilized to oxygenate blood.

Abstract: The oxygenation and removal of carbon dioxide from blood by simultaneous mass transfer through a microporous membrane is improved by pulsing the flow of oxygenating gas over the membrane. This avoids the progressive reduction in carbon dioxide transfer rate which otherwise occurs with steady gas flow and allows such transfer rate to be maintained at an acceptable level.

Abstract: The invention concerns hollow fibre apparatus for the fractionation of fluids which comprises,a mandrel towards the ends of which two sealing elements are situated which surround the said mandrel and by which the hollow fibres are held, the fibres extending from one sealing element to the other, at least one of these sealing elements being traversed by the hollow fibres so that open ends thereof are exposed at an outer side thereof and having an inner side opposite to the inner side of the other sealing element which is inclined at least in part with respect to the longitudinal axis of the mandrel, a casing which is arranged at least around the hollow fibres and the sealing elements and which defines, between its inner wall, the inner sides of the sealing elements and the mandrel, a chamber in which the hollow fibres are arranged,first inlet and/or outlet means for introducing and/or withdrawing fluid which is circulated inside the hollow fibres, and second inlet and outlet means for introducing and withdrawi

Abstract: In a convoluted-membrane type diffusion device for blood, such as a blood oxygenator, in which the membrane is supported by a stiff, folded, integral backing having port means for fluid flow therethrough. The backing is provided with laterally positioned tabs on each edge thereof, the tabs being folded inwardly against inner portions of the backing and sealed thereto. This provides double thickness edge portions of the backing to provide spacing and a gasket seal at opposed edges of the stack of convoluted membrane layers. The backing may be coated with thermoplastic material, which may be used as an adhesive to hold the tabs in folded double thickness relation with the rest of the backing.

Abstract: Semi-permeable membranes of regenerated cellulose are subjected to wet-heat sterilization at a temperature of 105.degree. to 140.degree. C. During the treatment, the membranes are maintained in contact with an aqueous medium such as water or physiological saline. For the dialysis of body fluids, hollow fiber, semi-permeable membranes so sterilized exhibit a sonic modulus of at least 6.5.times.10.sup.10 dynes/cm.sup.2. Hollow fibers made of cuprammonium regenerated cellulose are particularly preferred for the above purpose.

Abstract: A device for exchanging substances, in particular, an oxygenator or dialyzer, comprises a stack of semipermeable membranes each having a plurality of longitudinally oriented capillaries embedded therein which open at each end. A porous tissue mass is disposed between adjacent membranes and define transverse gas flow paths therethrough from one side of said stack to the opposite side. A non-porous member closes off the top and the bottom of the stack and each longitudinal end of the tissue mass between adjacent membranes. A connecting piece is arranged at each end of the stack to provide for a flow path, for example, for blood, into the capillaries of each membrane and a similar connecting piece is arranged at the opposite end for the off-flow of the blood. Connecting pieces are arranged at each side for the inflow of a gas, for example, oxygen, into the tissues and for the outflow of the gas on the opposite side of the stack.

Abstract: A hollow fiber separatory device is provided wherein a polyurethane prepolymer is cross-linked or cured with an ester of a polyhydric alcohol which contains two or three hydroxyl groups, e.g., propylene glycol monoricinoleate, and an aliphatic acid of at least 12 carbon atoms and one or more epoxy and/or hydroxy groups per molecule.

Abstract: Blood oxygenator of the membrane type in which a semi-permeable membrane (by which is meant a membrane that is permeable to gas but not to aqueous liquid) separates the blood from the oxygen but allows diffusion of oxygen into the blood and of carbon dioxide from the blood into the stream of gas; such blood oxygenator being characterized by a plurality of oxygen, water and blood units, each blood unit having a frame which together with semi-permeable membranes forms a blood cavity, the blood entering each such unit from one side, crossing the blood cavity and exiting on the other side, such blood units being isolated from the water units such that leakage of water into the blood units is precluded. Also applicable to oxygenators in which membranes of blood units are permeable to water and small molecules but not to large molecules or particles of the blood.

Abstract: A stacked membrane apparatus for dialyzing or oxygenating blood, in which the blood compartment is isolated from the fluid (e.g., dialysate or oxygen) compartment without compressive forces being imposed by the casing to the blood manifold regions of the unit. Spaced means are provided for closing membranes about membrane support plates in such a fashion as to provide blood flow paths in the space between the closing means.

Abstract: A diffusion system for blood including a membrane diffusion device comprising a plurality of blood flow paths positioned in interleaving diffusion exchange relation, with second fluid flow paths positioned on opposite sides of semi-permeable membrane means. The first and second flow paths each communicate with an inlet and an outlet. Heat exchange means having an inlet and an outlet is connected at the inlet thereof to the outlet of the first flow paths. A rigid reservoir, also having an inlet and an outlet is connected at its inlet to the outlet of the heat exchange means. A blood flow circuit is defined through the membrane diffusion device, heat exchange means, and reservoir. The flow circuit defines an essentially constant width, perpendicular to the directions of blood flow, from its beginning to end, to provide a system having good flow distribution in combination with a low pressure drop.

Abstract: Sterilization of a dialyzer, using a saturated and wet semipermeable membrane and irradiating said dialyzer in the presence of an antibacterial agent. The method is especially effective and safe, affords elimination of labor for preparation for dialysis, and has special utility when the dialyzer is an artificial kidney containing a multiplicity of hollow filament semipermeable membranes.

Abstract: It has been found that the shelf life of stored whole blood may be doubled by adding a buffer which maintains a desired pH level. However, this buffer causes the generation of CO.sub.2 which, if not removed at a controlled rate, causes the pH value of the blood to decrease, which shortens the useful life of the blood. This invention provides a blood storage bag which permits the CO.sub.2 to be diffused out at a controlled rate into the atmosphere, thereby maintaining the desired pH value while providing a bag strong enough to permit handling thereof.

Abstract: A unit is presented for the transfer of a gaseous component in one stream to or from a liquid component in another stream, in which a membrane assembly is wound spirally around a central rigid cylindrical core. The membrane assembly comprises a continuous length of flattened tubular membrane with a gas net passing through the intermediate portion of the membrane from end to end thereof and substantially the width of the interior of the tubular membrane. In forming the coil, a net separator is wound between the membrane layers of the coil. An inlet tube for one of the components communicates with one end of the membrane and an outlet tube for the same component communicates with the other end of the membrane. Means is provided for passing another of the components longitudinally of the coil between the membrane layers from one end of the coil to the other end. The specific embodiment of a blood oxygenator is described.

Abstract: Device suitable for use in heat and mass transfer applications comprising a manifold structure having outwardly extending protrusions from the surface thereof and which is spirally wound into a plurality of convolutions and is surrounded by a shell having a cylindrical body member and conical ends. The protrusions are interconnected with one another so that flow progresses from one to another. The device can be used for heat transfer and for mass transfer between various fluid streams, in particular, venous blood and a stream of oxygen. The manifold structure being spirally wound provides a manifold for oxygen flow in an axial, as well as circumferential, direction. Blood flows axially through the mass transfer device in a plurality of essentially concentric streams. When two manifold structures are provided in tandem in a body member, both heat and mass transfer can be provided with a stream of blood.