Abstract: Medical tubing carries on at least a portion of its length a water-activated lubricating coating of a hydrophilic thermoplastic resin which is adhesively compatible with the material of the medical tubing and polyvinyl pyrrolidone having a molecular weight of at least 200,000, in the form of a dispersed separate phase in the thermoplastic resin upon hydration. The polyvinyl pyrrolidone provides long-lasting lubrication when wet.

Abstract: Disclosed is an improved process for oxidizing chromium in deposits in the cooling system of a nuclear reactor using a solution of ozone. The improvement consists of adding to the solution about 0.01 to about 0.5% of a water-soluble cerium IV compound, about 0.1 to about 0.5% of a water-soluble aromatic compound having at least one ketone group on an aromatic ring, or adding both. Also disclosed is the composition of water, ozone, the cerium IV compound and the aromatic compound. Also disclosed is a process for decontaminating the cooling system of nuclear reactors by adding a decontamination composition to the coolant, circulating the coolant between the cooling system and a cation exchange resin, removing the decontamination composition by passing it through an anion exchange resin, adjusting the temperature to 40.degree. to about 100.degree. C., adding the ozone oxidation composition, circulating the coolant through the cooling system, raising the temperature to at least about 100.degree. C.

Abstract: A method for decontaminating metal surfaces having radioactive oxide deposits thereon is disclosed which comprises preparing a decontamination solution having a pH of about 1.5 to about 4 comprising water, about 0.02 to about 0.5% of a water soluble organic acid which has an equilibrium constant in a complex with ferric ion of at least about 10.sup.9 and which is capable of producing a pH of about 2 to about 3 in water, and about 0.01 to about 0.4% of a chelate in free acid form which has an equilibrium constant in a complex with ferric ion of about 10.sup.15 to about 10.sup.19 and which is at least 0.4% soluble at 40.degree. C. in water having a pH of about 2 to about 3. An apparatus for performing the above method is disclosed.

Abstract: A silicone rubber catheter carries radiopaque stripes comprising a mixture of silicone rubber and the finely divided radiopaque material, the stripes being spaced from each other by transparent, longitudinal segments. The radiopaque stripes are preferably positioned in diametrically opposed, spaced relation to each other about the circumference of the catheter and occupy a total of 50.degree. to 270.degree. of the catheter circumference. The elongation of the catheter portion defining the stripes is preferably at least as great as the elongation of the catheter portion defining the transparent, longitudinal segments, and the tensile and tear strengths of the transparent segments are preferably higher, so that upon stretching of the catheter most of the stress can be diverted to the transparent segments of the catheter.

Abstract: A thermoplastic member such as a length of tubing for forming a catheter balloon is sealed by radiant heat to a thermoplastic shaft of a medical device such as a Foley catheter. Radiant heat is supplied as a narrow annular band by an apparatus which also automatically locates portions of the shaft at the narrow annular band. A length of shrink tubing is placed over the balloon tubing and adjoining portions of the shaft, is then preshrunk while at that location, and is further shrunk therearound and is subjected to radiant heat by the apparatus in order to seal the balloon tubing onto the shaft and complete assembly of a balloon catheter. It is especially preferred that the shrink tubing be tinted so as to enhance the seal formed beneath the shrink tubing.

Abstract: Apparatus for protecting a pressure-sensitive transducer in an extracorporeal blood system and for providing a sterile barrier while the apparatus transmits the blood pressure to the pressure-sensitive transducer. The apparatus (34) comprises a housing (40, 42) having first (40) and second (42) generally hemispherical members which symmetrically enclose a generally planar silicone membrane diaphragm (44). The membrane diaphragm (44) has a thickness that is less than 0.040 inch and a diameter that is at least twice as great as the intended total deflection distance. The membrane (44) is centered within the housing (40, 42) and greater pressure on either side of the membrane (44) will cause the membrane (44) to deflect to the other side by stretching.

Abstract: A thermoplastic composition is disclosed which consists essentially of a major portion of a first poly(ethylene-vinyl acetate) copolymer which contains from 22 to 30 percent by weight of vinyl acetate units and exhibits a melt index as defined herein of 0.5 to 10. A minor portion of a second poly(ethylene-vinyl acetate) copolymer is included which contains from 25 to 40 percent by weight of vinyl acetate units, the second copolymer exhibiting a melt index of 20 to 1000. The resulting formulation exhibits numerous good properties for use in medical devices, coupled with the capacity for radiation sterilization.

Abstract: A thermoplastic member such as a length of tubing for forming a catheter balloon is positioned on the thermoplastic shaft of a medical device. A length of shrink tubing is placed over each end of the balloon tubing and adjoins a portion of the shaft. Each length of shrink tubing may then be preshrunk to maintain its position. The shaft, balloon tubing, and shrink tubing are then inserted in an apparatus capable of supplying radiant heat in a narrow annular band. The apparatus automatically positions each portion of the shaft and balloon tubing covered by shrink tubing at a location at which it will intercept the narrow annular band of radiant heat. Radiant heat is supplied by the apparatus to cause further shrinkage of the shrink tubing and to seal the balloon tubing onto the shaft. The shrink tubing may be removed to complete the assembly of a balloon catheter. It is preferred that the shrink tubing be tinted so as to enhance the seal formed between the balloon tubing and the shaft.

Abstract: A catheter, preferably a balloon-type catheter, is disclosed in which the catheter shaft is made of a thermoplastic material and thus may be extrudable, the shaft consisting essentially of (a) from 40 to 70 percent by weight of an elastic composition which comprises: from 50 to 99.5 percent by weight of a block copolymer having thermoplastic rubber characteristics with a central, rubbery polyolefin block and terminal blocks of polystyrene, and optionally including up to about 45 percent by weight of polypropylene, plus from 0.5 to 10 percent by weight of a cross-linked organic silicone elastomer; and (b) from 30 to 60 percent by weight of a hydrophobic oil-type plasticizer to provide the desired degree of softness to said elastic composition.

Abstract: A flexible composition which is preferably radiopaque comprises a plastic material which may be mixed with from 10 to 50 percent by weight of a radiopaque filler. The plastic material comprises the product of (a) a block copolymer having thermoplastic, rubbery characteristics, having a central rubbery olefin block and terminal blocks of a polystyrene; (b) low crystallinity ethylene polymers such as poly (ethylene-vinyl acetate); and (c) a silicone gum containing a small amount of a silicon-bonded olefin group such as vinyl. Optionally, the addition of 5 to 40 percent by weight polypropylene may be included in these materials to improve their heat resistance and strength without affecting their transparency, when transparent materials are formulated.

Abstract: A balloon-type catheter is disclosed having a catheter shank made of a block copolymer having thermoplastic rubber characteristics with a central block of ethylene-butylene copolymer and terminal blocks of polystyrene. The inflatable balloon member, and preferably the distal Y-member, of the catheter are made of an elastic composition which includes the same or a similar block copolymer, in the presence of polystyrene or equivalent material as a tackifying agent, polypropylene, and an oil-type plasticizer.