Abstract: A catheter introducer defines a tubular sheath with a housing on one end thereof, with the housing enclosing a fluid-filled, elastic-walled toroidal member defining a central aperture aligned with the tubular sheath axis. The central aperture is normally closed, being retained in the closed position by an elastic sleeve carried by the toroidal member. The central aperture is penetrable by a catheter in sealing manner as the catheter is advanced through the catheter sheath introducer.

Abstract: A hemostasis valve for a catheter such as a catheter sheath introducer comprises an elastomeric partition extending across an aperture in a hub carried by a catheter. The partition defines an annular, peripheral area which is secured to the hub. The partition further defines a second area positioned radially inwardly from the peripheral area. The second area is of substantially less thickness than the peripheral area. The partition further defines a central area positioned radially inwardly from the second area, the central area being of substantially greater thickness than the second area, and defining a slit therethrough to permit passage of the elongated member.

Abstract: A catheter introducer comprises a tubular sheath having an axis, and a housing carried on one end of the sheath. The housing encloses a fluid-filled chamber and carries a pair of valves aligned along the axis, the valves being at opposed ends of the fluid-filled chamber and communicating therewith. The valves serve to substantially retain the fluid within the housing, while allowing a catheter to pass through the valves and through the tubular sheath. The fluid of the chamber is preferably a gel or high viscosity liquid. The valves and fluid-filled chamber prevent the backflow of blood both in the presence and the absence of a catheter or the like extending through the valves and chamber.

Abstract: A valve comprises an elastomeric partition member having first and second opposed faces, the valve being adapted for securement in a housing. Typically, one or both of the faces define a recess of substantially rectangular cross section to reduce the central thickness of the partition member, the recesses being wider than they are deep. The elastomeric partition is typically made of an elastomer having an elongation of 900 to 1500 percent, a tensile strength of at least 11.5 megapascals, a Shore `A` durometer of preferably 45 to 70, and a tear strength of at least 150, as determined by tests described herein. Significant improvements are achieved by slit partition valves which utilize the elastomeric partition member of this invention.