Abstract: A parameter of blood is sensed in vivo with a system which includes a catheter and a probe. The catheter has a lumen extending therethrough, a proximal end, a distal end and a distal opening at the distal end. The probe includes one or more sensing elements at its distal end. In one embodiment, the sensing element or elements are located at least about 4 mm proximal of the distal opening of the lumen. A volume oscillator is provided to control the movement of blood into and out of the lumen. A flush solution is introduced into the lumen so that when the volume oscillator is inactive the sensing element or elements are exposed to pure flush solution, which preferably includes an anti-clotting component. The probe is received within the catheter and affixed thereto. The volume oscillator is activated to move blood into and out of the lumen to expose the sensing element or elements to blood so that they can sense the blood parameter or parameters of interest.

Abstract: An assembly for insertion into the cardiovascular system of a patient comprising a catheter having first and second lumens and a distal port. The first lumen opens at the distal port. A probe is received in the second lumen. The probe includes a sensor responsive to a constituent of blood for providing a signal which is related to the constituent. The catheter has a window for allowing the constituent of blood to pass from outside the catheter to the sensor while substantially preventing other constituents of blood from passing from the outside of the catheter to the sensor.

Abstract: Sensing composition precursors and sensing compositions, useful in sensing the concentration of a gas, e.g., carbon dioxide, in a medium, e.g., blood, are disclosed. In one embodiment, the sensing composition precursor comprises a dispersed aqueous liquid including a sensing component dissolved therein, a polymer precursor, and a hydrophilic dispersing agent selected from hydroxyalkyl celluloses and mixtures thereof in an amount effective to facilitate maintaining the dispersed aqueous liquid.

Abstract: A calibration system comprising a sensor cassette including at least one sensor to be calibrated and a housing having a liquid passage including a chamber. The housing is coupled to the sensor cassette to place the liquid passage in fluid communication with the sensor cassette. The housing has a gas injection passage through which a gas can be injected into the liquid passage to mix with a calibration liquid in the housing. A gas vent vents the gas from the housing. Porous media is provided in the chamber. The gas and calibration liquid pass through the porous media, and the porous media assists in rapid mixing of the gas and the calibration liquid.

Abstract: The present invention relates to novel orthopedic casting materials having superior layer to layer lamination, and methods for preparing the same. The orthopedic casting materials comprise a resin-coated scrim having a plurality of projections along at least one surface thereof. Preferably, each projection comprises a bundle of at least about 8 filaments, and the scrim has from about 75 to about 1500 projections per gram of scrim. The projections serve to mechanically interact with adjacent layers of the material, thereby significantly enhancing the lamination properties of the resultant material and resisting delamination once the material has cured.

Abstract: The present invention relates to novel water curable resins and orthopedic casting material incorporating such resins. The water curable resins contain agents which reduce foaming during cure. The agents are formed of an antifoaming composition sorbed on or encapsulated by a solid support. As the resin cures in water, the support disintegrates thereby activating the antifoaming composition. The antifoaming composition is preferably a polysiloxane.

Abstract: A method for determining the concentration of a constituent of blood employing a sensor in or near a catheter in a blood vessel for producing a signal related to the concentration of the constituent of blood is disclosed. The improvement comprises obtaining the signal while at least one of the following is present in the blood vessel: (1) an added vasodilator component and/or vasodilation promotor in an amount effective to reduce the vasoconstriction caused by the presence of the catheter in the blood vessel and (2) an added platelet/white cell inhibitor component and/or a platelet/white cell deactivation promotor in an amount effective to reduce the platelet and/or white cell activation caused by the presence of the catheter in the blood vessel.

Abstract: The present invention relates to an orthotic blank comprising an open-celled foam sheet impregnated with a water curable, isocyanate functional, polyurethane prepolymer resin. The orthotic blank can be used according to the method of this invention to prepare an orthotic pad bearing the impression of a body part to be supported and/or cushioned. The resultant orthotic pad exhibits both proper weight-bearing strength and cushioning properties for effective and comfortable use.

Abstract: An endless path calibration system comprising a sensor cassette having a flow-through passage and at least one sensor to be calibrated, a chamber coupled to the sensor cassette to define an endless path and a sterile calibration liquid in the endless path. A gas injection passage for injecting gas into the sterile calibration liquid and a gas vent leading from the endless path to the exterior of the endless path. A check valve allows gas to escape from the endless path and substantially prevents gas and liquid from entering the endless path through the gas vent.

Abstract: A system for determining the value of a compositional parameter of blood, including a sensor for producing a signal related to the value of the compositional parameter. A computer analyzes the signal and produces an output representing the value of the compositional parameter of blood. There is a delayed response in the system such that the signal has a time-varying waveform that varies from an initial value to an equilibrated value. The equilibrated value is predicted by detecting the occurrence of an inflection point and then computing an estimate of the equilibrated value based upon the assumption that the waveform varies exponentially from the inflection point to the equilibrated value.

Abstract: An apparatus for holding a fluid under pressure, including a container for containing the fluid under pressure and a valve mounted on the container. The container has a passage leading to the exterior of the container, and the valve has an actuator for moving the valve between closed and open positions. A locking device is responsive to movement of the actuator to a position in which the valve is open to lock the actuator against movement that would close the valve. Consequently, the valve is locked in the open position.

Abstract: An apparatus for sensing the concentration of a component such as oxygen in a medium such as blood. The apparatus includes an elongated signal transmitter and a sensing element at one end thereof. A substantially rigid sleeve is secured around such end to provide a pocket for the sensing element.

Abstract: An apparatus comprising a supporting structure having a surface, an optical sensor for sensing a compositional blood parameter and a deformable optical coupling element carried by the supporting structure. The optical sensor is carried by the supporting structure and is responsive to an optical input signal to provide an optical output signal related to the compositional blood parameter. The optical coupling element is in a position to receive at least one of the optical signals and the optical coupling element is transmissive to such received signal.

Abstract: An apparatus comprising a housing, a curved wall surface on the housing and a tube compressor carried by the housing. A compressible tube, which defines at least a portion of the passage, is positioned between the curved wall surface and the tube compressor. The tube compressor is mounted on the housing for free radial movement relative to the curved wall surface and for rotational movement. The tube compressor can be releasably drivingly coupled to an external rotary input so that the tube compressor can be rolled along the tube to pump fluid in the tube.

Abstract: A composition of matter useful in a sensor for sensing the concentration of an ionic component a medium is disclosed. This composition comprises a first material including a sensing component in an amount effective to provide a signal which varies as the concentration of the ionic component in the medium varies, and a first matrix material, and a second material which includes a second matrix material which is compatible with the first matrix material, and an opague agent in an amount sufficient to render the second material effectively opaque. The first material and the second material are partially intermingled. Apparatus including such composition of matter and methods for making and using such compositions of matter are also disclosed.

Abstract: A composition of matter useful in a sensor for sensing the concentration of an ionic component in a medium is disclosed. This composition comprises a first material which includes a sensing component in an amount effective to provide a signal which varies as the concentration of the ionic component in the medium varies, and a first matrix material which is permeable to the ionic component; and a second material which includes a second matrix material which is permeable to the ionic component, and an opaque agent in an amount sufficient to render the second material effectively opaque. The first material matrix and the second matrix material are covalently bonded together. Sensing apparatus including such composition of matter and methods for making and using such composition of matter are also disclosed.

Abstract: A sensor comprising a sensing element capable of sensing a component in an aqueous medium and an overcoating at least partially covering the sensing element. The overcoating comprises a water insoluble, component permeable, cross-linked cellulosic material and an effective amount of an opaque agent.

Abstract: An endless path calibration system comprising a sensor cassette having a flow-through passage and at least one sensor to be calibrated, a chamber coupled to the sensor cassette to define an endless path and a sterile calibration liquid in the endless path. A gas injection passage for injecting gas into the sterile calibration liquid and a gas vent leading from the endless path to the exterior of the endless path. A check valve allows gas to escape from the endless path and substantially prevents gas and liquid from entering the endless path through the gas vent.

Abstract: The present invention relates to colored orthipedic resins and colored orthopedic casting materials which are storage stable. In making the colored orthopedic resins and colored orthopedic casting materials, a chromophore-containing polyol is covalently bonded into a prepolymer resin.

Abstract: An assembly for the measurement of a blood parameter comprising a catheter having a lumen extending therethrough and a sensor mounted in the lumen. A conduit couples the lumen to a source of anti-clotting solution, and a compliant element is coupled to the conduit to allow the volume of the introducing system to be expanded and contracted. The compliance of the compliant element can be adjusted to thereby adjust the compliance of the assembly.