Minnesota Mining and Manufacturing Company

Thomas P Maxwell

Thomas G Hacker

Masao Yafuso

William W Miller

Mark Z Holody

John L Gehrich

Ted H Gourley

Henry K Hui

Charles M Kienholz

Cheng F Yan

John W Moers

Roxanne E Wall

A sensor cassette for use in measuring a compositional parameter of blood comprising a housing having a wall defining a passage which is adapted to receive blood. The wall is at least somewhat permeable to the compositional parameter. A support element, which is less permeable to the compositional parameter of blood than the housing, is carried by a region of the wall. A sensor is carried by the support element and provides a signal in response to the compositional parameter. The support element separates the sensor from at least a portion of such region of the wall so that the affect of the permeability of the housing to the compositional parameter on the signal from the sensor is reduced.

Apparatus and method for use in measuring a compositional parameter of

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.

Gas sensing element and method for making same

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.

Calibration system and housing

A method for making a sensing element, and an assembled sensing element, useful in sensing the concentration of a gas, e.g., carbon dioxide, in a medium, e. g. blood, are disclosed. In one embodiment, the method comprises placing a quantity of a sensing composition precursor between and in contact with a transparent, gas impermeable solid disc and an opaque, gas permeable film, the sensing composition precursor comprises a sensing component, a polymer precursor and a cross-linking agent; and forming a gas sensing composition from this quantity of sensing composition precursor.

Method for making gas sensing element

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.

Seal construction for pump apparatus

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.

One-time use disposable bottle valve

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.

Sensor and method for sensing the concentration of a component in a

Blood sensor cassette

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.

Pump and calibration system

Sterile loop calibration system

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.

Blood parameter measurement system with compliant element

An assembly useful in conjunction with a signal transmission means for the measurement of a compositional parameter of the blood of a patient is disclosed. This assembly comprises a housing adapted and sized to be located outside the body of a patient and having a fluid flow passage therethrough into which blood from the patient is passed from a hollow tube, the fluid flow passage being defined by a wall which is substantially impermeable to blood, the housing being adapted to be removeably secured to a signal transmission system such that the housing is capable of being removed from the signal transmission system without disrupting the fluid flow passage; and a sensing element located in the housing in or near the fluid flow passage for providing a signal directly to the signal transmission system in response to a compositional parameter of blood located in the fluid flow passage.

Intravascular blood gas sensing system

An apparatus for measuring the concentration of a component in a medium comprising: an optical sensor including at least one optical indicator for providing an optical signal which varies in response to the presence of a component in a medium; an optical signal fiber capable of transmitting the optical signal from the optical sensor; and a supply reservoir associated with the optical sensor and acting to provide additional optical indicator to the optical sensor.

Optical sensor

A parameter of blood is sensed with a system which includes a catheter and a sensor and a volume oscillator element. The catheter has a lumen extending therethrough, a proximal end, a distal end and an opening, adapted to be placed in the blood vessel of a patient. The sensor senses a blood parameter and is adapted to be located outside the patient's body in fluid communication with the lumen. The volume oscillator element is in fluid communication with the lumen and is capable of acting to periodically cause blood to enter and exit the lumen. The system is structured so that a flush or anti-clotting solution flows into the patient when the volume oscillator element is inactive. With the volume oscillator activated, blood is moved back and forth in the lumen to expose the sensors to blood so that the blood parameter of interest can be sensed.

Growing community of inventors

Santa Ana, CA, United States of America

Thomas P Maxwell