The present invention relates to a method and to an apparatus for continuously monitoring the membrane coupling in a pressure measurement system in a extracorporeal circuit of a blood treatment machine. The invention enables the continuous monitoring of the functionality of the pressure measurement system without an interruption of any blood treatment being necessary.

A pressure transducer comprising a flexible member made of amorphous quartz and a crystalline quartz sensor are coupled together without an adhesive material. Instead, the amorphous quartz and the crystalline quartz sensor are coupled together at the molecular level. In some embodiments, the crystalline quartz sensor remains in compression or tension during the entire operating range of the pressure transducer. In one embodiment, the crystalline quartz sensor is pre-stressed in either compression or tension when the pressure transducer is exposed to atmospheric pressure. In one embodiment, pressure transducer is located in pressure stabilizing system.

The present disclosure is directed to a catheter comprising a bendable catheter wall defining a substantially central interior lumen of the catheter, the catheter wall including a sealed chamber accommodating a fluid, the chamber substantially neighbouring the interior lumen and structured to be responsive to kinking of the catheter wall, the catheter further comprising a pressure sensor in fluid communication with the fluid, the pressure sensor configured to measure a pressure of the fluid, the pressure sensor further comprising an interface for communicating the measured pressure to a control unit, the catheter configured to allow for measurement of a change of the pressure in the fluid in response to kinking of the catheter.

A pressure sensor includes a housing that includes an interior surface and an axially symmetric liner disposed along the interior surface of the housing, where the liner includes an interior surface and an exterior surface. The pressure sensor further includes a sensing member that includes an interior surface and an exterior surface, where the interior surface of the sensing member is adjacent to the exterior surface of the liner, and the sensing member is configured to expand with the liner. The pressure sensor further includes a strain gauge affixed to the exterior surface of the sensing member.

A fluid monitoring assembly includes a segment of tubing having a wall defining a lumen through which the fluid passes and a sensor at least partially embedded within a wall of the tubing. The assembly includes a housing having first and second portions connected to one another at a hinge, the housing defining an interior portion configured to hold the segment of tubing and the sensor. The housing may be opened and closed as needed using a fastener.

A pressure testing device for calculating a pressure in a flexible line comprises a housing unit, a force sensor mounted on the housing unit and a clamp assembly having a clamp mounted on the housing unit. The clamp is operable to compress the flexible line against the force sensor by a predetermined degree of deformation of the flexible line. The device includes a displacement sensor adapted to measure a displacement of the clamp. The device also includes a controller having a processor in communication with the force sensor and the displacement sensor, and a memory unit containing stored data. At the predetermined degree of deformation of the flexible line, the processor compares a first signal from the force sensor and a second signal from the displacement senor with the stored data to estimate the pressure within the flexible line.

A subdural sensor includes: a substrate formed of a flexible material; and at least one type of sensor part mounted on the substrate. The substrate has an elongated shape, and includes: a sensor area in which the sensor part is mounted and a wiring pattern connected to the sensor part is formed; a wiring area contiguous with the sensor area, the wiring pattern extending in the wiring area; and a connector area contiguous with the wiring area, the connector area being an area on which a connector to be connected to the wiring pattern extending from the wiring area is mounted. A tip part of the sensor area has a planar shape that curves convexly toward an outer periphery, and a side shape that curves toward a first surface, the first surface being on the side of a dura mater when the subdural sensor is inserted into the subdural space.

A partially fluid-fillable circuit assembly is disclosed herein. The partially fluid-fillable circuit can include a layup composed of a substrate layer; a deformable conductor; and an encapsulation layer covering the deformable conductor. A first portion of the layup can include a sealed perimeter that, along with at least one surface defined by the layup, can define a first fluid-fillable cavity. A second portion of the layup can be unitized and structurally distinguished from the cavity defined by the first portion of the layup.