Pressure measurement device

• US 7,347,822 B2
• Filed: 12/14/2005
• Issued: 03/25/2008
• Est. Priority Date: 10/14/1997
• Status: Expired due to Fees

• Current Assignee: Data Sciences U K Limited (International Business Machines Corporation)
• Original Assignee: Transoma Medical, Inc.
• Inventors: Brockway, Brian P., Mills, Perry Alton, Moench, Mel Murray
• Primary Examiner(s): Nasser; Robert L.
• Application Number:
  US11/304,452
• Publication Number:
  US 20060094966A1
• Time in Patent Office: 832 Days
• Field of Search: None
• US Class Current: 600/486
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61M 2025/0003 having an additional lumen transmitting fluid pressure to the outside for measurement

Abstract

A device measures pressures in animals and humans and includes a pressure transmission catheter (PTC) filled with a pressure transmitting medium and implantable in an area in having a physiological pressure. A transducer communicates with the pressure transmitting medium to provide a pressure signal representing variations in the physiologic pressure on electrical wires. A connecting catheter carries the electrical wires to signal processing and telemetry circuitry, which transmits a telemetry signal representing the pressure signal to a receiver external to the animal or human. A housing holds the signal processing and telemetry circuitry, but the transducer is remote from the housing. The device is particularly useful in measuring venous pressure, pulmonary pressure, bladder pressure, or intracranial pressure without significant head pressure artifact and with a sufficient dynamic response. One embodiment of the PTC includes a multi-durometer stem.

Claims

1. An apparatus for measuring physiological pressure comprising:

a pressure transmission catheter having a lumen filled with a pressure transmitting medium and implantable in an area having a physiological pressure;

a transducer in communication with the pressure transmitting medium and coupled to an electrical wire for providing a signal representing variations in the physiologic pressure on the electrical wire;

a connecting catheter carrying the electrical wire to a location remote from the transducer;

the pressure transmitting catheter comprising an inner layer defining the lumen and an outer layer disposed about the inner layer, wherein;

the inner layer comprises a first material, and

the outer layer comprises a second material that is softer than the first material, wherein the pressure transmission catheter has a length short enough to avoid significant head pressure artifact and provide sufficient dynamic response.

2. An apparatus for measuring physiological pressure comprising:

a pressure transmission catheter having a lumen filled with a pressure transmitting medium and implantable in an area having a physiological pressure;

a transducer in communication with the pressure transmitting medium and coupled to an electrical wire for providing a signal representing variations in the physiologic pressure on the electrical wire;

a connecting catheter carrying the electrical wire to a location remote from the transducer;

the pressure transmitting catheter comprising an inner layer defining the lumen and an outer layer disposed about the inner layer, wherein;

the inner layer comprises a first material, and

the outer layer comprises a second material that is softer than the first material, wherein the pressure transmitting medium comprises a slidable plug and a low-viscosity liquid.

3. An apparatus for measuring physiological pressure comprising:

a pressure transmission catheter having a lumen filled entirely with a pressure transmitting gel and implantable in an area having a physiological pressure; and

a transducer in communication with the pressure transmitting gel and coupled to an electrical wire to provide a signal on the electrical wire which represents variations in the physiologic pressure;

the pressure transmitting catheter compromising an inner layer defining the lumen and an outer layer disposed about the inner layer, wherein;

the inner layer comprises a first material having a first hardness,

the outer layer comprises a second material having a second hardness, and the first hardness is greater than the second hardness, wherein the electrical wire is carried within a connecting catheter carrying the electrical wire to a location remote from the transducer wherein the pressure transmission catheter has a length short enough to avoid significant head pressure artifact and provide sufficient dynamic response.

4. An apparatus for measuring physiological pressure comprising:

a pressure transmission catheter having a lumen filled entirely with a pressure transmitting gel and implantable in an area having a physiological pressure; and

a transducer in communication with the pressure transmitting gel and coupled to an electrical wire to provide a signal on the electrical wire which represents variations in the physiologic pressure;

the pressure transmitting catheter compromising an inner layer defining the lumen and an outer layer disposed about the inner layer, wherein;

the inner layer comprises a first material having a first hardness,

the outer layer comprises a second material having a second hardness, and the first hardness is greater than the second hardness, wherein the electrical wire is carried within a connecting catheter carrying the electrical wire to a location remote from the transducer wherein the pressure transmission catheter has a length in the range from approximately two millimeters to approximately four centimeters.