Stephen J Martin

US Patent:

6290650, Sep 18, 2001

Filed:

May 28, 1999

Appl. No.:

9/321907

Inventors:

Robert D. Butterfield - Poway CA
Kenneth J. Pytel - San Diego CA
Charles R. Holdaway - San Diego CA
Stephen A. Martin - Carlsbad CA

Assignee:

Alaris Medical Systems, Inc. - San Diego CA

International Classification:

A61B 502

US Classification:

600485

Abstract:

A system for noninvasively continuously monitoring arterial blood pressure includes a tissue stress sensor that has a continuous diaphragm for sensing stress within tissue adjacent a preselected artery caused by arterial pulsations within that artery. The stress sensitive diaphragm is coupled with electromechanical means for producing electrical signals that represent the stress within the tissue that is communicated to the sensor. These signals are then processed electronically in order to yield an output that is indicative of the arterial blood pressure of the preselected artery. The disclosed system includes methods of operation for determining blood pressure while maintaining a preselected artery in an optimum applanation state and an off-optimum applanation state.

US Patent:

56178670, Apr 8, 1997

Filed:

Nov 23, 1994

Appl. No.:

8/344252

Inventors:

Robert D. Butterfield - Poway CA
Charles R. Holdaway - San Diego CA
Stephen A. Martin - San Diego CA
Stanley J. Boyer - Carlsbad CA

Assignee:

IVAC Medical Systems, Inc. - San Diego CA

International Classification:

A61B 500

US Classification:

128672

Abstract:

A device for mounting a tonometry sensor upon a patient's wrist includes a base portion that is specifically adapted to generally conform to the patient's wrist while providing a stable placement of the tonometry sensor relative to a preselected artery. A sensor housing is movably mounted upon the base portion and configured such that the mounting device has an essentially equal thickness at each end of the device. A strap member is provided for releasably securing the mounting device to a patient's wrist. The mounting device facilitates more accurate, non-invasive blood pressure measurement by providing a stable placement of the tonometry sensor relative to the tissue overlying a preselected artery at a measurement location and, further, limits undesirable movement by the patient to thereby reduce undesirable error in the blood pressure measurement.

US Patent:

55633471, Oct 8, 1996

Filed:

Sep 12, 1994

Appl. No.:

8/305465

Inventors:

Stephen A. Martin - Carlsbad CA
Robert D. Butterfield - Poway CA
Charles E. Clemens - Encinitas CA

International Classification:

G01L 700

US Classification:

73756

Abstract:

A pumping segment for incorporation into a fluid delivery system, the segment having a dome-shaped pressure vessel with an optimal shape for interfacing with a pressure sensing element, and which is capable of uniformly distributing pressure across its interfacing structure and being optimally pre-loaded against the pressure sensing element. The pumping segment including a lateral restraint to inhibit rupture of the unloaded pressure vessel when experiencing high internal pressures.

US Patent:

52614123, Nov 16, 1993

Filed:

Nov 20, 1992

Appl. No.:

7/980931

Inventors:

Robert D. Butterfield - Poway CA
Stephen A. Martin - Carlsbad CA

Assignee:

IVAC Corporation - San Diego CA

International Classification:

A61B 502

US Classification:

128672

Abstract:

A method, for use in a non-invasive blood pressure monitoring system, of operating a tissue stress sensor at an off-optimum arterial applanation state. The system uses a stress sensor including a stress sensitive element for detecting stress of tissue overlying an artery of interest. The tissue stress sensor is placed in communication with tissue overlying the artery of interest and at least one electrical signal is obtained therefrom representing stress data across the length of the stress sensitive element. The data represents stress datum communicated to preselected portions of the stress sensitive element. From the stress datum, various techniques are used to determine the optimum applanation state and the actual applanation state. A waveform scaling factor function is created which compensates for the errors associated with operating the tissue stress sensor at an off-optimum applanation state. Thus, the disclosed method provides the benefits associated with operating a tissue stress sensor at an off-optimum state without sacrificing measurement accuracy.

US Patent:

52841502, Feb 8, 1994

Filed:

Oct 16, 1992

Appl. No.:

7/962364

Inventors:

Robert D. Butterfield - Poway CA
Kenneth J. Pytel - San Diego CA
Charles R. Holdaway - San Diego CA
Stephen A. Martin - Carlsbad CA

Assignee:

IVAC Corporation - San Diego CA

International Classification:

A61B 5021

US Classification:

128672

Abstract:

A tissue contact stress sensing system incorporates a semiconductor assembly and a continuous diaphragm to noninvasively determine the intra-arterial blood pressure of a patient. The system comprises a continuous diaphragm placed against a patient's tissue which covers an underlying artery. The semiconductor assembly is placed in close proximity to and spaced apart from the diaphragm for directly irradiating the diaphragm with electromagnetic radiation and receiving a portion of the electromagnetic radiation which is reflected from the continuous diaphragm. The disclosed system also utilizes a technique for minimizing the system errors associated with temperature drift and aging of the sensor.

US Patent:

52634841, Nov 23, 1993

Filed:

Feb 13, 1992

Appl. No.:

7/835634

Inventors:

Stephen A. Martin - Carlsbad CA
Robert D. Butterfield - Poway CA

Assignee:

IVAC Corporation - San Diego CA

International Classification:

A61B 502

US Classification:

128672

Abstract:

A method, for use in a non-invasive blood pressure monitoring system, of determining which portion of a stress sensitive element of a tissue stress sensor is best located for detecting the stress of tissue overlying an artery of interest. The tissue stress sensor is placed in communication with tissue overlying the artery of interest and a plurality of electrical signals are obtained therefrom representing stress data across the length of the stress sensitive element. Each electrical signal represents stress datum communicated to a predetermined portion of the stress sensitive element. From the stress datum, a centroid of energy is computed and the centroid of energy is used to determine which portion of the stress sensitive element is best located for determining the blood pressure within the artery of interest. A second method is disclosed which uses the centroid of a tissue foundation flexibility function to determine the best location along the stress sensitive element for determining blood pressure.

US Patent:

52730468, Dec 28, 1993

Filed:

Apr 15, 1992

Appl. No.:

7/869553

Inventors:

Robert D. Butterfield - Poway CA
Stephen A. Martin - Carlsbad CA

Assignee:

IVAC Corporation - San Diego CA

International Classification:

A61B 502

US Classification:

128672

Abstract:

A method, for use in a non-invasive blood pressure monitoring system, of determining optimum artery applanation. The system uses a stress sensor including a stress sensitive element for detecting stress of tissue overlying an artery of interest. The tissue stress sensor is placed in communication with tissue overlying the artery of interest and at least one electrical signal is obtained therefrom representing stress data across the length of the stress sensitive element. The data represents stress datum communicated to a preselected portion of the stress sensitive element. From the stress datum, various algorithms are used, singly or in combination, to provide the best measure of optimum applanation state. Intra-arterial blood pressure is then calculated using datum collected at the optimum applanation state. In addition, to the optimum applanation methods, a method is disclosed for determining which portion of the stress sensitive element is best suited for estimating intra-arterial blood pressure.

US Patent:

51580918, Oct 27, 1992

Filed:

Nov 30, 1990

Appl. No.:

7/621165

Inventors:

Robert D. Butterfield - Poway CA
Kenneth J. Pytel - San Diego CA
Charles R. Holdaway - San Diego CA
Stephen A. Martin - Carlsbad CA

Assignee:

IVAC Corporation - San Diego CA

International Classification:

A61B 5021

US Classification:

128672

Abstract:

A tissue contact stress sensing system incorporates a semiconductor assembly and a continuous diaphragm to noninvasively determine the intra-arterial blood pressure of a patient. The system comprises a continuous diaphragm placed against a patient's tissue which covers an underlying artery. The semiconductor assembly is placed in close proximity to and spaced apart from the diaphragm for directly irradiating the diaphragm with electromagnetic radiation and receiving a portion of the electromagnetic radiation which is reflected from the continuous diaphragm. The disclosed system also utilizes a technique for minimizing the system errors associated with temperature drift and aging of the sensor.