Vital Insite, Inc.

Other

Palo Alto Research Associates

Precision Instrument Co.

William J Kaspari

Herman Wong

Kenneth H Mollenauer

Roger Alan Stern

Jeffrey M Moser

Kenneth C Kitlas

Joseph L Kirch

Donald Q Dong

Carl H Becker

Lawrence W Brendlen, Jr

Martin O'Sullivan

A blood pressure monitor for determining a patient's blood pressure comprises a processor attached to a first input device for receiving an initial input representing the patient's absolute blood pressure, and a noninvasive sensor attached to the patient for measuring at least one physiological function. The processor executes a procedure for evaluating the initial input and the sensed physiological function to determine the patient's blood pressure. A method for determining a patient's blood pressure comprises the steps of storing an initial input representing a patient's absolute blood pressure, noninvasively sensing at least one of the patient's physiological functions, and evaluating the initial input and the sensed input to determine the patient's blood pressure. The present invention can also be used to analyze and track other physiological variables such as vascular wall compliance, changes in the strength of ventricular contractions, changes in vascular resistance, changes in fluid volume, changes in cardiac output, myocardial contractility and other related factors.

Apparatus and method for noninvasive blood pressure measurement

A sensor that utilizes strips of piezoelectric material to noninvasively measure the surface force/displacement resulting from a blood pressure wave traveling through an artery and transmitted through the arterial wall and overlying tissue, while canceling noise artifact signals is disclosed. Piezoelectric elements create an electrical signal when pressure is applied to their surface. In the preferred embodiment, the sensor is constructed so that there are three sensing elements--a signal sensing element in the center and one noise sensing element on each side of the center element. The center element is placed over an individuals artery, e.g., the radial artery in a persons wrist. When positioned this way, the two noise sensing elements are positioned on each side of the artery. The center element generates a signal that is a function of the pressure wave in the artery, whereas this signal is highly attenuated in the noise sensing elements. However, all three elements detect the noise artifact signals in the general area of the sensor. The area of the noise elements, when combined, is equal to that of the center element. This provides an average of the noise detected by the center element. The signals from the two noise sensing elements are subtracted from the center element signal, thereby canceling the noise in the center element. Also disclosed is a unique method that allows repositioning of the sensor after it has been attached to the patient, a mechanism for maintaining the appropriate hold down pressure, a wrist stabilization device for stabilizing the wrist during monitoring of the blood pressure. The present invention also allows blood pressure calibrations to be obtained using the wrist and arm stabilizer assembly.

Arterial sensor

Apparatus is disclosed herein for non-invasively monitoring arterial waveforms, such as the waveform produced by blood flow through the brachial artery in a human subject. The invention includes a unique transducer which senses both a pressure wave proportional to blood flow in the artery and an acoustical signal proportional to the turbulence created by blood flow through a partially occluded artery. The transducer may be cuff mounted for attachment to the subject, and the cuff may be automatically inflated in accordance with the invention.

Non-invasive vascular waveform transducer and apparatus

A fully automatic, non-invasive, digitally-controlled blood pressure measuring apparatus is described with LED displays for displaying systolic and diastolic blood pressure levels, an inflatable cuff for occluding an artery, a pump for inflating the cuff, a cuff-mounted sensor for detecting Korotkoff sounds, adjustable gain-amplifying apparatus for maintaining linearity of the Korotkoff sound levels over a wide range of human individuals, circuits for automatically determining systolic and diastolic pressure levels and pressure release apparatus for preventing overinflation of the cuff.

Blood pressure measuring apparatus

A non-photographic, digital laser image recording and reading method and apparatus for recording and reading visual, two-dimensional replicas or representations of objects, pictures, illustrations, computer outputs and the like. A flat-field twin objective is employed to project the image of a laser beam focused to a diffraction limited spot on a radiation sensitive material, e.g., a heat ablatable or vaporizable recording medium to create a two-dimensional ensemble of holes in the recording medium. The recording medium comprises thin metallic films carried on flat substrates which are moving at constant speed or are immovably held while the image of the diffraction limited spot is scanned thereover by angularly deflecting the laser beam entering the twin objective. The visual laser record is an instantaneous replica of an original image or its computer processed binary equivalent.

Non-photographic, digital laser image recording

Growing community of inventors

Portola Valley, CA, United States of America

William J Kaspari