Hand-held non-invasive blood pressure measurement device

• US 6,340,349 B1
• Filed: 04/22/1999
• Issued: 01/22/2002
• Est. Priority Date: 11/09/1993
• Status: Expired due to Fees

• Current Assignee: Medwave, Inc.
• Original Assignee: Medwave, Inc.
• Inventors: Thede, Roger C., Curran, Timothy G., Poliac, Marius O., Archibald, G. Kent, Danielson, Orland H.
• Primary Examiner(s): Gilbert, Samuel G.
• Application Number:
  US09/296,994
• Time in Patent Office: 1,006 Days
• Field of Search: 600/490-499, 600/485
• US Class Current: 600/494
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 5/02116 of pulse wave amplitude A61B5/02225 takes precedence
• CPC Class Codes: A61B 5/02233 Occluders specially adapted therefor tourniquets A61B17/132
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure

Abstract

A hand-held non-invasive blood pressure measurement device allows a varying pressure to be applied to an artery while pressure waveforms are sensed to produce pressure waveform data. Waveform parameters are derived from the sensed pressure waveform data. Blood pressure is then determined using the derived parameters. The user is guided or prompted to apply the varying pressure through audible and visual feedback.

Claims

1. A non-invasive blood pressure measurement device comprising:

a housing shaped to be gripped by a user to apply force toward the artery;

a transducer having a sensing surface;

a flexible diaphragm for being positioned over the underlying artery wherein the flexible diaphragm is mounted on a sensor assembly which is connected to the housing to pivot about at a position proximate the flexible diaphragm;

interface means between the flexible diaphragm and the sensing surface of the transducer for transmitting pressure from the diaphragm to the transducer;

signal producing means connected to the transducer for producing output signals corresponding to the sensed pressure data; and

processing means for receiving the output signals from the signal producing means, for deriving a plurality of parameters using sensed pressure and for determining a blood pressure value using the derived parameters.

2. A non-invasive blood pressure measurement device comprising:

a housing shaped to be gripped by a user to apply force toward the artery;

means for sensing pressure from the artery over time while the pressure is applied to the artery to generate pressure data, the means for sensing including;

a transducer having a sensing surface;

a flexible diaphragm for being positioned over the underlying artery wherein the flexible diaphragm is mounted on a sensor interface assembly which is pivotally attached to the housing with a pivot point located proximate the flexible diaphragm;

interface means between the flexible diaphragm and the sensing surface of the transducer for transmitting pressure pulses from the diaphragm to the transducer; and

means for deriving a pressure value based upon a waveform analysis of the pressure data.

3. A method for determining blood pressure of an artery, the method comprising:

positioning a sensor having a constant volume fluid filled sensing chamber with a flexible diaphragm over the artery;

manually applying force to the sensor, which is pivotable about a pivot point proximate the flexible diaphragm, to press the sensor towards the artery;

sensing pressure data produced by the artery by sensing pressure within the constant volume fluid filled chamber to generate pressure waveform data;

deriving parameters from the pressure data; and

determining a blood pressure value based upon the parameters.

4. A non-invasive blood pressure measurement device comprising:

a sensor having a constant volume fluid filled sensing chamber with a flexible diaphragm configured for being positioned over an underlying artery;

force applying means for applying a force to the sensor to press the sensor, which is pivotable about a pivot point located proximate the flexible diaphragm, against the underlying artery;

sensing means for sensing pressure within the constant volume fluid filled sensing chamber representing pressure data produced by the underlying artery;

signal producing means connected to the sensing means for producing output signals corresponding to sensed pressure within the constant volume fluid filled sensing chamber; and

processing means for determining a blood pressure value based upon the output signals.

5. A non-invasive blood pressure measurement device comprising:

a sensor having a constant volume fluid filled sensing chamber with a diaphragm configured for being positioned over an underlying artery;

means, pivotally connected to the sensor to pivot about a pivot point proximate the diaphragm, for applying force to the sensor to press the sensor against the underlying artery;

a transducer for sensing pressure within the constant volume fluid filled sensing chamber; and

means for deriving a blood pressure value based upon a waveform analysis of the sensed pressure.

6. A device for sensing blood pressure within an underlying artery of a patient, the device comprising:

a fluid filled sensing chamber having a diaphragm;

a transducer fluidly coupled to the fluidly filled sensing chamber, wherein the transducer senses fluid pressure within the chamber;

a flexible body conformable wall proximate the sensing chamber and isolated from the sensing chamber for applying force to the artery while preventing pressure in a direction generally parallel to the artery from being applied to the sensing chamber; and

a housing, connected to the wall so that the wall and the chamber are pivotable about a pivot point proximate the diaphragm, for applying force to apply pressure to the artery.

7. A device for sensing blood pressure pulses within an underlying artery surrounded by tissue as the underlying artery is compressed, the sensor comprising:

a transducer;

a flexible diaphragm for placement above the underlying artery;

a fluid coupling medium between the transducer and the flexible diaphragm, wherein the fluid coupling medium transmits blood pressure pulse signals from the underlying artery to the transducer;

a flexible, variable height, body conforming sidewall isolated from the fluid coupling medium and positioned for engaging tissue proximate to the underlying artery; and

means, pivotally connected to the sidewall so that the sidewall and the flexible diaphragm are pivotable about a pivot point adjacent the flexible diaphragm, for manually applying pressure to the artery.

8. A device for external measurements of blood pressure in an underlying artery surrounded by tissue of a patient, the system comprising wherein the sensing means includes:

a transducer having a sensing surface;

a flexible diaphragm for being positioned over the underlying artery; and

an interface between the flexible diaphragm and the sensing surface of the transducer through which pressure pulses are transmitted from the diaphragm to the transducer;

means for applying a variable pressure to the sensing means through a pivoted connection having a pivot point located proximate the flexible diaphragm; and

means for calculating blood pressure based upon a pressure at maximum energy transfer and shape of the sensed pressure pulses within the underlying artery.