Automatic oscillometric apparatus and method for measuring blood pressure
AssigneeGE Medical Systems Information Technologies, Inc.
InventorsJohn W. Booth, Bruce A. Friedman
Life of this patent
Estimating the term…
Abstract
Blood pressure of an human being is read by a process that places a cuff around a portion of the human being's body. The cuff is inflated to a predefined pressure which occludes the flood of blood and then the cuff is deflated in a controlled manner. At a plurality of deflation pressure levels, pressure pulses that occur in the cuff are integrated to produce a plurality of integral values. A diastolic pressure of the human being is derived in response to the deflation pressure level at which occurred the integral value that is greatest in magnitude.
Claims20
A method for indirectly measuring blood pressure comprising:
- placing a cuff around a portion of a human being;
- varying pressure within the cuff to produce a plurality of cuff pressure levels;
- while at a given cuff pressure level, measuring and storing the given cuff pressure level and a plurality of pressure oscillation amplitude values to produce a pressure oscillation waveform, thereby producing a plurality of measurements;
- integrating a plurality of pressure oscillations of the pressure oscillation waveform to produce a plurality of integral values;
- and
- deriving a first estimate of diastolic pressure for the human being in response to the cuff pressure level which occurred coincident with the pressure oscillation which produced the integral value that is greatest in magnitude.
A method for indirectly measuring blood pressure comprising the steps of:
- (a) placing a cuff around a portion of a human being's body;
- (b) inflating the cuff to a predetermined pressure;
- (c) periodically measuring pressure in the cuff thereby producing an oscillation pressure waveform;
- (d) deflating the cuff by a predetermined increment of pressure, which results in a deflation pressure in the cuff;
- (e) repeating the steps (c) and (d) for a plurality of times thereby producing a plurality of oscillation pressure waveforms;
- (f) utilizing an oscillometric technique to estimate a systolic pressure and a mean arterial pressure for the human being from a plurality of oscillation amplitudes derived from the oscillation pressure waveforms;
- (g) integrating the plurality of measurements taken during each different deflation pressure to derive an integral value for each different deflation pressure;
- and
- (h) deriving a first estimate of diastolic pressure of the human being from the deflation pressure associated with the greatest integral value.
An apparatus for producing information indicative of blood pressure of an human being through indirect measurement comprising:
- an inflatable cuff;
- a pump connected to the cuff, for inflating the cuff to a pressure above systolic pressure of the human being;
- a deflating valve connected to the cuff to release fluid from within the cuff thereby varying pressure within the cuff;
- a transducer that measures pressure oscillations in the cuff caused by heartbeats of the human being;
- and
- a controller responsive to the transducer for initially energizing the pump to inflate the cuff and subsequently energizing the deflating valve incrementally to deflate the cuff at predetermined pressure increments, wherein the controller integrates the pressure oscillations occasioned by successive heartbeats to produce a plurality of integral values and identifies as a diastolic pressure, the pressure which occurs in the cuff when the pressure oscillations have an integral value of greatest magnitude.
Dependencies are inferred from the claim text.