Maximum pulse wave amplitude calculating system and operation method for an electronic blood pressure measuring device

• US 5,385,149 A
• Filed: 09/23/1993
• Issued: 01/31/1995
• Est. Priority Date: 09/23/1992
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Nam, Sang B., Chang, Kyung S.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): NASSER, ROBERT L
• Application Number:
  US08/125,176
• Time in Patent Office: 495 Days
• Field of Search: 128/668, 128/672, 128/677, 128/680-683, 128/ 687
• US Class Current: 600/493
• CPC Class Codes: A61B 5/02116 of pulse wave amplitude A61B5/02225 takes precedence
• CPC Class Codes: A61B 5/022 by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers

Abstract

This invention, which comprises a cuff, an exhaust portion, a pressure sensor, an A/D converter, a microcomputer, a display, and an operation portion, initially determines the maximum pulse wave amplitude by comparing the size of each pulse wave, and it then determines the maximum pulse wave amplitude by comparing the sizes of the values obtained by totalling each pulse wave amplitude along with its preceding and subsequent pulse wave amplitudes, and it finally determines the maximum pulse wave amplitude by evaluating whether the different value between each preceding and each subsequent pulse wave amplitudes which occur after the maximum pulse wave amplitude has a negative(-) sign, thereby eliminating erroneous calculations caused by oscillation noise interference.

Claims

1. A maximum pulse wave amplitude calculating system for an electronic blood pressure measuring device comprising:

a cuff;

pressurizing means for pressurizing air within the cuff to a certain predetermined level;

exhaust means for exhausting the air from the cuff;

pressure sensor means for detecting pressures necessary for determining a patient'"'"'s blood pressure;

A/D converter means for converting analog signals detected by said pressure sensor means into digital signals;

microcomputer means for separately detecting pulse wave amplitudes and cuff pressure, and calculating a maximum and a minimum blood pressure by utilizing said detected signals;

operating means for operating an electric power supply, initiating blood pressure measurement, and setting a cuff pressure level; and

display means for displaying the calculated pressures,

wherein said microcomputer means includes arithmetic means which determines a maximum pulse wave amplitude by comparing sizes of values obtained by totalling each pulse wave amplitude with its preceding and subsequent pulse wave amplitudes, and determines whether said maximum pulse wave amplitude is an actual maximum pulse wave amplitude by evaluating, for each pulse wave amplitude which occurs after said maximum pulse wave amplitude, whether each value obtained by subtracting each subsequent pulse wave amplitude from each preceding pulse wave amplitude is a negative value.

2. A maximum pulse wave amplitude calculating system for an electronic blood pressure measuring device according to claim 1, wherein said display means displays the maximum and minimum blood pressures and a pulse number.

4. A method for determining the maximum pulse wave amplitude according to claim 2, wherein said step of determining comprises the step of determining that the maximum pulse wave amplitude not the actual pulse wave amplitude when the following relationships are true:

(P_1-1)+(P₁₊₁)<

<

(P_-1)+(P_n+1), and (P_a-1)+(P_a)+(P_a+1)<

P_n-1)+(P_n)+(P_n+1), or {(P_n-1)+(P_a)+(P_a+1)}/3<

{(P_n-1)+(P_n)+(P_n+1)}/3 wherein P_n represents the actual pulse wave amplitude and P_n is represents oscillation noise.

5. A method for determining the maximum pulse wave amplitude according to claim 4, wherein said step of further determining comprises the step of continuously performing the arithmetic calculation of . . . (P_a)-(P_a-1), (P_a+1)-(P_a), . . . (P_n)-(P_n-1), (P_n+1)-(P_n), (P_n+2)-(P_n+1) . . . , to determine whether the maximum pulse wave amplitude is the actual maximum pulse wave amplitude by evaluating signs for the difference values between each preceding and subsequent pulse wave amplitudes.

3. A method for determining a maximum pulse wave amplitude, comprising the steps of:

(a) graphing amplitudes of pulse work signals detected by a pulse wave detector over a specific time period,

(b) initially comparing the amplitude of each pulse wave signal to determine a maximum pulse wave amplitude,

(c) determining whether the maximum pulse wave amplitude is an actual maximum pulse wave amplitude by comparing sizes of values obtained by calculating a sum of current, preceding and subsequent pulse wave amplitudes for each pulse wave amplitude,

(d) further determining whether the maximum pulse wave amplitude is an actual maximum pulse wave amplitude by evaluating whether each value obtained by subtracting each current pulse wave amplitude from its preceding pulse wave amplitude which occurs subsequent to said determined maximum pulse wave amplitude is a negative value.

6. A method for determining a maximum pulse wave amplitude for determining a maximum blood pressure using an electronic blood pressure measuring device, comprising the steps of:

(a) storing amplitudes of pulse wave signals detected by a pulse wave detector over a specific time period,

(b) initially comparing the amplitude of each pulse wave signal,

(c) secondly determining a maximum pulse wave amplitude by comparing a size of the values obtained by calculating a sum of current, preceding and subsequent pulse wave amplitudes for each pulse wave amplitude,

(d) finally determining whether the maximum pulse wave amplitude is an actual maximum pulse wave amplitude by evaluating whether each value obtained by subtracting each current pulse wave amplitude from its preceding pulse wave amplitude which occurs subsequent to said determined maximum pulse wave amplitude is a negative value, and

(e) calculating said maximum and a minimum blood pressure values by using the determined actual maximum pulse wave amplitude.