Segmented estimation method

• US 6,017,314 A
• Filed: 04/13/1998
• Issued: 01/25/2000
• Est. Priority Date: 07/31/1996
• Status: Expired due to Fees

• Current Assignee: Medwave, Inc.
• Original Assignee: Medwave, Inc.
• Inventors: Poliac, Marius O.
• Primary Examiner(s): O'Connor, Cary
• Assistant Examiner(s): CARTER, RYAN CHRISTOPHER
• Application Number:
  US09/059,156
• Time in Patent Office: 652 Days
• Field of Search: 600/481, 600/485-486, 600/490-495, 600/499-503
• US Class Current: 600/485
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02116 of pulse wave amplitude A61B5/02225 takes precedence

Abstract

A method for determining blood pressure of an artery includes the steps of applying a pressure to the artery, sensing pressure data produced by the artery and deriving parameters for the sensed pressure data. The parameters are utilized for generating a first blood pressure value estimate using a first function of the parameters based upon a first range of pressure values and by generating at least one second blood pressure estimate using at least one second parameter function based upon a second blood pressure estimate using at least one second parameter function based upon a second pressure range different from the first pressure range. A blood pressure value is determined based upon the first blood pressure estimate and said at least one second blood pressure estimate.

Claims

1. A method for ascertaining a relationship between at least one factor and a corresponding physical results for use in estimating the result from at least one sensed factor value, the method comprising:

measuring a selected physical result to obtain result values;

sensing at least one factor of the physical result to produce at lease one sensed factor value;

ascertaining a first function based upon said at least one sensed factor value and the corresponding measured physical result values, wherein the first function estimates the physical result based upon sensed factor values;

segmenting possible physical result values into a plurality of subsets;

ascertaining a second function for each subset based upon sensed factor values and corresponding measured physical result values within each corresponding subset, wherein each second function estimates the physical result based on sensed factor values; and

ascertaining the relationship between said least one factor and the corresponding physical result based upon the first function and the second function.

2. The method of claim 1 including:

ascertaining a weighting function for each second function dependent upon results of the first function.

3. The method of claim 1 including:

ascertaining a weighting function for each second function.

4. The method of claim 3 including:

summing each weighting function multiplied by its corresponding second function.