×

Non-invasive blood pressure measurement system

  • US 9,408,542 B1
  • Filed: 07/22/2011
  • Issued: 08/09/2016
  • Est. Priority Date: 07/22/2010
  • Status: Active Grant
First Claim
Patent Images

1. A method of monitoring blood pressure of a patient, the method comprising:

  • receiving a physiological electrical signal from an electrical sensor coupled with a patient, the physiological electrical signal configured to reflect electrical activity of the patient'"'"'s heart;

    receiving a plethysmograph signal from an optical sensor coupled with a patient;

    receiving a cardiac ejection signal from a first piezoelectric acoustic sensor coupled proximate the patient'"'"'s heart, the cardiac ejection signal reflecting a cardiac ejection event associated with ejection of blood from the patient'"'"'s heart;

    calculating a centroid of a first feature in the cardiac ejection signal, the centroid corresponding to a first heart sound (S1) from the patient'"'"'s heart;

    receiving an arterial pulse signal from a second piezoelectric acoustic sensor coupled with a limb of the patient, said second piezoelectric acoustic sensor at a first distance away from the heart of the patient;

    receiving a carotid pulse signal from a third piezoelectric acoustic sensor coupled near a carotid artery of the patient, said third piezoelectric acoustic sensor at a second distance away from the heart of the patient;

    estimating, using one or more hardware processors, a pre-ejection period based on the physiological electrical signal and the cardiac ejection signal from the first piezoelectric acoustic sensor;

    estimating uncompensated pulse wave transit time (PWTT) from the plethysmograph signal and the physiological electrical signal;

    determining a first arterial PWTT that compensates for the estimated pre-ejection period of a cardiac cycle associated with the patient'"'"'s heart from the uncompensated PWTT; and

    determining a second arterial PWTT based at least partly on the cardiac ejection signal from the centroid of the first feature in the first acoustic sensor and the arterial pulse signal from the second piezoelectric acoustic sensor;

    determining a third arterial PWTT based at least partly on the cardiac ejection signal from the centroid of the first feature in the first piezoelectric acoustic sensor and the carotid pulse signal from the third piezoelectric acoustic sensor;

    comparing the first arterial PWTT, the second arterial PWTT, and the third arterial PWTT;

    determining a final arterial PWTT based on said comparison; and

    triggering an occlusive blood pressure cuff to obtain a blood pressure measurement from the patient responsive to a change in the final arterial PWTT thereby reducing instances of triggering of said occlusive blood pressure cuff for blood pressure measurement.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×