Estimation of pressure at remote site by brachial oscillometric wave from analysis

Abstract

The present invention relates to a device and a method for estimating central systolic blood pressure based on oscillometric signals from brachial artery by the use of a pressure cuff.

1 . A method of estimating the central arterial blood pressure by measuring the signal of pulse oscillation of the brachium artery by cuff, which includes:
 (1) detecting the oscillometric waveform in the cuff;   (2) adjusting the oscillometric waveform by the average blood pressure and diastolic blood pressure measured by the cuff to calculate (I) systolic blood pressure of pulse volume recording, (II) last phase systolic blood pressure of pulse volume recording, (III) the value of the area below the waveform during systole and the area below the waveform during diastole dividing the area below the waveform during diastole, and (IV) the pressure of reflected wave hiding beneath the waveform of pressure; and   (3) bringing factor (I)˜(IV) to a formula, a regression formula, to measure the measured central arterial blood pressure, and serving the measured central arterial blood pressure as dependent variables; the factors (I)˜(IV) in Step (2) as independent variables, and then to solve the formula.   
     
     
         2 . The method of  claim 1 , wherein the measured central arterial blood pressure is obtained by invasive procedures. 
     
     
         3 . The method of  claim 1 , wherein the central artery is a carotid artery or ascending aorta. 
     
     
         4 . The method of  claim 1 , wherein the detection of the oscillometric waveform in the cuff of Step (1) includes the process of pressure decreasing in the cuff, the moment of the pressure in the cuff decreasing to a certain degree, and the oscillometric signal recorded during the process of the pressure re-increasing in the cuff.