Solid tissue impedance estimating method, cardiac output calculating method, pulmonary artery wedge pressure calculating method, cardiac output monitoring device, cardiac output monitoring system, pulmonary artery wedge pressure monitoring device, and pulmonary artery wedge pressure monitoring system

Abstract

A practical method for estimating cardiac output and pulmonary artery wedge pressure with good accuracy is provided. A method is provided for estimating the impedance arising from solid tissue by determining the impedance at the intersection between the line of identity and the extrapolated regression line, where the regression line is obtained by linearly regressing the maximum value to the minimum value of the impedance signal of each of multiple data sets, where each data set contains the maximum value and the minimum value of the impedance signal during one cardiac cycle, where impedance signal is obtained between a can electrode implanted in the left thoracic wall and an electrode inserted into the coronary vein, over a specific period of time following the infusion of hypertonic saline into the pulmonary circulation.