Thoracic Impedance

Thoracic Impedance is a measure of the electrical activity in the chest that varies with changes in body size and composition, fluid volume, ventilation status, and heart characteristics such as cardiac output and stroke volume. Our goal was to measure respiration rate. During inspiration, there is an increase in the gas volume of the chest in relation to the fluid volume; this increase causes conductivity to decrease. The length of the conductance paths also increases because of expansion.”

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