Impedance cardiography
Impedance cardiography (ICG; also called electrical impedance plethysmography, EIP, or thoracic electrical bioimpedance, TEB) is a non-invasive technology measuring total electrical conductivity of the thorax and its changes over time. ICG continuously processes a number of cardiodynamic parameters, such as stroke volume (SV), heart rate (HR), cardiac output (CO), ventricular ejection time (VET), and pre-ejection period; it then detects the impedance changes caused by a high-frequency, low magnitude current flowing through the thorax between additional two pairs of electrodes located outside of the measured segment.