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Figure 5.3 Electrodes and arrangement for the measurement of the electrical impedance in SV estima-
tion: (Left) Kubicek bioimpedance (Kubicek et al., 1966), (Middle) Sramek bioimpedance (Sramek, 1986),
(Right) IRB (Tishchenko, 1973).
where P is the patient’s weight, P IDEAL (H) is the “ideal weight,” defined for women
and men, which is function of the patient’s height, H. Equations (5.6) and (5.7) yield

V EPT dZ tðÞ
ΔV SV 52 min T E : ð5:8Þ
Z tACycle dt
which is the SV evaluated in the Kubicek bioimpedance technology.
TEB is used for cardiac investigation and diagnosis in a clinical environment
(Bernstein, 2010; Sathyaprabha et al., 2008) to continuously monitor the aortic
blood flow (Funk et al., 2009; Truijen et al., 2012). TEBdynamicsisrelated to,
and might be synchronized and related with the respiratory and ECG vital signs,
which offer consistent data for the evaluation of SV, CO, as well as the peak aortic
acceleration of blood (PAA), systemic vascular resistance (SVR), velocity of the
blood flow (VBF), and flow time (FT) (Osypka, 2009; Stevanovi´ c et al., 2008;
Ipate et al., 2012).
NASA developed TEB, and introduced the ICG in 1967. In the 1980s, at BioMed
Medical Manufacturing Ltd., Sramek developed the apparatus NCCOM3, which
brought significant improvements to the clinical accuracy of the method. In 1992, the
company was renamed to CDIC and the product was called “BioZ”. The bioimpe-
dance measurement of CO (Kubicek et al., 1966; Sramek, 1986) assumes that the
blood ejection within the thorax increases the electrical admittance of the thorax as a
result of changes in the intrathoracic hemodynamic.

The electrical velocimetry model and the cardiometry method
More sophisticated TEB algorithms have since been proposed. In this group, a new model,
the electrical velocimetryt (EVM) (Bernstein et al., 2015), which introduces a new
method named electrical cardiometryt (ECM) (Bernstein and Osypka, 2003; Norozi et al.,