Modified electrode placements for measurement of hemodynamic parameters using impedance cardiography

Abstract

Measuring and monitoring hemodynamic parameters has brought many benefits in supporting diagnosis and treatment for cardiovascular patients. There are many advantages to measuring hemodynamic parameters by non-invasive technique based on impedance cardiography (ICG) such as simplicity, real-time and low cost. However, the electrode positions of this method are very difficult to implement in cases where the patient has to use multiple medical devices at the same time, especially for patients on active treatment and resuscitation. This paper presents the results of the study proposing new three locations of ICG electrodes to overcome the above limitation. Accordingly, we measured and evaluated 10 volunteers on the Niccomo device. The results show that all three positions of proposed electrode can be used to replace standard electrode position. In particular, the 1st proposed position, can be used to measure all five hemodynamic parameters HR, SV, LVET, Z_o, CO and ICG waveforms, expressed by the average correlation and the relative average difference of five parameters, $\overline{R^2}$ = 0.9641 and $\overline{\mathrm{Mean}}$ = 3.31%. The 2nd proposed position can be used to measure four parameters HR, SV, LVET, CO and ICG waveforms shown by $\overline{R^2}$ = 0.9091 and $\overline{\mathrm{Mean}}$ = 8.67%. The 3rd proposed position can be used to measure three parameters HR, Z_o and LVET, expressed by $\overline{R^2}$ = 0.8485 and $\overline{\mathrm{Mean}}$ = 9.26%.

Keywords: Impedance cardiography; cardiac output; electrode placement; hemodynamic parameters; stroke volume.