Research Article

Bioreactance-Based Noninvasive Fluid Responsiveness and Cardiac Output Monitoring: A Pilot Study in Patients with Aneurysmal Subarachnoid Hemorrhage and Literature Review

Figure 1

The NICOM system and its connection to the body. (a) Four double-electrode stickers are placed around the thorax. (b and c) A high-frequency current is passed between the 2 outer electrodes, and the resulting voltages are recorded between the 2 inner electrodes. The relative phase shift (ɸ) and rate of change of phase (dɸ/dt) between these signals are determined and used in the calculations of stroke volume (SV). RF radio frequency (d) schematic representations of aortic flow as a function of time underlying the basic principle for estimation of SV from changes in relative phase shifts (dx/dtmax) and ventricular ejection time (VET).
(a)
(b)
(c)
(d)