One system, method and non-transitory computer readable storage medium, for monitoring the perfusion of a patient. System, method and computer readable storage medium receive the instruction for the voltage that one applies in the chest of patient via a first electrode, receive the electric current across the chest of patient, it is measured as caused by applied voltage via a second electrode, generate a respiratory rate waveform based on impedance based on applied voltage and tested electric current, generate a Fourier transformation of the respiratory rate waveform of the heartbeat relative to patient, be isolated in Fourier it is trans- in cardiac artifact and generate one perfusion waveform, it indicates the perfusion in a thoracic cavity of the patient base on the cardiac artifact of isolation.
