Ricerc@Sapienza

In this paper, the design and characterization of a device, able to analyze the electrical bio-impedance in the frequency domain and its variations with time, is presented. The whole system design, that employs a tetra-polar electrode configuration, a specifically developed printed circuit board, and a data acquisition card connected to a PC, is presented. The measurement system is controlled through LabVIEW virtual instruments.

Impedance plethysmography is a technique which allows the monitoring of respiratory activity through the measurement of variations in the trans-thoracic impedance. Provided the measurement system has enough sensitivity, the same technique can also detect heartbeats, thus adding cardiac activity monitoring capabilities. In this paper, a comparison is performed between 2-electrode and 4-electrode systems, considering both volt-amperometric and AC-bridge solutions.

In this paper, the design and characterization of a device, able to analyze the electrical bio-impedance in the frequency domain and its variations with time, is presented. The whole system design, that employs a tetra-polar electrode configuration, a specifically developed printed circuit board, and a data acquisition card connected to a PC, is presented. The measurement system is controlled through LabVIEW virtual instruments.

Impedance plethysmography is a technique that allows monitoring changes in the volume of specific tissues or organs inside the human body, through the measurement of variations in the bio-impedance between electrodes placed on the body surface. One of its best-known applications is the monitoring of respiratory activity based on trans-thoracic impedance measurements. Provided the measurement system has enough sensitivity, trans-thoracic impedance can also allow the detection of heartbeats, thus adding cardiac activity monitoring capabilities.