Contact person

• Univ.-Prof. Dr.-Ing. Dr. med. Dr. h. c. Steffen Leonhardt

Project description

Today, the monitoring and evaluation of vital functions, especially pulse and breathing rates, are part of the clinical routine. In certain cases (e.g. during dialysis, after a heart attack, or to prevent Sudden Infant Death Syndrome), long-term home monitoring is also necessary. However, the current use of the related ECG-electrodes, PPG-clips or flow sensors is associated with several side-effects like skin irritation, contact problems or large energy requirements. Due to the mechanical work performed by the heart and lungs, well- conducting and poor-conducting fluid volumes (blood or air) pass through the body, which causes a measurable change in the body’s electrical impedance distribution. Through magnetic bioimpedance measurements, which use inductive eddy currents, a non-contact determination of this resistance distribution is possible.

Challenges

• Very small measurement signals
• Signal disturbance sensitive to movements of surrounding metal as well as to movement or deformation of the sensor
• Disturbance to other measuring devices
• Problematic integration

Figure 1 illustrates an early prototype of a single- channel sensor (red), that can be used for the monitoring of heart activity.

Project goals

In the scope of the project , the following goals will be pursued:

• Development of measurement and testing protocols
• Determination of suitable measurement sensors and positions
• Wearable integration in clothing/accessories
• Integration in beds or seating structures
• Non-contact monitoring of premature babies in incubators