Dynamic bio impedance range adjustment for a medical device

This disclosure is directed to devices, systems, and techniques for dynamically adjusting a bio impedance measurement range. An example device includes a plurality of electrodes. The device also includes sensing circuitry configured to sense a bio impedance and processing circuitry. The processing circuitry is configured to apply an excitation signal to the sensing circuitry and, based on the application of the excitation signal, determine a sensed bio impedance value within a bio impedance measurement range. The processing circuitry is also configured to determine whether the sensed bio impedance value is within a predetermined portion of the bio impedance measurement range for a predetermined period of time and based on the sensed bio impedance value being within the predetermined portion of the bio impedance measurement range for the predetermined period of time, adjust the excitation signal.