Investigation of a bioimpedance-based measurement method of diaphragmatic muscle movements during respiratory characteristics

The diaphragm is the main inhaling muscle, the dysfunction of which can significantly affect hyperinflation of the lungs, the consequence of which can lead to a more severe exacerbation of Chronic Obstructive Pulmonary Disease (COPD). Diaphragm weakness can develop not only in patients with COPD, but also in patients in critical condition who need breathing machine. The diaphragm movement is mostly assessed with techniques that exposes the patient to risks. The bioimpedance measurement is easy to use, safe and measures directly the detection of respiration parameters. Respiratory motion artefacts impair the quality and reliability of bioimpedance measurement, due to the regular occurrence of parameters causing measurement errors such as residual impedance, parasitic capacitance, generator anomalies, and so on. We created an ultra-low frequency, four-electrodes, digital lock-in measurement procedure which fully displays a dispersion across pure, raw data. This pilot study aim to determine whether bioimpedance technique can lead to measure directly the diaphragmatic dome displacement.