A convenient pulmonary volume and flow detection system

The pulmonary function test (PFT) is a widely used test in patients or for those who are at risk of respiratory dysfunction. In this study, we aimed to develop a more convenient system, namely, the impedance pulmonary function measurement system (IPFS), for overcoming the restrictions posed by the prevalent spirometric PFT. IPFS employs tetra polar electrodes that can measure pulmonary function using the subjects´ hands alone. The impedance measured by IPFS extracts AC values of pulmonary impedance from DC values of body impedance in respiration. This system yields changes in the impedance of volume and flow. In order to verify IPFS, we compared the continuous waveforms obtained from the PFT module and developed IPFS using Pearson linear correlation coefficients (p < 0.01) for volume and flow. Further, we evaluated the potential application of IPFS for detecting pulmonary functions such as volume (FEV1/FVC Ratio) and flow (PEF), and compared the measured parameters between IPFS and spirometric PFT. Our results demonstrate that the measurements obtained using IPFS reflect pulmonary function parameters.