BOXLESS MEASUREMENT OF THORACIC GAS VOLUME

摘要

This invention is a portable apparatus for measuring the thoracic lung volume of a patient without enclosing the patient in a sealed chamber, comprising first (12) and second (14) impedance belts, a flow meter (10), shutter (22), and a microprocessor based controller (16). The flow meter includes pressure transducers (42, 44) for measuring the change in volume and pressure as the patient respires therethrough. The change in thoracic cage volume of the patient's lungs is directly correlated with the change of impedance in the belts. The thoracic lung volume is then determined from a measured barometric pressure, the measured change in pressure and the measured volume change in the thoracic cage volume utilizing a correction factor to determine the thoracic cage volume.