Monitoring respiratory parameters as a health status indicator

This paper describes an ongoing effort aimed at exploring the use of respiratory parameters to assess the condition of the lungs and heart. These parameters will be measured with a novel noninvasive technique, the Quick Obstruction Method. The method measures respiratory parameters by creating a short duration, partial obstruction of the respiratory airflow during normal breathing (inspiration), while recording flow and mouth pressure. The specific parameter expected to contain relevant information about heart function is respiratory inertance, a parameter indicative of inertivetype effects manifested when flow rate is quickly increased or decreased. These inertivetype effects are found in: a) air in the airways, and b) respiratory apparatus (lung tissues, abdomen, chest wall, etc.). A patient experiencing heart failure (indicated by low ejection fraction as measured with the echo cardiogram), is expected to have lungs that are partially filled with fluid. We expect that the excess of fluid will be correlated to an increased respiratory inertance.