Method and apparatus for automatically determining physiological parameters related to human breathing airway resistance and functional residual capacity

Abstract

Abstract METHOD, SYSTEM AND APPARATUS FOR AUTOMATIC DETERMINATION OF PHYSIOLOGICAL RESPIRATORY PARAMETERS RELATED TO HUMAN BREATHING AIRWAY RESISTANCE AND FUNCTIONAL RESIDUAL CAPACITY ARE DISCLOSED. THE PERSON FOR WHOM THE DETERMINATIONS ARE BEING MADE IS SEATED WITHIN A WHOLE BODY PLETHSMOGRAPH (PP) RELATIVE TO ATMOSPHERE BEING SENSED IS LOCATED THEREIN WITH HIM IN A SEQUENCE OF SHORT RAPID BREATHS KNOWN AS PANTING, THE PRESSURE WITHIN THE PLETHYSMIOGRAPH (PP) RELATIVE TO ATMOSPHERE BEING SENSED AFTER A PREDETERMINED NUMBER OF BREATHS AT RESPECTIVE POINTS CORRESPONDING TO PREDETERMINED RESPECTIVE BREATHING AIR FLOW RATES (V) (BOTH INSPIRATORY AND EXPIRATORY POINTS MAY BE USED). THE DIFFERENCE IN PLETHYSMOGRAPH PRESSURE ($PP) AT THESE RESPECTIVE POINTS IS DETERMINED, WHICH IS PROPORTIONAL TO CHANGES IN "BODY VOLUME." THE BREATING FLOW PATH IS THEREAFTER OBSTRUCTED FLOW PATH (PA) SHUTTER, AND THE PRESSURE IN THIS OBSTRUCTED FLOW PATH (PA) RELATIVE TO ATMOSPHERE IS SENSED AT RESPECTIVE POINTS WHEN THE PRESSURE IN THE PLETHYSMOGRAPH CORRESPONDS TO THAT OCCURRING AT THE PREDETERMINED FLOW RATES. THE DIFFERENCE IN PRESSURE ($PA) IN THE OBSTRUCTED FLOW PATH AT THE LATTER RESPECTIVE POINTS IS DETERMINED, THIS DIFFERENCE CORRESPONDING TO INSPIRATORY AND/OR EXPIRATORY AIRWAY RESISTANCE (RAI AND RAE), THE RATIO BETWEEN THESE RESPECTIVE PRESSURE DIFFERENCE INDICATING THE FUNCTIONAL RESIDUAL CAPACITY OF THE PERSON.

Inventors

• 👤 Robert Crane

Bibliographic Details