Patent ID: 6537228
Filing Date: 2003-03-25
Classification: A61B

Abstract:
An apnea monitor comprising:a signal processor which receives an impedance pneumography signal and a heart rate signal from a patient and measures an amplitude excursion between a first inflection point and a second inflection point of said impedance pneumography signal; a threshold detector which classifies said excursion as a first type if it exceeds a first, lower threshold or as a second type if it exceeds a second, higher threshold and discards said excursion if it is below said first threshold; a timer which measures a time interval from said first inflection point to said second inflection point; a comparator which compares said time interval to a period of said heart rate signal; and a discriminator which rejects said first and second inflection points when the time interval is within a preselected range; and an identifier which identifies said second inflection point as a respiratory event if said time interval is outside of said preselected range or said excursion is of said second type.