DISTINGUISHING CLOSED AND OPEN RESPIRATORY AIRWAY APNEAS BY COMPLEX ADMITTANCE VALUES

摘要

Methods and apparatus are disclosed for determining the occurrence of a closed or open apnea. Respiratory air flow from a patient is measured to give an air flow signal. The determination of an apnea is performed by applying an oscillatory pressure waveform of known frequency to a patient's airway, calculating a complex quantity representing a patient admittance (12) and comparing its value with ranges (14,16) indicative of open or closed apneas. The method distinguishes open from closed apneas even when the model used to calculate admittance is not based on details of the respiratory apparatus. In addition the patient admittance may be compared with admittance during normal breathing to avoid having to characterize the airway.

主权项

1. A method for determining the occurrence of an apnea comprising measuring respiratory air flow from a patient's airway to provide an air flow signal, applying an oscillatory pressure waveform of known frequency to the patient's airway, calculating a complex quantity representing a patient admittance, and comparing the values of the complex quantity with regions indicative of patency or closed airways.