Method and an apparatus for monitoring and controlling flows

摘要

A method and an apparatus for monitoring and controlling flows in medical equipment including an anesthetic machine and a ventilator for influencing a patient's respiratory system are disclosed. The apparatus comprises a microprocessor and an airway system comprising drive gas conduits provided with an inhalation valve ( 2 ) and an exhalation valve ( 5 ) for gas discharging as well as a ventilator end flow sensor ( 3 ) for measuring the introduced or discharged drive gas flow through the valves. The airway system also comprises patient end breathing tubing in which a patient end flow sensor ( 11 ) for measuring the patient's inspired and expired gas flow is provided. By comparing the measured values of the two flow sensors against the characteristic curve of the inhalation valve ( 2 ), the microprocessor can judge the operation states and accuracy of the respective flow sensors and the inhalation valve ( 2 ).