ventilator safety valve

A lung ventilator safety valve apparatus for relieving pressure in a patient airway of a ventilator system, comprising:

• a safety valve connected to a patient airway of a ventilator system, said safety valve having a normally closed position and an open position venting pressure from said patient airway;
• a pressure sensor means connected to said patient airway for monitoring pressure in said patient airway and for generating a pressure signal indicative of sensed pressure in said patient airway;
• a time monitor means connected to pressure sensor means for monitoring time that pressure is elevated in the airway above maximum pressure threshold as measured by pressure sensor
• a valve control means connected to said safety valve for controlling operation of said safety valve, and connected to said pressure sensor means for receiving said pressure signal and to said time monitor means for receiving time signal, and having means for setting a maximum airway pressure threshold and a maximum time threshold of elevated inspiratory pressures, a means for comparing said sensed pressure and said monitored time in said patient airway with said maximum airway pressure and time threshold, and means for generating a valve open signal when said sensed pressure and time in said patient airway is equal to or greater than said maximum airway pressure and said maximum time
• a valve switching means connected to said valve control means for receiving said valve open signal for switching said safety valve to said open position in response to said valve open signal.