Monitor for automatic resuscitator with primary and secondary gas flow control

摘要

The present invention pertains generally to a monitoring system for a resuscitator which detects operation of the resuscitator and a controller unit for a supply of therapeutic gas to a resuscitator, and more specifically, a flow controller for a supply a therapeutic gas to an automatic resuscitator which is triggered by a single point pressure signal provided by the cycling of the automatic resuscitator from a controlled inhalation phase to a controlled exhalation phase. The monitoring aspect of the system detects single point low pressure signals which are sequentially compared against a time clock. Failure of the resuscitator system itself to generate a low pressure signal against the integrated time clock causes an alarm condition. Further, gas management is effected by a flow controller integrated into the monitor, a gas management system which responds to the single point low pressure signal and operate a primary gas control valve attached between a gas supply and an automatic resuscitator such that gas is allowed to flow to the resuscitator when the resuscitator is in an inhalation mode and gas flow is interrupted when the resuscitator is in an exhalation mode. A secondary gas control valve is integrated into the gas management system in parallel to the primary gas control valve. The flow controller includes a low threshold pressure sensor which is actuated by means of a recurrent low pressure pulse generated by the automatic resuscitator itself through the cycling of the resuscitator and remains essentially unaffected by the respiratory cycling of the patient, thus preventing false triggers and greatly simplifying the flow controller operation and format. The low threshold pressure sensor is coupled to a processor wherein the processor reads the occurrence of a pressure event at the pressure sensor and which then closes the primary gas control valve and starts a clock. As the pressure is decreased in the gas management system resulting from the primary gas control being moved to a closed position, the secondary gas control valve moves to open state, thus allowing the gas management system to vent to atmosphere during exhalation, reducing the pressure of the system to an operator defined positive level. Once the clock reaches a pre-defined duration, the primary gas control valve is reopened, the pressure in the gas management system increases thus closing the secondary gas control valve, the automatic resuscitator continues into an inhalation mode, and the process repeats.