Reliability-enhanced apparatus operation for re-breathing and methods of effecting same

2 2 2 2 2 An apparatus and method for affording a re-breathing capability to a breathing circuit. The apparatus includes a valve that permits air flow through or re-breathing in the breathing circuit. A COsensor and an air flow sensor detects COa rate of air flow in the breathing circuit, respectively. A processor computes a parameter based on the COwaveform feature and a volumetric COwaveform feature based on signals from the air flow sensor and/or the COsensor. An alarm is triggered when the parameter deviates from a selected magnitude. In a further embodiment, at least one parameter associated with an energy source for actuating the valve is monitored. Deviation of the value from at least one selected value of the at least one parameter is corrected.