An anesthesia device and a process are provided with which a breathing gas, which is present in a breathing circuit and which is especially enriched with an anesthetic, can be removed rapidly and in a cost-effective manner. The breathing circuit comprises an inspiratory breathing gas duct and an expiratory breathing gas duct, for receiving an expired breathing gas, a Y-piece, which is designed as a Y-piece that can be closed, for connecting the inspiratory and expiratory breathing gas ducts with a patient. At least one breathing gas supply system introduces breathing gas into the breathing circuit. A breathing gas outlet duct is provided with a breathing gas outlet valve. A breathing gas reservoir intermediately stores breathing gas. A PEEP valve is arranged upstream of the breathing gas reservoir in the direction of flow of the breathing gas. A breathing gas delivery is arranged downstream of the breathing gas reservoir in the direction of flow of the breathing gas. An air inlet introduces ambient air into the breathing circuit. The air inlet is arranged between the PEEP valve and the breathing gas delivery. A control is provided at least for controlling the ambient air entering through the air inlet, the breathing gas delivery, the PEEP valve and the breathing gas outlet valve for removing breathing gases from the breathing circuit.