Abstract: A reinhalation system for an anesthetic apparatus includes exhalation and inhalation branches which are directly connected to each other. The inhalation branch comprises a dosing unit capable of supplying a component to said inhalation branch. A control unit controls the dosing unit. A first concentration measuring device measuring the concentration of the component and a flow meter measuring a flow rate of a fluid are provided. The dosing unit supplies at least the component to the inhalation branch at a dosing point located downstream of the first concentration meter. The control unit controls the supply of the component as a function of the concentration of the component measured by the concentration meter and the flow rate of the fluid measured by the flow meter.