An apparatus for medical fluid delivery is to be improved for the sake of simple monitoring of the quantity of medical fluid delivered. For attaining this object, a safety device (15) with a patient model (16) is provided, which from past values and current values of the dosage rate of the medical fluid extrapolates a future medical fluid concentration (17) and switches off the dosage unit (10) for the medical fluid if the extrapolated medical fluid concentration (17) exceeds a predetermined limit value (14).