Patent ID: 7209780

Claim:
A system for the determination of quantities relating to the circulatory system of a patient, comprising a device for the non-invasive measurement of the qualitative variation over time of the local concentration of an indicator injected into the blood circulation system at a first position, said measurement taking place at a second position of the blood circulation system and an evaluating unit which comprises an input interface for reading in an input value of the cardiac output COe of the patient, said input interface being connected to a device for measurement of the variation over time of the local blood temperature at a third position of the blood circulation system of the patient after the injection into the blood circulation system at the first position of a bolus which contains the indicator and has a temperature below body temperature, and said device being equipped to determine and provide said input value of the cardiac output COe from the variation over time of the local blood temperature in accordance with methods commonly used fir thermodilution measurements, wherein an evaluating algorithm is implemented in said evaluating unit which transforms the qualitative variation over time of the local concentration of the indicator injected into the blood circulation system into a quantitative variation over time of the local concentration of the indicator injected into the blood circulation system, wherein the condition is fulfilled that the cardiac output COdyc, which is calculable from the quantitative variation over time of the local concentration according to a predetermined relationship, is equal to the input value of the cardiac output COe.