A system for providing an indication of cardiovascular function, includes a respiration input (1) for receiving a respiration-related signal indicative of a physical property of respiration gases administered to a patient. A hemodynamic input (2) is provided for receiving a hemodynamic-related signal indicative of a hemodynamic property. An inspiration detector (3) is provided for processing the respiration-related signal to detect times of inspiration and a measure of the size of the inspiration. A correlator (5) is provided for correlating the sizes of inspiration with the hemodynamic-related signal, to obtain the indication of cardiovascular function. The respiration-related signal is indicative of inspiration pressure, inspiration volume, or inspiration flow. The hemodynamic-related signal is indicative of blood pressure.