Method and arrangements for determining an indicator dilution curve (IDC) of an indicator in a bloodstream of a human or animal body

摘要

A method and an arrangement (50-53) for determining cardiac parameters of a human or animal body (60) having a central bloodstream comprising an indicator periodically passing one or more locations (1) of the body (60). An ultrasound signal is applied (53) to the indicator in the central bloodstream and ultrasound measurements (53) are taken from a return signal in response to the ultrasound signal, of at least a first cycle of the indicator. From the ultrasound measurements (53) an indicator concentration time signal is determined. The indicator is of such a low concentration that there is a descriptive relation between the measurements and the indicator concentration time signal. From the first cycle of the indicator concentration time signal an indicator dilution curve is modelled (50) and the modelled indicator dilution curve is adjusted over a time interval. The time interval corresponds to at least part of the first cycle leading a further cycle of the indicator. Cardiac parameters are determined (50) from a plurality of modelled indicator dilution curves obtained from a plurality of locations in the central bloodstream of the body (60).