Introduction of Doppler ultrasound techniques into the Intensive Care setting has revolutionised the way haemodynamic status is monitored in the critically ill. However, in order to increase the usefulness of these techniques, the Doppler signal and its spectrum need to be further analysed in ways to facilitate a better clinical response. Extensive processing of the Doppler spectrum on Diagnostic ultrasound machines is limited by the real time performance considerations. It was therefore proposed that the spectral information from these systems be extracted off-line and full set of analytical tools be made available to evaluate this information. This was achieved by creating an integrated and modular software tool called Spectron, which was intended as an aid in the overall management of the patients. The modular nature of Spectron was intended to ensure that new analytical tools and techniques could be easily added and tested. The software provides its users with considerable latitude in choosing various data acquisition and analysis parameters to suit various clinical situations and patient requirements. Spectron was developed under the Windows environment to provide a user friendly interface and to address a range of programming problems such as memory management and the size of the colour palettes. Spectron is able to detect the maximal velocities and compute the mean and median velocities. Relative increases in maximal velocities in cardiac blood flows after the administration of inotropic drugs have been shown in the pilot studies that were conducted. Spectron is able to help in obtaining estimates of the aortic blood flows and in other applications such measuring vascular impedance. Stenotic blood flows can be detected by using the spectral broadening index and blood flow characteristics can be studied by using various blood flow indices. Thus, this project attempted to help in patient management by providing clinicians with a range of blood flow parameters and has succeeded in meeting its objective to a large extent / Master of Engineering (Hons)