Due to the immense volumes of medical data, the architecture of the future healthcare decision support systems focus more on interoperability than on integration. With the raising need for the creation of unified knowledge base, the federated approach to distributed data warehouses (DWH) is getting increasing attention. In this paper, we explore the idea of a federation technology and its uses within the domain of health, particularly in the conceptualization of DWH federation as a sustainable, appropriate and legitimate solution. Further, we present a federated DWH model which enables the interoperability between heterogeneous and distributed medical IS, which includes a sense and response mechanism and facilitates evidence-based medicine in order to primarily support the physicians at the point of care. A real-world scenario illustrates a possible application field in the area of emergency and intensive care.