Objective: Systems designed for medical device integration often suffer from a limited set of supported devices. Justified by resource and mobility constraints, integration systems like smart phones or gateways are restricted with regard to the set of device control and data aggregation logic deployable. This contradicts the requirements of patients and physicians in terms of vendor-independence and adaptability of the system. Often a large variety of medical devices needs to be considered to provide a meaningful survey of a patient's condition. Moreover, especially in case of emergencies, the set of required devices is often changing rapidly.

Method: Physical integration and spontaneous interoperability are core aspects of open and modular device integration solutions. Therefore, we first introduce the OSGi Device Access Specification as a technical foundation to our approach. Furthermore, we discuss an external representation of device descriptions and the impact of semantic interoperability with regard to the e-Health domain. Based on these findings, the architecture is introduced and described with respect to its components and behavior.

Results: As a mitigation to the problem of medical device integration, we present a middleware platform that is able to adapt itself to the requirements of patients and Care Delivery Operators. Based on a modular design, medical devices can be integrated on-demand. The middleware is composed of a device integration and a data aggregation layer. The aggregation layer allows transforming heterogeneous data streams according to the demands of the respective clinical information system. Both layers utilize external knowledge repositories to deploy currently required device control and data aggregation logic at runtime. A proof of concept is given by a prototype developed for a tele-rehabilitation project.

Conclusion: Based on a proof of concept prototype developed for a tele-rehabilitation project, we show that a modular and open medical device integration middleware can be developed on top of existing industry standards like OSGi. The presented approach allows Care delivery Operators to integrate semantically aligned medical data streams into their information systems without requiring to reconfigure their integration systems.