Requirements specification for apps in medical application platforms

Existing regulatory agency guidance documents and process standards for medical devices (i.e., IEC 62304) generally consider medical devices to be stand-alone monolithic systems. The format and content of a system requirements document largely follows that of conventional embedded safety-critical systems. However, a vision is emerging of a new paradigm of medical system based on the notion of a medical application platform (MAP). A MAP is a safety- and security-critical real-time computing platform for (a) integrating heterogeneous devices, medical IT systems, and information displays via a communication infrastructure and (b) hosting application programs (i.e., apps) that provide medical utility via the ability to both acquire information from and update/control integrated devices, IT systems, and displays. To ensure a regulatory pathway for MAPs, it is necessary to adapt traditional development processes and artifacts to the specific characteristics of MAP architectures and constituent components. In this paper, we provide an initial proposal for developing and formatting requirements for MAP apps. For illustration, we consider an app that implements two “smart alarms” for pulse oximetry monitoring in a clinical context.