Mapping between ISO/IEEE 11073-10201 Domain Information Model, IHE PCD DEC, and FHIR Resources

Overview of ISO/IEEE 11073-10201 Domain Information Model (11073 DIM) for Point-of-care Devices

Point-of-care devices such as patient monitors, ventilators, anesthesia machines, infusion pumps can present a large number of clinical measurements and device-state variables (in the hundreds) often with complex logical organization, reflecting subsystems of the device and related measurements within each subsystem, in contrast to personal health devices which typically present a small number of measurements and accompanying data that usually have a close logical relationship with each other.

The DIM organizes the data and reflects the logical relationships in an object-oriented hierarchy: the whole device is represented by a Medical Device System (MDS) object, which logically encloses one or more Virtual Medical Devices (VMD). These may be reflections of physical subsystems such as plug-in modules in a patient monitor, or logical subsystems such as the gas-delivery and ventilator functions of an anesthesia machine, or indeed a VMD may model a software component such as a multivariable oxygenation calculator or a software component integrating multiple measurements from other VMDs into a clinical decision support (CDS) risk score.

The DIM also provides for Channels within a Virtual Medical Device, since a VMD may measure multiple instances of a particular kind of measurement, or need to disambiguate between, for example, multiple solution sources in an infusion pump.

The basic unit of data delivery is the Metric object, generally representing a particular measurement or observation kind and associated with a specific code from the ISO/IEEE 11073-10101 Nomenclature, the most comprehensive list and ontology of logical entities, measurement categories, and particular measurements and state variables reported by devices. This standard grows constantly with the development of device technology. The 11073 committees work closely with the LOINC maintainers with the goal of having LOINC cross-mappings available for device-derived clinical observations, but the codes linked to the functioning of the devices themselves have different use models and are outside the scope of other nomenclature systems, so seem likely be the province of only 11073 nomenclature for some time to come.

It is important that the MDS, VMD, Channel, and Metric levels of the 11073 DIM all have their own sets of logically pertinent attributes and nomenclature. For example, when a whole device is powered by a battery, the battery state variables logically belong to the MDS, and so are reported there. As another example, the whole device (MDS), and subsystems like plugin modules (VMDs), may have their own specific identifiers such as manufacturer, model number, and FDA Unique Device Identifier (UDI), and version identifiers for, say, hardware, firmware, and various software components. These are all provided for in the DIM.

Use models for device observation reports and hierarchical versus flattened representation of device data

For charting in a clinical unit, the DIM hierarchy may not need to be visible on an electronic medical record system. Since the device manufacturer or the middleware provider is in control of the modeling of a particular device, an expedient that is sometimes used is to ignore