By Arleen Thukral, MS, CCE, CHTM

It’s well-known that medical devices provide clinicians with real-time statuses of patients’ conditions, including their vital signs—data that is critical for treatment and, subsequently, patient safety. When archived appropriately and used for retrospective studies, the data has the potential for insights into the progression of disease and treatment that help with assessing the quality of overall care.

The clinical information system (CIS) or electronic health record (EMR) is the user interface where the clinician and other hospital personnel interact with this data. Delays, inaccuracies, or transcription errors may have severe, adverse consequences, however, including misdiagnosis or a potential for harm including patient mortality. Since manual transcription and patient data entry can lead to such issues, hospitals are implementing medical device integrations.

Device Data Transfer

Virtually every medical device made in the last 20-plus years meets a basic connectivity requirement in that it outputs data in a machine-readable format. The physical transfer of data happens over a wired or wireless network connection, or perhaps a serial data connection, which transfers bytes from the source to the receiving information system.

Note: The clinical device data format must be decoded and imported into the receiving systems. Typically, a vendor-provided software component (aka: a device driver) decodes and translates it, providing a clinically usable metric with clinical context (i.e, a time stamp, the clinical measurement, the units of measure, the patient, or the location of the data source) for clinical presentation and storage.

Moreover, the systems that acquire serial data, parse it, and convert it to a network connection are called medical device data systems, or MDDS. (Key vendors in this space are Bernoulli Health; Qualcomm Life; and Cerner, which offers CareAware.) Traditionally speaking, MDDS’ have been wired systems requiring network cabling and power.

In many other cases, a device gateway transfers the data. These are usually servers or central-station computers that collate and consolidate the data-streams from several medical devices—typically, patient bedside monitors or infusion pumps. These gateways then forward the filtered and collated data to the CIS to be presented at the clinical user interface. The user then reviews the acquired data (referred to as “validation”) before storage. The medical device proprietary protocol can also be converted to Health Language-7 (HL7) and sent to the CIS.

Top Integration Challenges

Many EMR vendors will require device patient association steps to ensure accurate patient mapping. In other words, when a new patient is connected to a medical device, the device transmits that patient’s physiological data, rather than the data of the previously attached patient. When there is no connectivity feature, it won’t establish patient context; consequently, any patient context workflow becomes “extra work.”

Since connectivity is supposed to provide workflow automation, users of connectivity solutions base their product evaluations on the new solution’s ease of use and whether or not it takes fewer, the same, or more steps when compared to the previous iteration of the device. Poor usability and/or extra workflow steps can spell poor user acceptance…or outright rejection.

Another challenge is that hospitals lack medical device standardization and have hundreds of different devices and equipment models that they want to integrate. And many of these devices cannot send their data in a format or frequency that the CIS or EMR can receive.

Moreover, once a customer sale is made that includes clinical documentation, the medical device and EMR vendors exchange HL7 interface specification documents; technicians from each company review the other’s specification documents and discuss how each side of the interface can be configured to a working interface. A test fixture is then configured and tested. Once a working configuration is validated (through verification testing), the configuration file is used to deploy in the production environment. This process is repeated with each sale, and each new hospital requires professional service hours for validation testing.

Since the HL7 standard was built (mostly by vendors) to include many options and exceptions, it is not plug-and-play. Consequently, there are many ways to configure on-side of an interface, which are all consistent with the standard. In addition, like any other software business, EMR vendors regularly come out with new versions or releases.

There is no general tendency among hospitals to keep up with vendors and employ the latest software release. Subsequently, even if two or more customers have the same EMR vendor and product, they seldom run the same release. This means that HL7 interfaces in each hospital may have to be configured differently since hospitals run different versions of the same application.

Over the past several years, the clinical engineering and informatics communities have come together to try to develop a set of standards for device vendors to follow so that all devices will be able to transmit data to the CIS and make devices and systems interoperable. Fast Healthcare Interoperability Resources, or FHIR, is a new flavor of HL7 that is intended to be easier to implement and maintain and facilitates cloud-based integration platforms based on proprietary application programming interfaces, such as Redox and Sansoro Health.

Look forward to another Networking article discussing FHIR in greater detail. In the meantime, clinical engineering should steward human factors engineering and quality workflow automations while testing medical device integrations.

Arleen Thukral, MS, CCE, CHTM is a VISN 20 biomedical engineer at VA NorthWest Healthcare Network in Seattle. For more information, contact 24×7 Magazine chief editor Keri Forsythe-Stephens at [email protected].


  • Rhoads, J. G., et al. (2010). Medical device interoperability and the Integrating the Healthcare Enterprise (IHE) Initiative. IT Horizons.