Standard Device
The Standard HL7 to CDA device converts ORU and MDM HL7 messages to CDA (for Catalyst ingestion). This device has been designed to cover cases where only the Root OID, Patient Issuer OID, Exam Issuer OID, and CDA Type need to be configured. Conversion to CDA will be handled by the device using predefined logic.
The standard device assumes that all variables will be set on a per-feed basis. Ie, the root OID, Patient Issuer OID, Exam Issuer OID, and CDA Type are fixed for each channel. If you are receiving a feed which contains multiple issuers or CDA Types, you will either need to branch the feed to multiple channels, or use the advanced HL7 to CDA device.
This device currently supports the following CDA types:
ORU Narrative
ORU Lab
MDM
If you need to specify variable OIDs, or provide your own logic for generating the CDA, you need to use the Advanced HL7 to CDA device.
Background: How does the device work?
Both the standard and advanced devices use three components. These components are hidden in the standard device and exposed in the advanced device.
Templates: These are text files containing the target CDA document with the variable pieces replaced by 'tags' (We use Microsoft's Razor format from ASP.NET). When the device runs, it replaces each 'tag' with the proper value. These documents also support embedded C# and VB statements. The standard device contains two templates: ORU and MDM.
Template Contexts: These are classes which specify which values will be injected into the templates. There is one for each type of CDA: ORU Narrative, ORU Lab, and MDM.
Content Converters: These are classes which convert OBX-5 to structured content.
When the device runs, it combines each component to produce the CDA document.
The current version of the HL7 to CDA device only supports textual OBX-5 content. Support for other input formats such as RTF, and other output formats such as HTML may be added in the future.
Configuration
Configuring the standard HL7 to CDA device is very simple. Enter the Root OID and select the correct CDA Type. For Patient and Exam Issuer, enter the OID Fragment and a corresponding description. The OID fragment is combined with the root OID to produce the full OID value. Typically, Patient OID = RootOID + "." + Patient OID Fragment + "." + MRN, and Exam OID = RootOID + "." + Exam IssuerID + "." + Accession.
Previewing Conversion Results
The HL7 to CDA device provides a real-time view of the resulting CDA document if you have an HL7 message selected in a preceding queue device. You can also paste an HL7 message into the Inbound Message viewer. Note that the Outbound Message viewer can be dragged out of the client application and resized to show the entire CDA document.
ORU Processing
The default logic for processing ORU messages creates one CDA document per OBR segment. For HL7 messages which create multiple CDA documents, a summary message is displayed in the outbound viewer listing the number and document IDs of the generated CDA documents.