HL7 Message Processing


Message Processing simply means:

1. What do we do with the HL7 messages we receive?
2. How do we create HL7 messages that we need to send?

 Answering these two questions properly (and completely) is the actual real work that goes into creating any HL7 interface, so planning is very important. 

First - Identify your trading partner(s). With whom are you exchanging HL7 and what are their data requirements / capabilities. A simple scenario for consuming HL7 messages:

ScenarioIf YOU are an EMR and you want a Practice Management System to forward Lab Result HL7 messages that they receive on to you, first you have to know "Can they do that?". If the answer is NO then you have to work out the issues by either:

A) Having the PMS change their system to export Lab Results OR
B) Negotiate directly with the LAB to see if they can send two identical HL7 feeds (1 for each of you) OR
C) Changing the whole thing around so that YOU receive the Lab Result HL7 feed first and then YOU forward it on to the PMS

None of these answers is more right or more wrong than the other. This is why you always remember that every HL7 interface is always a negotiation. Many times it may not be a question of capability but rather of cost IE the PMS is ABLE to forward the Lab Result HL7 on to your EMR but their cost for doing it is unbearable. It is in scenarios like this where our UltraPort HL7 Postmaster can be invaluable to you. That software specializes in taking 1 inbound HL7 feed and intelligently delivering it to multiple destinations.


Second - Obtain HL7 Interface specifications from your trading partner(s). If you are RECEIVING HL7 messages from a trading partner then you want to ask them for their SampleHL7SpecOUTBOUND HL7 Interface specification. Their OUTBOUND specification should tell you things like: What HL7 version is used, which types of HL7 messages they will send, which HL7 segments those messages will contain including required, conditional, repeating conditions for the data fields in those segments.

If you are SENDING HL7 messages out to a trading partner you will want to ask them for their INBOUND HL7 interface specification which should detail which types of HL7 messages they accept and what data they require, pretty much the same thing as an inbound specification. If you'll have a look at the image embedded in this section it is a snippet of the introduction of a real HL7 interface document which is done properly.

ImportantIMPORTANT. Remember that you will also be expected to have these types of documents for your own HL7 interfaces. Whether you create these documents before you begin the actual work of developing your interface or wait until you've completed it is your own decision. Creating them during the planning phase might make it easier since you can then use the document(s) to help guide the process.


BlueLeftArrow32 Back To: Sending HL7 Next Article: Consuming HL7 BlueRightArrow32