PIX Query

A PIX query is triggered when one of the domains in the PIX/PDQ system requests a list of patient identifiers that are associated with a specific patient identifier. This request is processed by the Master Index, which responds with a list of associated patient identifiers if any exist.

PIX Query Processing Flow

PIX queries are processed as follows. This can be seen in the figure Figure 1.

1. A request is sent by an HL7 messaging domain for any identifiers associated with the given patient identifiers.

2. The message is received by the HL7 Binding Component if it is HL7 v2, or by the HTTP Binding Component if it is HL7 v3.

3. The message processed through the Normalized Message Router (NMR) to one of the following BPEL processes, depending on which version of HL7 is being processed: IHEPixPdqV2BpelProcess (v2) or bpelPIXManager (v3).

4. The BPEL process maps the data and routes it to the MDM Facade EJB, which then sends it to the Master Index for processing.

5. The Master Index cross references the given patient identifier against existing information in the master index database, and either returns a list of identifiers or null, if none were found.

6. The BPEL process then sends the list of identifiers back through the NMR and Binding Components to the originating domain, and generates an ACK or NACK response, which is also sent back out to the originating domain.

7. The BPEL process generates the audit record of the transaction, which is stored in the ATNA repository.

PIX Query HL7 Message Types

In the HL7 v2 IHE framework, this type of event is known as an ITI-9 transaction. It is triggered by the following HL7 v2 event, and is identified as a “Query” event with an event ID of 110112:

• Q23: Get corresponding identifiers

The master patient index response to the Q23 request is the following HL7 v2 event:

• K23: Corresponding patient identifiers

In the HL7 v3 IHE framework, this type of event is known as an ITI-45 transaction. It is triggered by the following HL7 v3 event. For audit purposes, it is identified as a “Query” event with an event ID of 110112.

• PRPA_TE201309UV02: Patient registry get identifiers query (triggers a PRPA_IN201309UV02 message)

The master patient index response to the above request is the following HL7 v3 event:

• PRPA_IN201310UV02: Patient registry get identifiers query response