Laboratory Analytical Workflow

Enhanced Laboratory Device Automation

The motivation for developing this enhanced version of LDA is as follows:

Use Cases

Use Case 13: Upload to AM preliminary results generated on LD

Scope: Patient & QC

Purpose: This use case allows to report observations information to the AM as soon as it's available and the internal technical validation rules decide that it is not considered as final observations. Allow AM to report preliminary results (for example to physicians) without waiting final result to be available.

Synopsis: Message sent by the LD in an unsolicited way.

IHE LDA: Not in LDA today.

Messaging Topics

Selection of baseline HL7 version (2.6 or 2.7)

It has influence on data types (CE vs. CWE/CNE, e.g., MSH-19).
It has influence on message structure, e.g. use of UAC segment.

“Enhanced acknowledgment” in addition to the “Original Acknowledgment”

It determines, e.g., cardinality (mandatory) use of MSH-15, MSH-16, ...
The "Original Acknowledgment Mode" of HL7 v2.6 (ch. 2.9.2) required by IHE (see LAB TF-2 ch- 2.4.4) has only one acknowledgment level reporting positive ack, when the application processed it and the storage is guarranteed. However in some scenarios the 2 level acknowledgment with following interpretation of acknowledgments levels 2 and 3 corresponding to the Enhanced Acknowledgment of HL7 v2.6 (ch 2.9.3) could be advantegeous:
- [2] Syntax validated & correct, persistence gurranteed
- [3] Semantics validated, correct and processed by the application for storage in the destination repository (DB with semantically structured information).

Asynchronous message flow (overlapping queries)

This asynchronous message flow will be application for all use cases/messages with the exception of low level ack.

Repeatability of certain fields

“Equipment Instance Identifier” (EQU-1) make repeatable to express nesting  change in HL7 required
“Abnormal flags” (OBX-8) make repeatable as in HL7
“Specimen Description” (SPM-14) make repeatable as in HL7