Integrate with a Laboratory Information System (LIS) via HL7v2 lab order and result messages

In-depth guide

Steps

1. Establish an MLLP TCP connection between your ordering system and the LIS; define the interface direction (bidirectional is typical: orders flow from ordering system to LIS, results flow from LIS to ordering system) and agree on port assignments and message types with the LIS vendor
2. Send lab orders as ORM^O01 messages: the ORM contains MSH, PID (patient), PV1 (visit), ORC (common order), and OBR (observation request) segments; populate OBR-4 with the ordered test code using the code system agreed with the LIS (often a local code or LOINC)
3. Handle ORM acknowledgments: the LIS responds with an ORR^O02 or plain ACK; check MSA-1 for acceptance and store the filler order number returned in ORC-3 for subsequent result correlation
4. Receive ORU^R01 result messages from the LIS containing OBR (observation request) and OBX (observation result) segments; correlate results to orders using the filler order number in OBR-3 / ORC-3
5. Parse each OBX segment for LOINC code (OBX-3), result value (OBX-5), units (OBX-6), reference range (OBX-7), and abnormal flag (OBX-8); store all fields to support clinical decision support and display
6. Implement order status update handling for ORM cancellations and result corrections (ORU with OBX-11 set to 'C' for corrected); treat corrections as a new authoritative result that supersedes prior values