Create an HL7v2 ORM^O01 lab order message for an outbound order interface

In-depth guide

Steps

1. Build the MSH segment with correct sending and receiving application/facility names, current timestamp in MSH-7, message type ORM^O01 in MSH-9, a unique message control ID in MSH-10, and version 2.5.1 or 2.3.1 as agreed with the receiving LIS
2. Construct the PID segment with the patient's internal MRN in PID-3, full name (family^given^middle) in PID-5, date of birth in PID-7, gender in PID-8, and address in PID-11; omit SSN from PID-19 unless explicitly required by the interface specification
3. Add a PV1 segment for the patient's current visit context including patient class (I for inpatient, O for outpatient, E for emergency), attending physician NPI and name in PV1-7, and visit number in PV1-19
4. Build the ORC segment with order control code NW (new order) in ORC-1, a unique placer order number in ORC-2, order status, ordering provider NPI and name in ORC-12, and the order effective date/time
5. Construct the OBR segment with the placer order number matching ORC-2 in OBR-2, the ordered test identifier in OBR-4 (local code or LOINC as agreed), specimen collection date/time in OBR-7, and any clinical notes in OBR-13
6. Add NTE segments after OBR for any free-text clinical notes relevant to the order, and include DG1 segments for diagnosis codes if required by the LIS to support test ordering rules or insurance billing