HL7 OMB_O27 Blood Product Order

The order message for blood products, processing requirements, and transfusion-related context.
HL7 message structure OMB_O27 groups and segments from HL7 v2.5.1 Hide structure

These are the generated groups and segments for the version selected at the top of the page. The article explains the workflow, and this panel follows the chosen HL7 version.

Message Structure

SegmentNameRequiredRepeatable
MSH
 Message Header Yes No
SFT
 Software Segment No Yes
NTE
 Notes and Comments No Yes
OMB_O27.PATIENT
 Patient group No No
PID
 Patient Identification Yes No
PD1
 Patient Additional Demographic No No
NTE
 Notes and Comments No Yes
OMB_O27.PATIENT_VISIT
 Patient Visit group No No
PV1
 Patient Visit Yes No
PV2
 Patient Visit - Additional Information No No
OMB_O27.INSURANCE
 Insurance group No Yes
IN1
 Insurance Yes No
IN2
 Insurance Additional Information No No
IN3
 Insurance Additional Information, Certification No No
GT1
 Guarantor No No
AL1
 Patient Allergy Information No Yes
OMB_O27.ORDER
 Order group Yes Yes
ORC
 Common Order Yes No
OMB_O27.TIMING
 Timing group No Yes
TQ1
 Timing/Quantity Yes No
TQ2
 Timing/Quantity Relationship No Yes
BPO
 Blood product order Yes No
SPM
 Specimen No No
NTE
 Notes and Comments No Yes
DG1
 Diagnosis No Yes
OMB_O27.OBSERVATION
 Observation group No Yes
OBX
 Observation/Result Yes No
NTE
 Notes and Comments No Yes
FT1
 Financial Transaction No Yes
BLG
 Billing No No

OMB_O27 is the blood product order message. It exists because blood product orders need detail that ordinary order messages do not capture well: component type, processing requirements, amount, intended use, dispense timing, destination, indication, and consent.

This is a high-consequence workflow. A blood product order is not just another supply request. The receiving blood bank or transfusion service needs enough structured detail to assess appropriateness, prepare the right component, and route it safely.

A small OMB O27 example

MSH|^~\&|EHR|CITYHOSP|BLOODBANK|CITYHOSP|20260717123000||OMB^O27^OMB_O27|OMB270001|P|2.5.1 PID|1||123456^^^CITYHOSP^MR||Smith^Jane^Anne^^Ms^^L||19800314|F PV1|1|I|WARD3^312^A^CITYHOSP ORC|NW|BPORD7001^EHR||||||20260717123000|||12345^Careful^Clara TQ1|1||||||20260717150000 BPO|1|RBC^Red blood cells^L|IRR^Irradiated^HL70508~LR^Leukoreduced^HL70508|2|600|mL^milliliter^ISO+|20260717150000|BLOODBANK^^^CITYHOSP|||20260717143000|WARD3^312^A^CITYHOSP||ANEMIA^Symptomatic anemia^L|Y SPM|1|SPEC7001^EHR||BLD^Blood^HL70487 DG1|1||D64.9^Anemia unspecified^I10 OBX|1|NM|718-7^Hemoglobin^LN||6.8|g/dL|12.0-16.0|L|||F BLG|WARD3^Ward cost center^L

What workflow it represents

The sender is usually an EHR, order entry system, transfusion module, or integration engine. The receiver is usually the blood bank, transfusion service, or lab system responsible for reviewing and fulfilling the product order. The response is commonly ORB_O28.

The receiver uses BPO to understand the product and requirements, DG1 and OBX for clinical context, and SPM when specimen context is relevant.

How to read the structure

The optional patient group is the usual PID/PV1/insurance/allergy context. The required ORDER group starts with ORC, can include timing, and then requires BPO. It can also include specimen, notes, diagnoses, observations, financial transactions, and billing.

BPO is the center of the message. Use it for blood product component, processing requirements, quantity, requested dispense time and destination, indication for use, and consent indicator. Keep that data structured; free text should support the order, not replace it.

Implementation traps

Do not map processing requirements as casual notes. Irradiated, leukoreduced, CMV-negative, washed, and similar requirements change what is prepared and issued. They need explicit codes both systems understand.

Also separate clinical indication from delivery logistics. The reason for transfusion and the location where the product should be dispensed are different decisions and belong in different fields.

Reference notes

The HL7 v2+ OMB_O27 page says blood product orders need additional detail beyond standard order messages, including component, special processing, amount, and relevant clinical information for prospective review.