HL7 ORB_O28 Blood Product Order Acknowledgment

The response that tells the sender how the blood bank handled an OMB order.
HL7 message structure ORB_O28 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
MSA
 Message Acknowledgment Yes No
ERR
 Error No Yes
SFT
 Software Segment No Yes
NTE
 Notes and Comments No Yes
ORB_O28.RESPONSE
 Response group No No
ORB_O28.PATIENT
 Patient group No No
PID
 Patient Identification Yes No
ORB_O28.ORDER
 Order group No Yes
ORC
 Common Order Yes No
ORB_O28.TIMING
 Timing group No Yes
TQ1
 Timing/Quantity Yes No
TQ2
 Timing/Quantity Relationship No Yes
BPO
 Blood product order No No

ORB_O28 is the acknowledgment response for OMB_O27. It reports whether the blood product order was accepted, rejected, or accepted with returned order identifiers and detail.

This response matters because the blood bank may assign its own order or fulfillment identifiers, reject a request because of missing consent or incompatible detail, or accept the order while downstream preparation continues.

A small ORB O28 example

MSH|^~\&|BLOODBANK|CITYHOSP|EHR|CITYHOSP|20260717123005||ORB^O28^ORB_O28|ORB280001|P|2.5.1 MSA|AA|OMB270001 PID|1||123456^^^CITYHOSP^MR||Smith^Jane^Anne^^Ms^^L ORC|OK|BPORD7001^EHR|BBK8801^BLOODBANK||||||20260717123004 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

What systems do with it

The ordering system uses ORB_O28 to capture the blood bank's response and filler identifier. If the blood bank rejects the order, ERR should point to the missing or invalid detail, such as consent, processing requirement, destination, or clinical indication.

Acceptance does not necessarily mean the product has been dispensed or transfused. It means the order request has been accepted into the receiving workflow. Later blood product status messages may carry dispense or transfusion state.

How to read the structure

The message starts with MSH, MSA, optional ERR, software details, and notes. The optional RESPONSE group can include patient context and order groups. The order group starts with ORC, may include timing, and can carry BPO.

ORC should be read first for acceptance and identifiers. BPO confirms the blood product detail the receiver is acknowledging.

Implementation traps

Do not treat ORB_O28 as proof of issue or administration. Blood product fulfillment has several later operational steps, and those should be represented by the appropriate blood product dispense or transfusion messages when used.

Also avoid throwing away returned order identifiers. Blood bank systems often use their own accession or order number, and it becomes the safest bridge for status and troubleshooting.

Reference notes

The HL7 v2+ ORB_O28 page shows the blood product order acknowledgment with MSA, ERR, an optional response group, patient context, ORC, timing, and BPO detail. Caristix summaries note that OMB uses BPO as the detail segment and ORB as the acknowledgment.