Message type

General order message with document payload

Submits a general order with an attached document payload. The ORC and OBR segments define the order, with additional segments carrying the document content.

52segments

15required

5groups

v2.9HL7 version

# Zato
from zato.hl7v2 import HL7Message

# An incoming message ..
raw = 'MSH|^~\&|SENDER|FAC|RCV|DEST|20260701||' \
      'OMQ^O57^OMQ_O57|MSG001|P|2.9\r' \
      'ORC|NW|ORD001||GRP001|||1^BID\r' \
      'OBR|1||ORD001'

# .. parsed into a Python object ..
msg = HL7Message.parse(raw)

# .. whose fields we can now access.
order_control = msg.orc.order_control
order_number = msg.orc.placer_order_number
order_id = msg.obr.placer_order_number
test = msg.obr.universal_service_identifier

Python examples

Build and parse OMQ^O57 messages in Python

How to construct, send, receive, and extract fields from real-world OMQ^O57 messages.

Parse an incoming OMQ^O57 message

Demonstrates receiving and extracting key fields from a general order message with document payload transaction

# Zato
from zato.hl7v2 import HL7Message

# An incoming message ..
raw = 'MSH|^~\&|SENDER|FAC|RCV|DEST|20260701||' \
      'OMQ^O57^OMQ_O57|MSG001|P|2.9\r' \
      'ORC|NW|ORD001||GRP001|||1^BID\r' \
      'OBR|1||ORD001'

# .. parsed into a Python object ..
msg = HL7Message.parse(raw)

# .. whose fields we can now access.
order_control = msg.orc.order_control
order_number = msg.orc.placer_order_number
order_id = msg.obr.placer_order_number
test = msg.obr.universal_service_identifier

Tutorials

Learn by building

Step-by-step guides for working with HL7 v2 in Zato.

MLLP

Receive and parse HL7 v2 messages

Set up an MLLP channel, parse incoming messages, and respond with acknowledgments.

Start tutorial Build

Build and send HL7 v2 messages

Construct HL7 v2 messages from scratch using typed segment classes and send them over MLLP.

Start tutorial

FAQ

Frequently asked questions

Use the HL7v2 message parser to extract the typed structure. The parsed message gives you direct access to every segment and field by name.

from zato.hl7v2 import HL7Message

raw = 'MSH|^~\&|SENDER|FACILITY|RECEIVER|DEST|20260401120000||OMQ^O57^OMQ_O57|MSG00001|P|2.9'
msg = HL7Message.parse(raw)

order_control = msg.orc.order_control
order_number = msg.orc.placer_order_number

Beyond the mandatory MSH header, the required segments are: PID, PV1, IN1, ORC, OBX, TXA, OBX, PID. Optional segments provide additional detail when available.

Zato connects to any system that speaks HL7v2 over MLLP or FHIR over REST. This includes Epic, Cerner, Meditech, Allscripts, and other EHR platforms.

Yes, Zato has built-in MLLP support for sending and receiving HL7v2 messages. MLLP channels handle the framing protocol automatically.

Zato supports HL7 v2.9, which is backward compatible with earlier versions including v2.3, v2.5, and v2.7. Standard segments and datatypes are available as typed Python classes.

Yes. Zato handles both HL7v2 and FHIR natively, so you can parse v2 messages and build FHIR resources with IG-specific extensions in the same service. Typed Python classes are available for both protocols, including extensions from US Core, UK Core, Da Vinci, and other Implementation Guides.

Reference

OMQ^O57 segment composition

Segments that make up the OMQ^O57 message, in order. Groups are shown with their child segments.

#	Segment	Usage	Repeats	Description	Group
1	`MSH`	Required	No	Message header	-
2	`ARV`	Optional	Yes	Access restriction	-
3	`SFT`	Optional	Yes	Software segment	-
4	`UAC`	Optional	No	User authentication credential	-
5	`NTE`	Optional	Yes	Notes and comments	-
6	`PID`	Required	No	Patient identification	PATIENT
7	`PD1`	Optional	No	Patient additional demographic	PATIENT
8	`PRT`	Optional	Yes	Participation information	PATIENT
9	`NTE`	Optional	Yes	Notes and comments	PATIENT
10	`NK1`	Optional	Yes	Next of kin / associated parties	PATIENT
11	`ARV`	Optional	Yes	Access restriction	PATIENT
12	`PV1`	Required	No	Patient visit	PATIENT
13	`PV2`	Optional	No	Patient visit - additional info	PATIENT
14	`PRT`	Optional	Yes	Participation information	PATIENT
15	`IN1`	Required	No	Insurance	PATIENT
16	`IN2`	Optional	No	Insurance additional info	PATIENT
17	`IN3`	Optional	No	Insurance additional info - certification	PATIENT
18	`GT1`	Optional	No	Guarantor	PATIENT
19	`AL1`	Optional	Yes	Patient allergy information	PATIENT
20	`ORC`	Required	No	Common order	ORDER
21	`PRT`	Optional	Yes	Participation information	ORDER
22	`OBX`	Required	No	Observation result	ORDER
23	`PRT`	Optional	Yes	Participation information	ORDER
24	`TXA`	Required	No	Transcription document header	ORDER
25	`CTD`	Optional	No	Contact data	ORDER
26	`DG1`	Optional	Yes	Diagnosis	ORDER
27	`OBX`	Required	No	Observation result	ORDER
28	`PRT`	Optional	Yes	Participation information	ORDER
29	`NTE`	Optional	Yes	Notes and comments	ORDER
30	`PID`	Required	No	Patient identification	PATIENT_PRIOR
31	`PD1`	Optional	No	Patient additional demographic	PATIENT_PRIOR
32	`PRT`	Optional	Yes	Participation information	PATIENT_PRIOR
33	`ARV`	Optional	Yes	Access restriction	PATIENT_PRIOR
34	`PV1`	Required	No	Patient visit	PATIENT_VISIT_PRIOR
35	`PV2`	Optional	No	Patient visit - additional info	PATIENT_VISIT_PRIOR
36	`PRT`	Optional	Yes	Participation information	PATIENT_VISIT_PRIOR
37	`AL1`	Optional	Yes	Patient allergy information	ORDER
38	`ORC`	Required	No	Common order	ORDER_PRIOR
39	`PRT`	Optional	Yes	Participation information	ORDER_PRIOR
40	`OBR`	Required	No	Observation request	ORDER_PRIOR
41	`TQ1`	Required	No	Timing / quantity	ORDER_PRIOR
42	`TQ2`	Optional	Yes	Timing / quantity relationship	ORDER_PRIOR
43	`NTE`	Optional	Yes	Notes and comments	ORDER_PRIOR
44	`PRT`	Required	No	Participation information	ORDER_PRIOR
45	`DEV`	Optional	Yes	Device	ORDER_PRIOR
46	`CTD`	Optional	No	Contact data	ORDER_PRIOR
47	`OBX`	Required	No	Observation result	ORDER_PRIOR
48	`PRT`	Optional	Yes	Participation information	ORDER_PRIOR
49	`NTE`	Optional	Yes	Notes and comments	ORDER_PRIOR
50	`FT1`	Optional	Yes	Financial transaction	ORDER
51	`CTI`	Optional	Yes	Clinical trial identification	ORDER
52	`BLG`	Optional	No	Billing	ORDER

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