ORC: Common order

Two systems can send the identical order twice and mean opposite things: place this, and cancel this. ORC is the line that says which. Everything else about the order sits in the segment beneath it; ORC says what to do with it.

ORC carries the parts of an order that stay the same whatever is being ordered. Its most important field is the order control code, which says whether the order is being placed, cancelled, held or reported on.

The shape of one line

Where ORC appears

ORC appears in 67 of the 202 message structures the standard defines.

Whole messages

MSH|^~\&|EPIC|STJOSEPH|LABSYS|STJOSEPH|20240314102958||ORM^O01^ORM_O01|ORD20240314-4471|P|2.5.1
PID|1||1000345678^^^STJOSEPH^MR||CARTWRIGHT^ELEANOR^MAY^^^^L||19510822|F
ORC|NW|ORD8842^EPIC|||||^^^20240314103000^^R||20240314102958|USER22^PATEL^NIRAV||1447312^OKONKWO^ADAEZE^^^^MD|3W^^^STJOSEPH|^PRN^PH^^1^503^5550199
OBR|1|ORD8842^EPIC||58410-2^CBC PANEL^LN|||20240314103000

MSH|^~\&|EPIC|STJOSEPH|LABSYS|STJOSEPH|20240314110412||ORM^O01^ORM_O01|ORD20240314-4482|P|2.5.1
PID|1||1000345678^^^STJOSEPH^MR||CARTWRIGHT^ELEANOR^MAY^^^^L||19510822|F
ORC|CA|ORD8842^EPIC|LAB77213^LABSYS||CA||||20240314110412|USER22^PATEL^NIRAV||1447312^OKONKWO^ADAEZE^^^^MD
OBR|1|ORD8842^EPIC|LAB77213^LABSYS|58410-2^CBC PANEL^LN

Every field

Open this ORC message in HL7 Studio

Field notes

• ORC-1Order Control

  Order control, bound to table 0119, and the only field in the segment that changes what the whole message means. NW is a new order, OK acknowledges one, CA cancels, DC discontinues, HD holds, RL releases a held order, RP replaces, RO is a response to an order query, SC is a status change, XO is a change to an existing order. A receiver that ignores ORC-1 and treats every ORM as a new order will duplicate on every cancellation.

  Open ORC-1 in HL7 Studio

• ORC-2Placer Order Number

  Placer order number, the same identifier as OBR-2 and carrying the same value. When both segments are present they must agree, and where they disagree the standard gives ORC precedence. A cancellation is matched to the order it cancels through this field, so it is the field a cancellation cannot omit.

  Open ORC-2 in HL7 Studio

• ORC-3Filler Order Number

  Filler order number, matching OBR-3. Present once the receiving system has accepted the order and assigned its own identifier, and absent on the initial NW.

  Open ORC-3 in HL7 Studio

• ORC-5Order Status

  Order status, bound to table 0038, and distinct from ORC-1. ORC-1 is what the sender is asking for; ORC-5 is where the order currently stands. A is some results available, CA is cancelled, CM is completed, DC is discontinued, ER is an error, HD is on hold, IP is in progress, RP replaced, SC scheduled. The pair NW with a status of SC is an order that has been placed and scheduled, which is different from an order that has been placed and started.

  Open ORC-5 in HL7 Studio

• ORC-7Quantity/Timing

  Quantity and timing, deprecated in v2.5.1 in favour of TQ1. It carries how much, how often and starting when. As with OBR-27, senders are split, so read TQ1 first and fall back to this field.

  Open ORC-7 in HL7 Studio

• ORC-9Date/Time of Transaction

  Date and time of the transaction, meaning when this order event happened. On a cancellation it is when the order was cancelled, which is the timestamp an audit trail needs and is not the same as the original order time in ORC-15.

  Open ORC-9 in HL7 Studio

• ORC-10Entered By

  Entered by, the person who keyed the order, and ORC-12 the ordering provider, the clinician responsible for it. These are regularly different people: a ward clerk enters what a doctor decided. Collapsing them loses the accountability the two fields exist to record.

  Open ORC-10 in HL7 Studio

• ORC-12Ordering Provider

  Ordering provider, and where OBR-16 is absent this is the field results should be routed against. When both are present they normally agree; when they disagree, ORC-12 is the order-level answer and OBR-16 the request-level one.

  Open ORC-12 in HL7 Studio

• ORC-15Order Effective Date/Time

  Order effective date and time, meaning when the order itself takes effect. For a future-dated order this is later than ORC-9, and a system that schedules from ORC-9 will run the order at the moment it was keyed.

  Open ORC-15 in HL7 Studio

Mapping to FHIR

ORC and OBR together become one FHIR ServiceRequest, with ORC contributing the status and the ordering context and OBR contributing what was ordered. ORC-1 does not map to a field: it maps to an action. NW creates the resource, CA and DC set status to revoked, HD sets it to on-hold, and RP means create a replacement with a replaces reference to the original. Treating ORC-1 as data, when it is an instruction, is the most common mistake in this mapping.

Parsing pitfalls

• ORC-1 stored as data when it is an instruction

  The order control code says what to do. A message with ORC-1 of CA is not a new order that happens to be marked cancelled; it is a request to cancel an order the receiver already holds. Storing it as another order leaves the original active.

• ORC-1 and ORC-5 confused

  One is the requested action and the other is the current state. An order can arrive with ORC-1 of SC and ORC-5 of IP, meaning a status change is being reported and the order is in progress. Reading either alone gives half the message.

• ORC and OBR identifiers allowed to drift

  ORC-2 and OBR-2 carry the same placer number and ORC-3 and OBR-3 the same filler number. Where a sender populates only one of each pair, a receiver reading only the other loses the ability to match. Read both and reconcile.

• Order timing taken from ORC-9

  ORC-9 is when the transaction happened and ORC-15 is when the order takes effect. Future-dated and standing orders separate the two, and scheduling from the transaction time executes them immediately.

• Assuming ORC is present

  ORC is optional in ORU result messages and frequently absent. Code that requires it before reading OBR will reject a large share of ordinary result traffic.

Related

• OBRthe request this order control information applies to
• TQ1timing and quantity, replacing ORC-7 from v2.5
• RXEthe pharmacy encoded order that ORC precedes
• OBXresults reported against the order

Message types carrying ORC

ORC appears in 67 message structures, belonging to 53 message types.

• BPS
• BRP
• BRT
• BTS
• CSU
• DFT2
• MDM2
• OMB
• OMD
• OMG
• OMI
• OML3
• OMN
• OMP
• OMS
• ORB
• ORD
• ORF
• ORG
• ORI
• ORL3
• ORM
• ORN
• ORP
• ORR
• ORS
• ORU2
• OSR
• OUL4
• PGL
• PPG
• PPP
• PPR
• PPT
• PPV
• PRR
• PTR
• RAR
• RAS
• RDE
• RDR
• RDS
• RER
• RGR
• RGV
• ROR
• RRA
• RRD
• RRE
• RRG
• RSP5
• VXR
• VXU