HL7-Definition V2

The Common Order segment (ORC) is used to transmit fields that are common to all orders (all types of services that are requested). There is some overlap between fields of the ORC and those in the order detail segments. These are described in the succeeding sections. ORC use notes a) placer order groups The Standard supports a mechanism to collect several orders together in a group. Most often this is used to represent an "ordering session" for a single patient. An order group is a list of orders (ORCs) associated with an ORC-4-placer group number. A group is established when the placer supplies a placer group number with the original order. The order group consists of all the ORCs and order detail segments that have the same placer group number. Orders can be removed from the group using cancel, or added using the replacement or parent-child mechanisms. New orders cannot otherwise be added to the group. b) duplicate fields The ORC is intended to uniformly define the fields that are common to all orders (i.e., requested services). Some ORC fields are duplicated in some order detail segments (e.g., OBR, RXO). For example, ORC-2-placer order number has the same meaning and purpose as OBR-2-placer order number field. This promotes upward compatibility with past versions and ASTM. The rule for using these fields is that the value must appear in the order detail segment if it does not appear in the ORC. However, it is recommended to transmit the field value in both places to avoid confusion. c) parent/child – cancel, hold, discontinue During transmission of a request to cancel, hold, or discontinue a parent order, the request is intended to apply recursively to the parent order and all associated child orders. For example: 1) An EKG application receives an order for three EKGs on successive mornings. 2) The EKG application creates three child orders, one for each requested EKG. 3) The first daily EKG has already been performed when a request is received to cancel the original parent order. (The parent is beyond the point of cancellation.) 4) The remaining, unperformed, children are canceled as a result of the request.