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ADT A05: Pre-Admit a patient


Records an expected future admission of a patient. Additionally, an appointment will be created in the patient's calendar.

Relevant entities

Please click through to the Data Model to explore the presentation of these entities in the web interface.

Update behaviour

Message Entity Matching Criteria Behaviour (Matched) Behaviour (Not Matched)
A05 [[Encounter]] [[Encounter.External Encounter ID]] as derived from PV1-19.1 The [[Encounter Event]] will be handled as indicated below. A new [[Encounter]] will be created with this message.
  [[Encounter Event]] An Encounter can contain zero or one pre-admit [[Encounter Event]]s. If the [[Encounter]] has been matched, then there will be at most one pre-admit [[Encounter Event]], so no other IDs are required for matching. The pre-admit [[Encounter Event]] is replaced with the information in this message. The pre-admit [[Encounter Event]] will be added to the [[Encounter]].
  [[Appointment]] PKB maintains an internal link joining the [[Encounter]] to the [[Appointment]]. No additional external IDs required. The [[Appointment]] information is replaced with the information in this message. A new [[Appointment]] is created and associated with this [[Encounter]].


This is identical in format to the ADT A01, except that an [[Appointment]] entity will also be populated. In addition, since this message is typically used for future events, PV2-8 and EVN-3 will also be considered when determining both the event timestamp and the appointment start time. This is shown below.
Segment Field Component Description Example Data Model
Data Model
[ EVN ]


Timestamp of planned event


EVN-3.1 Timestamp 201508011200 [[Encounter Event.Timestamp]]
if PV2-8 was not provided.
 [[Appointment.Start Timestamp]]
if PV2-8 was not provided.


Patient class


PV1-2.1 Patient class. Allowed values are defined in Code Set PKBCS04. I [[Encounter Event.Class]] [[Appointment.Subject]]



PV1-3.9 Free text description of the location. My Ward [[Encounter Event->Location.Description]] [[Appointment.Location]]

[ PV1-44 ]
Admit datetime. Timestamp of admission for the entire Encounter.


PV1-44.1 Admit timestamp 201508011200 [[Encounter Event.Timestamp]]
if neither PV2-8 nor EVN-3 were provided.

If PV1-44 also not provided, MSH-7 will be used.
[[Appointment.Start Timestamp]]
if neither PV2-8 nor EVN-3 were provided.

If PV1-44 also not provided, MSH-7 will be used.
[ PV2 ]


Expected admit date/time


PV2-8.1 Timestamp 201508011200 [[Encounter Event.Timestamp]] [[Appointment.Start Timestamp]]
[ ZSC ]

The purpose of this custom segment is to allow you to specify attributes of the auto-generated [[Appointment]] which would otherwise be set from the SCH segment for SIU messages.

[ ZSC-8 ]
Appointment type. See here for more information on code sets.


[ ZSC-8.1 ] Appointment type code T01

[ ZSC-8.3 ] Appointment type coding system INT
[[Appointment.Type.Coding System]]

The appointment will not have an end time recorded. [[Appointment.End Timestamp]]


PID|||9999999999^^^NHS^NH||Smith^John^Joe^^Mr||19700101|M|||My flat name^1, The Road^London^London^SW1A 1AA^GBR||^NET~01234567890^PRN~07123456789^PRS|^NET~01234098765^WPN||||||||||||||||N|
PV1|1|I|^^^^^^^^My Ward||||^Jones^Stuart^James^^Dr^|^Smith^William^^^Dr^|^Foster^Terry^^^Mr^||||||||||V00001|||||||||||||||||||||||||201508011000|201508011200


PKB will respond with a standard HL7 acknowledgement.