HL7 ADT_A38 Cancel Pre-Admit

The pre-admission should no longer be treated as active.
HL7 message structure ADT_A38 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
SFT
 Software Segment No Yes
EVN
 Event Type Yes No
PID
 Patient Identification Yes No
PD1
 Patient Additional Demographic No No
PV1
 Patient Visit Yes No
PV2
 Patient Visit - Additional Information No No
DB1
 Disability No Yes
OBX
 Observation/Result No Yes
DG1
 Diagnosis No Yes
DRG
 Diagnosis Related Group No No

ADT_A38 cancels an earlier A05 pre-admit event. Maybe the pre-admit was entered in error, or maybe the plan changed and the patient is no longer expected to be admitted.

Receivers use it to remove or mark inactive the pending pre-admission state. It should not be confused with discharge; there was not necessarily an active inpatient stay to discharge.

A small A38 example

MSH|^~\&|ADT|CITYHOSP|EHR|CITYHOSP|20260715150500||ADT^A38^ADT_A38|ADT380001|P|2.5.1 EVN|A38|20260715150400 PID|1||123456^^^CITYHOSP^MR||Smith^Jane^Anne^^Ms^^L||19800314|F PV1|1|P|PREADM^WAIT^1^CITYHOSP||||12345^Ng^Grace|||||||||||VN000700^^^CITYHOSP^VN

What systems do with it

The sender is usually the PAS/EHR or scheduling/pre-admission module. Receivers clear expected-admission worklists, bed reservations, eligibility checks, pre-registration tasks, and any downstream state created by the original A05.

How to read the structure

The core is MSH, EVN, PID, and PV1. Optional PV2, DB1, OBX, DG1, and DRG may appear when the pre-admit carried extra context that helps receivers find the pending record.

Implementation traps

The receiver should match A38 to the pre-admission it is cancelling. If it cannot find that record, log a useful operational warning rather than silently ignoring the event. Also avoid using A38 to cancel an actual admission; A11 is the cancel-admit workflow for that different case.

Reference notes

The HL7 v2+ ADT_A38 page describes A38 as cancellation of an A05 pre-admit, either due to erroneous entry or a decision not to pre-admit after all.