HEALTHCARE SYSTEMS CONNECTORS

ADT & Patient Management

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Synchronize patient demographics, admissions, transfers, discharges and encounter context between HIS/EHR systems and Mediloop using HL7 v2 ADT and FHIR.

HL7 v2 ADTPatientEncounterLocationPractitionerOrganizationMPIACK / NAK

End-to-End ADT Flow

HIS / Source System

Sends real-time HL7 v2 ADT patient events

Mediloop Connector

Receives, validates and acknowledges ADT messages

Identity Resolution (MPI)

Matches identifiers and detects duplicates

MSIS – Semantic Layer

Normalizes and validates patient/encounter data

Patient / Encounter

Creates or updates FHIR-aligned records

Downstream Services

Clinical apps, APIs, events and analytics

HL7 v2 ADT Events

Event	Code	Description	Direction
Admit / Visit Notification	A01	Patient admission / visit	Inbound
Transfer	A02	Patient transfer to another location	Inbound
Discharge	A03	Patient discharge / end of visit	Inbound
Registration	A04	Patient registration	Inbound
Pre-admission	A05	Pre-admission information	Inbound
Update Patient Info	A08	Demographic information update	Inbound
Cancel Admit	A11	Cancel admission	Inbound
Cancel Transfer	A12	Cancel transfer	Inbound
Cancel Discharge	A13	Cancel discharge	Inbound
Merge Patient	A40	Merge patient accounts	Inbound

Return ACK (accept) or NAK (reject) with correlation identifiers and validation details.

FHIR Resource Mapping

FHIR resource	Purpose	Key fields
Patient	Patient demographics and identifiers	identifier, name, gender, birthDate, telecom, address
Encounter	Encounter / visit management	status, class, type, period, serviceProvider, location
Location	Hospital and care locations	name, type, address, managingOrganization
Practitioner	Attending / responsible professionals	identifier, name, telecom, qualification
Organization	Hospitals / departments	identifier, name, type
RelatedPerson	Contacts / next of kin	name, relationship, telecom

Identity Resolution & MPI

Deterministic matching

National / enterprise patient identifiers

MRN + assigning authority

Exact demographic combinations

Known cross-system identifier links

Probabilistic / review path

Name, birth date, address and contact similarity

Duplicate candidate scoring

Ambiguous matches routed to controlled review

Never auto-merge uncertain identities

Developer Integration Surface

How to read this section

FHIR resources and HL7/IHE operations are standards-based integration surfaces. Mediloop REST routes shown here are documentation contracts and must remain marked planned until the corresponding backend route is implemented and production-approved.

Surface	Operation / resource	Use	Status
HL7 v2	ADT A01/A02/A03/A04/A05/A08/A11/A12/A13/A40 + ACK/NAK	Real-time patient and encounter events	Protocol operation
FHIR	Patient / Encounter / Location / Practitioner / Organization / RelatedPerson	Standards-based patient/encounter read/write/search	FHIR surface
Events	patient.updated, encounter.started, encounter.transferred, encounter.discharged	Subscribe downstream workflows to lifecycle changes	Planned contract
REST / SDK	ADT ingestion status, identity review, reconciliation	Operational façade for modern apps and migration projects	Planned contract

Reliability & Reconciliation

Idempotent processing using message control ID + source system

Ordering safeguards for out-of-order ADT events

Retry + DLQ for transient failures

Reconciliation reports for unmatched/failed messages

Merge/unmerge audit trail for patient identity changes

Preserve original HL7 payload and mapping provenance

Security & Best Practices

Use TLS/mTLS or protected network channels

Validate sending facility/application and tenant context

Apply least-privilege connector credentials

Do not silently overwrite conflicting demographics

Monitor ADT lag, rejected messages and duplicate rates

Test cancel/merge edge cases before production