An Admission, Discharge, Transfer (ADT) system is a fundamental process in healthcare that tracks a patient’s location and administrative status within a facility or across an entire health system. It monitors a patient’s journey from the moment they enter a hospital until they leave, whether that is through discharge, transfer, or another outcome. This system stores and manages administrative details such as names, contact information, and medical record numbers. By keeping a current record of patient movement, the ADT system ensures that all associated administrative and clinical processes are accurately synchronized.
Defining the Admission, Discharge, Transfer System
The ADT system is primarily a technological concept, centered on automated data messages or feeds generated by a hospital’s Electronic Health Record (EHR) system. These messages are triggered every time a patient’s status changes, providing real-time notification of events. This is an event-driven system, meaning a specific action, like a patient moving rooms, automatically generates a corresponding data message.
These data messages adhere to standardized protocols, most commonly using the Health Level Seven (HL7) framework, which is the globally accepted standard for healthcare data exchange. An ADT message is a structured string of text that communicates administrative and demographic details, ensuring different hospital systems can “speak the same language.”
The system’s main function is to trigger immediate updates across all ancillary systems, including billing, laboratory, radiology, and pharmacy platforms. For instance, when a patient is admitted, the ADT message instantly alerts the billing department to start a new account and the laboratory system to expect new orders. This automated synchronization reduces manual data entry errors and ensures that all departments are operating with the most current patient information.
The Three Core Components of Patient Movement
The acronym ADT represents three distinct patient events that generate specific data messages.
Admission (A)
The Admission (A) event marks the formal start of a patient’s episode of care within the facility. This process includes registering the patient, assigning a unique medical record number, and designating an initial bed or room assignment. The admission message, often coded as an ADT-A01 in HL7, is the first trigger that sets subsequent administrative and clinical workflows into motion.
Discharge (D)
The Discharge (D) event signals the formal conclusion of the inpatient stay. The discharge message (ADT-A03) is sent to finalize the patient’s record and trigger post-visit actions. This event initiates the final billing process, archives the patient’s clinical record, and prompts the preparation of post-discharge instructions.
Transfer (T)
The Transfer (T) event covers any movement of the patient during their stay, which can be either internal or external. An internal transfer (ADT-A02) occurs when a patient moves between departments, such as from the Intensive Care Unit to a general medical floor. An external transfer involves movement to another care setting, such as a different acute care hospital or a long-term skilled nursing facility. The transfer message ensures that the new location and attending physician details are immediately updated across all systems.
Facilitating Seamless Care Coordination
The utility of the ADT system extends significantly beyond the walls of the hospital, directly impacting the quality and continuity of patient care. The real-time ADT messages are increasingly used to notify providers outside the immediate hospital system about a patient’s encounter. These external notifications are sent to the patient’s primary care physician, specialists, and other members of their care team.
This immediate communication helps prevent lapses in care, particularly during the transition from the inpatient setting back to the community. A notification of a patient’s discharge allows the primary care office to proactively schedule a timely follow-up appointment. This rapid intervention helps ensure that the patient understands and adheres to their discharge instructions and medication regimen.
ADT notifications also play a role in medication reconciliation, where the patient’s list of prescribed drugs is compared and updated. By alerting the external provider, the system helps ensure that any new medications started in the hospital do not interact with existing prescriptions. Furthermore, these feeds can update public health registries and health information exchanges, providing a more complete picture of population health.