Acute assessment unit
An acute assessment unit (AAU) (also often called acute admissions unit or acute medical assessment unit) is a short-stay department in some British, Australian and New Zealand hospitals that may be linked to the emergency department, but functions as a separate department. The AAU acts as a gateway between a patient's general practitioner, the emergency department, and the wards of the hospital. The AAU helps the emergency department produce a healthy turnaround for patients, helping with the four-hour waiting rule in the United Kingdom. An AAU is usually made up of several bays and has a small number of side-rooms and treatment rooms. They are fully equipped with emergency medical treatment facilities including defibrillators and resuscitation equipment.
From the emergency department, patients can be moved to AAU where they will undergo further tests and stabilisation before they are transferred to the relevant ward or sent home. Also, patients can be admitted straight to AAU from their general practitioner if he or she believes the patient needs hospital treatment. A patient's stay in the unit is limited, usually no more than 48 hours.
The AAU deals with admissions only, patients will never be transferred from a ward to the AAU. Surgical procedures are not carried out in the unit either; these are referred on to the relevant theatre such as cardiothoracics and general surgery.
Senior staff in an AAU typically include a consultant in general medicine, emergency medicine, or critical care. Often a registrar in general medicine, and a ward sister or a charge nurse have roles in the unit. A number of staff nurses work alongside the senior staff to provide care to patients in the unit. The department can also include pharmacists, who carry out duties such as medical history taking.
Although AAU has its own staff trained to deal with patients and provide care, members of staff from other departments in the hospital are needed in AAU to assess patients and provide further diagnosis. Typical examples of staff who may be needed in AAU are general surgeons, cardiothoracic surgeons, cardiologists, and a psychiatric liaison nurse.
Alternative names for the department
Different hospitals use different names for the department. Common names for this department are:
- Acute Assessment Unit (AAU)
- Acute Admissions Unit (AAU)
- Acute Medical Unit (AMU)
- Acute Medical Receiving Unit (AMRU) 
- Children's Acute Assessment Unit (CAA) 
- Clinical Decision Unit (CDU)
- Emergency Assessment Unit (EAU)
- Emergency Care Unit (ECU)
- Emergency Medical Assessment/Admissions Unit (EMAU)
- Medical Assessment Unit (MAU)
- Medical Assessment and Planning Unit (MAPU) - in Australia and New Zealand
- Chelsea and Westminster Hospital: Acute Assessment Unit (AAU) Linked 2013-07-20
- West Hertsfordshire Hospitals: Acute Admissions Unit Linked 2013-07-20
- Ealing Hospital: Acute Medical Unit (AMU) Linked 2013-07-20
- University Hospital of South Manchester: Ward A10 (AMRU) Linked 2013-07-20
- Christchurch Hospital: Children’s Acute Assessment Unit (CAA)
- Blackpool Teaching Hospitals: Clinical Decisions Unit Linked 2013-07-20
- Salford Royal: Emergency Assessment Unit (EAU) Linked 2013-07-20
- Royal Hampshire County Hospital: Emergency Medical Assessment Unit (EMAU) Archived April 13, 2013, at the Wayback Machine. Linked 2013-07-20
- Frimley Park Hospital: Medical assessment unit (MAU) Linked 2013-07-20
- IMSANZ: Standards for MAPU in Public and Private Hospitals Linked 2013-07-20