Emergency medicine is a branch of medicine that is practiced in a hospital emergency department, in the field (in a modified form; see EMS), and other locations where initial medical treatment of trauma and illness takes place.
Emergency medicine is oriented to situations in which care is required immediately and does not usually concern itself with long-term care (although, obviously, EM physicians and pre-hospital technicians will do everything they can in their treatment to improve the long-term outcome of a patient).
See medical emergency for specific lists of medical emergencies and how best to respond.
Links moved from Medicine, to be sorted:
CPR -- Medical Toxicology -- EMS -- History of Emergency Medicine -- Complaint driven medicine -- Traumatology -- Trauma -- Wound care -- First aid -- Paramedic -- Golden Hour