Emergency medicine

# Overview
Emergency medicine is a branch of medicine that is practiced in a hospital emergency department, in the field by emergency medical service, such as paramedics, and other locations where initial medical treatment of illness takes place.  Just as clinicians operate by immediacy rules under large emergency systems, emergency physicians and other allied health care workers in the emergency department base their practice on a triage system.
Emergency medicine focuses on diagnosis and treatment of acute illnesses and injuries that require immediate medical attention. While not usually providing long-term or continuous care, emergency medicine physicians and paramedics still provide care with the aim of improving long-term patient outcome.
Urgent Care Centers are often staffed by physicians, nurses and nurse practitioners who may or may not be formally trained in emergency medicine. They offer primary care treatment to patients who desire or require immediate care, but who do not reach the acuity that requires care in an emergency department.
Emergency Medicine encompasses a large amount of general medicine but involves virtually all fields of medicine including the surgical sub-specialties. Emergency physicians are tasked with seeing a large number of patients, treating their illnesses and arranging for disposition - either admitting them to the hospital or releasing them after treatment as necessary. The emergency physician requires a broad field of knowledge and advanced procedural skills often including surgical procedures, trauma resuscitation, advanced cardiac life support and advanced airway management.  Emergency physicians ideally have the skills of many specialists - the ability to manage a difficult airway (anesthesia), suture a complex laceration (plastic surgery), reduce (set) a fractured bone or dislocated joint (orthopedic surgery), treat a heart attack (internist), work-up a pregnant patient with vaginal bleeding (Obstetrics and Gynecology), and stop a bad nosebleed (ENT).

# Definition
"Emergency medicine is a medical specialty -- a field of practice based on the knowledge and skills required for the prevention, diagnosis and management of acute and urgent aspects of illness and injury affecting patients of all age groups with a full spectrum of undifferentiated physical and behavioral disorders. It further encompasses an understanding of the development of pre-hospital and in-hospital emergency medical systems and the skills necessary for this development."
International Federation for Emergency Medicine 1991

# History
During the French Revolution, after seeing the speed with which the carriages of the French flying artillery maneuvered across the battlefields, French military surgeon Dominique Jean Larrey applied the idea of Flying Ambulances for rapid transport of wounded soldiers to a central place where medical care was more accessible and effective.  Larrey manned Ambulances with trained crews of drivers, corpsmen and litter-bearers and had them bring the wounded to centralized field hospitals, effectively creating a forerunner of the modern MASH units.  
Dominique Jean Larrey is sometimes called the father of Emergency Medicine for his strategies during the French wars.
Emergency Medicine (EM) as a medical specialty is relatively young. Prior to the 1960's and 70's, hospital "emergency rooms" were generally staffed by physicians on staff at the hospital on a rotating basis, among them general surgeons, internists, psychiatrists, and dermatologists. Physicians in training (interns and residents), foreign medical graduates and sometimes nurses also staffed the ED. EM was born as a specialty in order to fill the time commitment required by physicians on staff to work in the growingly chaotic emergency departments (EDs) of the time. During this period, groups of physicians began to emerge who had left their respective practices in order to devote their work completely to the ED.  The first of such groups was headed by Dr. James DeWitt Mills who, along with four associate physicians at Alexandria Hospital, VA established 24/7 year round  emergency care which became known as the "Alexandria Plan".  Soon, the problem of the "ER", propagated by published reports and media coverage of the poor state of affairs for emergency medical care had culminated with the establishment of the first emergency medicine training program at Cincinnati General Hospital, with Bruce Janiak, M.D. being the first emergency medicine resident in 1970. During the 1970's, several other residency programs developed throughout the country. At this time, EM was not yet a recognized specialty and hence had no primary board certification exam.  It was not until the establishment of ACEP, the recognition of emergency medicine training programs by the AMA and the AOA, and in 1979 a historical vote by the American Board of Medical Specialties that EM became a recognized medical specialty.

# Organizations around the world
In the United States, the American College of Emergency Physicians (ACEP) is presently the largest member organization of emergency physicians (EPs), and Active membership is open to both allopathic (MD,MBBS,MBChB,etc) or osteopathic (DO) physicians. legacy physicians (physicians engaged in the practice of emergency medicine prior to 2000) and those physicians who have completed an emergency medicine residency approved by the Accreditation Council on Graduate Medical Education (ACGME), the American Osteopathic Association (AOA), or are certified by an emergency medicine certifying body recognized by ACEP.  Originally founded in 1968, it was the first Emergency Medicine society formed in the United States. Fellows use the designation FACEP. Membership census: unknown (2006)
The American College of Osteopathic Emergency Physicians (ACOEP) was founded seven years later in 1975. Active membership is open to osteopathic (D.O.) physicians who have practiced emergency medicine for the past three years and/or have completed an emergency medicine residency approved by the AOA or ACGME. Fellows use the designation FACOEP. Membership census: 2,300 (2006)
Founded in 1991, the Association of Emergency Physicians (AEP), distinguishes itself by offering membership to any practicing emergency physician regardless of training. By so doing, the AEP acknowledges that more than half of practicing emergency physicians in the United States, much like their colleagues in other countries, completed residencies in other related specialties which included training in the practice of emergency medicine.  Currently, this organization is the only one allowing non-specialty trained physicians to work within its scope of practice.
The American Academy of Emergency Medicine (AAEM) was formed in 1993 and has been the subject of some controversy due to its traditional position statements concerning board certification, resident "moonlighting", and the practice of "corporate medicine". Nevertheless, AAEM has worked cooperatively alongside the ACEP and the ACOEP when the interests of emergency medicine have called for a united front. Active membership is open to both allopathic (MD,MBBS,MBChB,etc) or osteopathic (DO) physicians who have completed an emergency medicine residency approved by ACGME or the AOA. Fellows use the designation FAAEM. Membership census: 5,000 members (2007)
The American Board of Emergency Medicine (ABEM) provides board certification to allopathic (MD,MBBS,MBChB,etc) or osteopathic (DO) emergency physicians. Although ABEM now requires successful completion of an ACGME-approved residency in emergency medicine followed by completion of an additional year of practice before taking the exam, currently half of the emergency physicians currently holding ABEM certification were "grandfathered" in to certification eligibility via the practice track by training in another specialty, practicing emergency medicine, and then passing the ABEM certification exam.
The American Osteopathic Board of Emergency Medicine (AOBEM) provides board certification to osteopathic (D.O.) emergency physicians who have successfully completed an AOA-approved residency in emergency medicine, completed two years of practice, passed a written exam, and passed an oral exam. Like ABEM, the AOBEM at one time offered certification eligibility via a practice track, allowing training in another specialty, practicing emergency medicine, and then passing the AOBEM certification exam.
The Board of Certification in Emergency Medicine (BCEM) provides board certification to both allopathic and osteopathic physicians that have completed an emergency medicine or primary care residency and performed 5 years of emergency medicine practice, followed by a written and oral examination process. Many of the above mentioned legacy physicians are certified via this pathway.
In the United Kingdom and Ireland, the College of Emergency Medicine sets the examinations that trainees in Emergency Medicine take in order to become consultants (fully-trained emergency physicians). The British Association for Emergency Medicine is the member organization in the UK. In 2005 , the two organizations initiated steps to merge as the College of Emergency Medicine.
In Australia and New Zealand, advanced training in Emergency Medicine is overseen by the Australasian College for Emergency Medicine (ACEM).
In Canada, there are two routes to practice emergency medicine. More than two thirds of physicians currently practicing emergency medicine across the Canadian nation have no specific emergency medicine residency training. Emergency physicians who tend to work in more community-based settings complete a residency specializing in Family Medicine and then proceed to obtain an additional year of training of special competence on Emergency Medicine from the College of Family Physicians of Canada (CCFP-EM). Physicians practicing in major urban/tertiary care hospitals will often pursue a 5 year specialist residency in Emergency Medicine, certified by the Royal College of Physicians and Surgeons of Canada. These members typically spend a great deal of time in academic and leadership roles within emergency medicine, EMS, research, and other avenues. There is no significant difference in remuneration or clinical practice type between physicians certified via either route.
See medical emergency for specific lists of medical emergencies and how best to respond.

# Practice
In the US, Emergency Medicine is a moderately competitive specialty for medical graduates to enter, ranking 7 of 16 specialties in terms of percentage of U.S. graduates whose applications are successful.  However, over 90% of applicants from US medical schools to US Emergency Medicine residencies are successful.       
Allopathic (MD,MBBS,MBChB) emergency medicine residencies can be three or four years in length, depending on the training institution, while all osteopathic (DO) residencies are four years in length, the first being a one-year traditional rotating internship. In addition to the didactic exposure, much of an emergency medicine residency involves rotating through other specialties with a majority of such rotations through the emergency department itself. By the end of their training, emergency physicians are expected to handle a vast field of medical, surgical, and psychiatric emergencies, and are considered specialists in the stabilization and treatment of emergent condition. Emergency physicians are therefore both clinical generalists and well-rounded diagnosticians.
A number of fellowships are available for emergency medicine graduates including toxicology, sports medicine, ultrasound, and pediatric emergency medicine.
The employment arrangement of emergency physician practices are either private (a democratic group of EPs staff an ED under contract), institutional (EPs with an independent contractor relationship with the hospital), corporate (EPs with an independent contractor relationship with a third party staffing company that services multiple emergency departments) or governmental (employed by the US armed forces, the US public health service, the Veteran's Administration or other government agency).
Most emergency physicians staff hospital emergency departments in shifts, a job structure necessitated by the 24/7 nature of the emergency department.

# Advanced Medical Priority Dispatch System
AMPDS stands for the Advanced Medical Priority Dispatch System, and is a piece of computer software used by ambulance services worldwide to prioritize calls by priorty.
The output gives a main response category - A (Immediately Life Threatening), B (Urgent Call), C (Routine Call).  This may well be linked to a performance targeting system such as ORCON where calls must be responded to within a given time period.  For example, in the United Kingdom, calls rated as 'A' on AMPDS are targeted with getting a responder on scene within 8 minutes.
Each call is then assigned a sub-category or code, often used as a means of gathering statistics about performance.  It also helps when analysing the calls for how the call was described by the informant, compared to the injury or illness found when the crew attend.  This can then be used to help improve the questioning system which gives the AMPDS classification.

## Call categorization