Emergency medical services
An emergency medical service (abbreviated to initialism "EMS" in many countries) is a service providing out-of-hospital acute care and transport to definitive care, to patients with illnesses and injuries which the patient believes constitutes a medical emergency.  The most common and recognized EMS type is an ambulance organization.
In some places, an EMS organization may also be called a first aid squad, emergency squad, rescue squad, ambulance squad, ambulance service, ambulance corps or life squad.
The aim of EMS is to provide treatment to those in need of urgent medical care, with the goal of either satisfactorily treating the malady, or arranging for timely removal of the patient to the next point of definitive care.  This is most likely an emergency department at a hospital or another place where physicians are available.   In some jurisdictions, EMS units may handle technical rescue operations such as extrication, water rescue, and search and rescue.
In most places in the world, the EMS is summoned by members of the public (or other emergency services, businesses or authority) via an emergency telephone number which puts them in contact with the control center for the EMS, who will then dispatch a suitable resource to deal with the situation.
Throughout the world, there are many differing qualification levels which may be held by members of an EMS, from drivers with no medical training, or a basic first aid certificate, to a fully qualified paramedic or physician.

# History
Emergency care in the field has been rendered in different forms since the beginning of recorded history. The New Testament contains the parable of the Good Samaritan, where a man who was beaten is cared for by a Samaritan. Luke 10:34 (NIV) - "He went to him and bandaged his wounds, pouring on oil and wine. Then he put the man on his own donkey, took him to an inn and took care of him."   Also during the Middle Ages, the Knights of St. John, also known as the Knights of Malta, began to help their injured comrades, forming the basis of the modern Order of Malta Ambulance Corps and St John Ambulance movements.
The first record of ambulances being used for emergency purposes was the use by Queen Isabella of Spain, in 1487.  The Spanish army of the time was treated extremely well and attracted volunteers from across the continent, and part of this was the first military hospitals or 'ambulancias', although injured soldiers were not picked up for treatment until after the cessation of the battle, resulting in many dying on the field.
A major change in usage of ambulances in battle came about with the  ambulances volantes designed by Dominique Jean Larrey (17661842), Napoleon Bonapartes chief physician.  Larrey was present at the battle of Spires, between the French and Prussians, and was distressed by the fact that wounded soldiers were not picked up by the numerous ambulances (which Napoleon required to be stationed two and half miles back from the scene of battle) until after hostilities had ceased, and set about developing a new ambulance system.  Having decided against using the Norman system of horse litters, he settled on two- or four-wheeled horse-drawn wagons, which were used to transport fallen soldiers from the (active) battlefield after they had received early treatment in the field.  These 'flying ambulances' were first used by Napoleon's Army of the Rhine is 1793.  Larrey subsequently developed similar services for Napoleon's other armies, and adapted his ambulances to the conditions, including developing a litter which could be carried by a camel for a campaign in Egypt.
In civilian ambulances, a major advance was made (which in future years would come to shape policy on hospitals and ambulances) with the introduction of a transport carriage for cholera patients in London during 1832.  The statement on the carriage, as printed in The Times, said "The curative process commences the instant the patient is put in to the carriage; time is saved which can be given to the care of the patient; the patient may be driven to the hospital so speedily that the hospitals may be less numerous and located at greater distances from each other".  This tenet of ambulances providing instant care, allowing hospitals to spaced further apart, displays itself in modern emergency medical planning.
The first known hospital-based ambulance service operated out of Commercial Hospital, Cincinnati, Ohio (now the Cincinnati General) by 1865.  This was soon followed by other services, notably the New York service provided out of Bellvue Hospital which started in 1869 with ambulances carrying medical equipment, such as splints, a stomach pump, morphine, and brandy, reflecting contemporary medicine.
Also in the late 19th century, the automobile was being developed, and in addition to horse-drawn models, early 20th century ambulances were powered by steam, gasoline, and electricity, reflecting the competing automotive technologies then in existence.  However, the first motorized ambulance was brought into service in the last year of the 19th century, with the Michael Reese Hospital, Chicago, taking delivery of the first automobile ambulance, donated by 500 prominent local businessmen, in February 1899.  This was followed in 1900 by New York city, who extolled its virtues of greater speed, more safety for the patient, faster stopping and a smoother ride.  These first two automobile ambulances were electrically powered with 2hp motors on the rear axle.
During World War One, further advances were made in providing care before and during transport   traction splints were introduced during World War I, and were found to have a positive effect on the morbidity and mortality of patients with leg fractures.  Two-way radios became available shortly after World War I, enabling for more efficient radio dispatch of ambulances in some areas.  Shortly before World War II, then, a modern ambulance carried advanced medical equipment, was staffed by a physician, and was dispatched by radio.  In many locations, however, ambulances were hearses - the only available vehicle that could carry a recumbent patient - and were thus frequently run by funeral homes. These vehicles, which could serve either purpose, were known as combination cars.
Advances in the 1960s, especially the development of CPR & defibrillation as the standard form of care for out-of-hospital cardiac arrest, along with new pharmaceuticals, led to changes in the tasks of the ambulances.  In Ireland, a mobile coronary care ambulance successfully resuscitated patients using these technologies; and well-developed studies demonstrated the need for overhauling ambulance services. One well-known report in the USA during that time was Accidental Death and Disability: The Neglected Disease of Modern Society. This report is commonly known as The White Paper. These studies, along with the White Paper report, placed pressure on governments to improve emergency care in general, including the care provided by ambulance services.  Part of the result was the creation of standards in ambulance construction concerning the internal height of the patient care area (to allow for an attendant to continue to care for the patient during transport), in the equipment (and thus weight) that an ambulance had to carry, and several other factors.  Few, or perhaps none, of the then-available ambulances could meet these standards.

# The purpose of EMS
An EMS exists to fulfill the basic principles of First Aid, which are to Preserve Life, Prevent Further Injury and Promote Recovery.
This can be built on further, and one commonly used system is outlined here:
- Early Detection (A member of the public finds the incident)
- Early Reporting (The emergency services are summoned)
- Early Response (The emergency services get to scene quickly)
- Good On Scene Care (appropriate treatment is given)
- Care in Transit (the patient is looked after on the way to hospital)
- Transfer to Definitive Care (the patient is handed to the care of a physician)
This system is signified by the Star of Life shown here, where each of the 'arms' to the star represent one of the 6 points

# EMS providers
Depending on your country, area within in country, or clinical need, EMS may be provided by one (or several) organizations, with different reasons for operating the service.  Some countries closely regulate the industry (and may require anyone operating the EMS to be qualified to a set level), whereas others allow quite wide differences between types of operator.
- Government EMS - Operating separately from (although alongside) the fire and police service of the area, these ambulances are funded by local or national government.  In some countries, these only tend to be found in big cities, whereas in countries such as the United Kingdom, almost all emergency ambulances are part of the NHS
- Fire or Police Linked Service - In many countries (USA, France, Germany, Japan), many ambulances are operated by the local fire or police service.  This is particularly common in rural areas, where maintaining a separate service is not necessarily cost effective.  This can lead, in some instances, to an illness or injury being attended by a vehicle other than an ambulance, such as fire truck.  In some locales, firefighters are the first responders to calls for emergency medical aid, with separate ambulance services providing transportation to hospitals when necessary.
- Voluntary EMS -  Some charities or non-profit companies operate ambulances, both the an emergency and patient transport function.  This may be along similar lines to volunteer Fire companies and either community or privately owned.  They may be linked to a voluntary fire service, with volunteers providing both services.  There are also charities who focus on providing ambulances for the community, or for cover at private events (sports etc.).  The Red Cross provides this service in many countries across the world on a volunteer basis (and in others as a Private Ambulance Service), as do some other smaller organizations such as St John Ambulance.  In some countries, these volunteer ambulances may be seen providing support to the full time ambulance crews during times of emergency.
- Private Ambulance Service - Normal commercial companies with paid employees, but often on contract to the local or national government.  Many private companies provide only the patient transport elements of ambulance care (i.e. non urgent), but in some places, they are also contracted to provide emergency care, or to form a 'second tier' response, where they only respond to emergencies when all of the full-time emergency ambulance crews are busy or to respond to non-emergency home calls, such as "pick up and put back" calls, which are made when a person falls without injury, but needs help getting up.  Dependent on their contract they might also provide "first aid only" services, such as providing bandages (but not a trip to the hospital emergency room) to a child who skinned his/her knees at a playground.  They may also be contracted by private clients to provide standby EMS for large events such as sports, conventions, or parades.
- Combined Emergency Service - these are full service emergency service agencies, which may be found in places such as airports or large colleges and universities.  Their key feature is that all personnel are trained not only in ambulance (EMT) care, but as a firefighter and a peace officer (police function).  They may also be found in some smaller towns and cities which do not have the resource or requirement for separate services.  This multifunctionality allows to make the most of limited resource or budget, but having a single team respond to any emergency.
- Hospital Based Service - Some hospitals may provide their own ambulance service as a service to the community, or where ambulance care is unreliable or chargeable.  Their use would be dependent on using the services of the providing hospital.

# Rural/Frontier EMS
The face of rural/frontier EMS has changed dramatically since the 1966 National Academy of Sciences, National Research Council (NAS-NRC) white paper Accidental Death and Disability: the Neglected Disease of Modern Society marked the conception of modern EMS. Ambulance service of that era was more about a fast ride than medical care. It was provided as a low-investment by-product service of funeral homes and others whose primary business already had the requisite type of vehicle.
The NAS-NRC white paper revealed the ill-equipped, ill-trained nature of these services, as well as the potential to do more harm than good. Subsequent reforms led to the birth of modern EMS with the Emergency Medical Services Systems Act of 1973. As standards for training, equipment and care changed, so, too, did the providers of rural/frontier EMS. Dedicated ambulance vehicles staffed by trained EMTs operated by independent volunteer organizations, volunteer fire departments, local hospitals, and others replaced hearses. Many of the previous operators balked at the required investment to meet emerging standards.
In the past three decades, the EMS field, with its capabilities and role as a unique discipline at the crossroads of medicine, public health and public safety, has matured dramatically. At a rural car crash, the gold standard medical response has gone from hearse to helicopter. The pressure to provide advanced life support (ALS), created at first by enthusiastic EMTs within EMS agencies themselves, has become compounded by media-generated public expectation. The drive to provide ALS has had an effect similar to that experienced by funeral home ambulance operators pressed to provide safe, basic care in the early 1970s. More workplace issues arose. The 1950s brought much needed emphasis on the physical and mental health of EMS providers.
EMS agencies dependent on volunteers for staffing and fund-raising for revenue, have found advancement difficult. Indeed, it is often a challenge to continue to assure the timely response of a basic life support ambulance in these settings. In the current era of preparing
public safety for effective response to manage terrorist and other events, the reality of rural/frontier EMS is that the infrastructure upon which to build such a response is itself in jeopardy. The 1996 NHTSA EMS Agenda for the Future,41 the visionary guide upon which this document is based, states that EMS of the future will be community-based health management which is fully integrated with the overall health care system. A theme running through the Rural/Frontier EMS Agenda for the Future is that such EMS integration is not only a reasonable approach to making community health care more seamless and to meeting community health care needs that might not otherwise be met, but that providing a variety of EMS-based community health services may be crucial to the survival and advancement of many rural/frontier EMS agencies.
Another related theme is that EMS should not only weave itself into the local health care system but into the fabric of the community itself. Communities can objectively assess and publicly discuss the level and type of EMS care available, consider other options and accompanying costs, and then select a model to subsidize. Where this happens through a well-orchestrated and timely process of informed self-determination, community EMS can be preserved and advanced levels of care can be attained.
The National Rural Health Association National Rural and Frontier Emergency Medical Services
Agenda for the Future document suggests other means of maintaining an effective EMS presence as well such as alternative methods of delivering advanced life support back-up, and the formation of regional cooperatives for medical oversight, quality improvement, data collection and processing. This document can be accessed here.

# Levels of care
Dependent on the country and area in which the service operates, and what type of provider it is, there may be any one of several levels of EMS crew.  They can broadly be divided in to Basic Life Support (BLS) qualifications (responders, ambulance technicians) which usually involves non-invasive procedures and Advanced Life Support (ALS) qualifications (higher level technicians and paramedics) which includes more invasive procedures (such as intubation and infusion).
Some of the most common qualification terms are:
- First Responder - A person who arrives first at the scene of an incident, and whose job is to provide early critical care such as CPR or using an AED. First responders may be dispatched by the ambulance service, may be passers-by, or may be dispatched to the scene from other agencies, such as the police or fire departments.
- Ambulance Driver - Some services employ staff with no medical qualification (or just a first aid certificate) whose job is to drive the ambulance.  Ambulance drivers may be trained in radio communications, ambulance operations and emergency response driving skills.
- Ambulance Care Assistant - Have varying levels of training across the world, but these staff are usually only required to perform patient transport duties (which can include stretcher or wheelchair cases), rather than acute care. Dependent on provider, they may be trained in first aid or extended stills such as use of an AED, oxygen therapy and other live saving or palliative skills. In some services, they may provide emergency cover when other units are not available, or when accompanied by a fully qualified technician or paramedic.
- Emergency Medical Technician - Also known as Ambulance Technician in the UK and EMT-Basic in the United States.  Technicians are usually able to perform a wide range of emergency care skills, such as defibrillation, spinal care, and oxygen therapy.  Some countries split this term in to several levels (such as in the US, where there is EMT-I and EMT-II and in Alaska EMT-III). This title is not protected in all countries, such as in Great Britain, where anyone can legally call themselves an EMT, even without any training.
- Emergency Medical Technician - Intermediate - This is the next level of Emergency Medical Certification in the National Registry and in Most states. It places the provision of emergency medical care at a level between that of ALS and BLS, allowing for the EMT to perform such duties as IV and IO cannulation, administration of a limited number of drugs, more advanced airway provedures, CPAP, Analgesic Administration, and limited cardiac monitoring and manual defibrilation capabilities. Some states still allow intermediates to practice, but do not issue new intermediate licenses, instead choosing to focus on efforts to go from the Basic to Paramedic route. Some states utilize a modified Intermediate curriculum for training basic EMTs, like the Tennessee EMT-Intervenous Therapy program. In a few other states, the level of Paramedic is actually a Intermediate-level curriculum. This is strictly an American level of licensure.
- Registered Nurse - Some services use specially trained nurses for medical transport work.  These are mostly air-medical personnel or critical care transport providers, often working in conjunction with a technician or paramedic.  They may bring specialized in-hospital skills to the mobile patient care environment, which is especially beneficial to those who may be ill or injured in remote locations that do not enjoy close proximity to definitive hospital intervention and who may require extended care. Registered nurses are more common in countries that have a limited EMS infastructure in place, or in European countries such as France. In the United States, the most common uses of ambulance-based Registered nurses is in the Critical Care/Mobile Intensive Care transport, and in Aeromedical EMS. These nurses in the US are required to seek additional certifications beyond basic RN by their employers, such as Flight Nursing
- Paramedic - This is a high level of prehospital medical training and usually involves key skills not performed by technicians, including cannulation (and with it the ability to use a range of drugs such as morphine), cardiac monitoring, intubation and other skills such as performing a cricothyrotomy. In many countries, this is a protected title, and use of it without the relevant qualification may result in criminal prosecution. In the United States, paramedics represent the highest licensure level of prehospital emergency care in most states. In addition, several certifications exist for Paramedics such as Wilderness ALS Care, Flight Paramedic Certification, and Critical Care EMT-Paramedic (See Below).
- Critical Care Paramedic - Also called an advanced practice Paramedic in some US States, this represents a higher level of licensure above that of the DOT and NREMT-Paramedic curriculum. These Paramedics receive at least six months of additional training beyond normal EMS medicine, including critical care, use of devices and life support systems normally restricted to the ICU or critical care hospital setting, placement and use of UVCs, UACs, surgical airways, facilitated intubation, blood administration, and chest tube insertion. In addition, they receive advanced training in the use of 12-lead EKGs. These represent the highest level of care in the United States, however few states have implemented the program as an official level of licensure. These are New York, Tennessee, and New Jersey. Iowa has a Critical Care Paramedic level,but these paramedics are trained only to the DOT Paramedic Curriculum as entry-level paramedics.
- Emergency Care Practitioner - This is a position sometimes called a 'super paramedic' and is designed to bridge the link between ambulance care and the care of a general practitioner. ECPs are university graduates in Emergency Medical Care or qualified paramedics who have undergone further training, and are authorized to perform specialized techniques. Additionally some may prescribe medicines (from a limited list) for longer term care, such as antibiotics. With respect to a Primary Health Care setting, they are also educated in a range of Diagnostic techniques. This is a level that is not common in the United States, as usually the highest levels of care are the Paramedic or Critical Care Paramedic levels.
- Doctor - Some ambulance services - most notably air ambulances- will employ physicians to attend on the ambulances, bringing a full range of additional skills such as use of prescription medicines. This is less common in the United States, usually restricted to Mobile Intensive Care transports, or pediatric critical care transports that may require surgical or advanced pharmacologic intervention beyond the skills of an EMT, Paramedic or RN.
Depending on the service provider, but most commonly in the Fire and Police linked or combined services, the EMS crew members may also be certified or trained in skills such as water rescue or motor vehicle extrication using the jaws of life in medically directed rescue. Some EMS providers offer different kinds of rescue service including rope rescue, cave rescue, water rescue, extrication, search and rescue and more. Some EMS organizations may have a whole variety of vehicles including boats, response cars and ambulances to deal with the demands of their particular service.
In some places, law requires that all rescue team members be medically certified and in others the main rescue service (such as a Fire Department) do not have medical staff and leave all rescue up to an EMS department.

## Clinical governance
In most areas, the EMS crews will work under the auspices of a medical director, usually a medical doctor, who will set and enforce the standards of clinical care expected of them.  In some areas, such as the United Kingdom, the ambulance crew will be independent clinicians with their own clinical discretion and liability for their own actions.

# Prehospital care strategies
See Organization of the emergency medical assistance: Prehospital care strategies.