Anesthesia provision in the United States
Anesthesiologists are physicians specializing in the practice of anesthesiology.
The training of a physician anesthesiologist typically consists of 4 years of college, 4 years of medical school, 1 year of internship, and 3 years of residency with an option 1 year fellowship training in anesthesia sub specialties. It is the highest training level for all practitioners delivering anesthesia in the United States, however, while most do, passing a comprehensive board exam is not required. It is not required to be board certified in the USA in order to practice anesthesiology. Physicians who have successfully completed training in an ACGME accredited program become board eligible at the time of graduation and may practice anesthesiology until board certification is attained, commonly within one year post graduation. The majority of physician anesthesiologists practicing in the United States are Board Certified. According to an American Society of Anesthesiologists (ASA) press release Anesthesiologists provide or participate in more than 90 percent of the 40 million anesthetics delivered annually.
Other specialties within medicine are closely affiliated to anesthesiology. These include intensive care medicine and pain medicine. Specialists in these disciplines have completed training in anesthesia including a three year residency in anesthesia with an additional year in an accredited fellowship in a sub specialty of anesthesia (e.g. Pain, Critical Care Medicine, Obstetric Anesthesia, Pediatric Anesthesia). Anesthesiology is not limited to the operating room. Physician anesthesiologists are termed "peri-operative physicians", and are involved in optimizing the patient's health before surgery, performing the anesthetic and associated procedures (e.g neuraxial anesthesia, specialized intravascular access), following up the patient in the post-anesthesia care unit and post-operative wards, and ensuring optimal analgesia throughout. Some sub-specialty physician anesthesiologists are an integral member of the critical care team in Surgical Intensive Care Units (SICU) and manage complex surgical patients throughout their hospitalization.
Anesthesiologist Assistants are non-physician anesthesia providers qualified by advanced education and clinical training to work under the direction of an anesthesiologist in developing and implementing the anesthesia care plan. The anesthesiologist assistant works under the medical direction of an anesthesiologist as an assistant in the Anesthesia Care Team (ACT). Anesthesiologist assistants obtain pre-anesthetic health history, perform preoperative physical exams, establish non-invasive and invasive monitors, administer medications, evaluate and treat life-threatening situations, and execute general and regional anesthetic techniques, as delegated by the anesthesiologist.
Anesthesiologist assistants generally work in the hospital setting but can work at any location where they can be medically directed by anesthesiologists. Anesthesiologist assistants work under the medical direction of physician anesthesiologists in surgical environments such as cardiac surgery, neurosurgery, transplant surgery, and trauma surgery centers. The incorporation of anesthesiologist assistants into ACT teams across the country is a dynamic process, and currently there are sixteen states, as well as Washington D.C. and the Veteran’s Affairs Medical System, in which anesthesiologist assistants are able to work but none currently do. In each of these states, the anesthesiologist assistant falls under the regulatory authority of the State Board of Medicine.
As of 2017 there are twelve anesthesiologist assistant training programs in the United States all of which offer degrees at the Master’s level. Approximately 97% of currently practicing anesthesiologist assistants hold a Master’s degree (some early anesthesiologist assistant graduates held Bachelor’s degrees). All newly credentialed and future anesthesiologist assistants must complete an accredited Master’s program for anesthesiologist assistants. Upon completion of the educational program, graduates must sit for a credentialing exam that is co-validated by the National Board of Medical Examiners and National Commission for Certification of Anesthesiologist Assistants. All anesthesiologist assistant programs are credentialed by the Commission on Accreditation of Allied Health Educational Programs (CAAHEP)
Nurse anesthetists are advanced practice registered nurses specializing in the provision of anesthesia are Certified Registered Nurse Anesthetists (CRNAs). As of 2018, CRNAs represent 50% of the anesthesia workforce in the United States, with 52,000 providers, according to the American Association of Nurse Anesthetists, and administer approximately 40 million anesthetics each year. Thirty-four percent of nurse anesthetists practice in communities of less than 50,000.
CRNAs begin their education with a four-year Bachelor of Science degree approximately 1 year of critical care nursing experience and complete the CCRN certification. During 3 years of graduate school focusing on anesthesiology, they practice to complete a doctoral degree in nurse anesthesia and must pass the NBCRNA national certification exam.
CRNAs care for patients pre-, intra-, and postoperatively and practice in all facets of anesthesia care. They may care for patients independently or collaboratively. Some choose to narrow the focus of care to sub specialize in the provision of cardiac, pediatric, pain, or obstetrical care. They perform all types of anesthesia care including general endotracheal and neuroaxial, as well as perform advanced intravascular access as needed.
As of 2014, 17 governors opted out of the CRNA supervision requirement of the Centers of Medicare and Medicaid Services (CMS). The remaining states maintain that CRNAs must work with podiatrists, dentists, anesthesiologists, surgeons, obstetricians or other professionals with similar anesthesia training.
CRNAs administer anesthesia in all types of surgical cases, and are able to apply all of the accepted anesthetic techniques—general, regional, local, or sedation. Nurse Anesthetists are able to practice anesthesia independently in some states and often form independent, cost effective, anesthesia service groups with safety equal or surpassing public standards of care. CRNAs also work as well in Anesthesia Care Teams.
Effective November 13, 2001, CMS established an exemption for Certified Registered Nurse Anesthetists (CRNAs) from the physician supervision requirement. This exemption recognized a Governor's written request to CMS attesting that he or she is aware of the State's right to an exemption of the requirement for CRNA to be supervised by a physician trained in the provision of anesthesia. The attestation recognizes it is in the best interests of the State's citizens to exercise this option in order to provide safe, cost effective, valuable anesthesia services and especially helps assure provision of those services to all citizens. As of September 2014, seventeen States have chosen to opt-out of the CRNA physician supervision regulation. The States are: California, Iowa, Nebraska, Idaho, Minnesota, New Hampshire, New Mexico, Kansas, North Dakota, Washington, Alaska, Oregon, South Dakota, Wisconsin, Montana, Colorado, and Kentucky. 
Anesthesia Care Teams
According to the ASA statement on the Anesthesia Care Team, anesthesia care personally performed or medically directed by an anesthesiologist constitutes the practice of medicine. According to the American Association of Nurse Anesthetists and state law in all fifty states, anesthesia care provided by a Certified Registered Nurse Anesthesiologist is considered the practice of nursing. Certain aspects of physician directed anesthesia care may be delegated to other trained and credentialed professionals, including Anesthesia Assistants who require Anesthesiologists supervision.
Law regarding anesthesia provision
It has been established that, under US law, anesthesia is both the practice of medicine and nursing. Frank v. South, Chalmers-Francis v. Nelson and other court decisions determined that anesthesia was the practice of Nursing as well as Medicine. As such, the practice of anesthesia in the US may be delivered by either a nurse anesthetist or physician anesthesiologist. The decisions have not been challenged since the Dagmar Nelson case. In addition to legal decisions, individual hospital and surgical facility policies also regulate the granting of anesthesia clinical privileges and are often based on contractual agreements with provider groups.
- "ASA Fast Facts: Anesthesiologists Provide Or Participate In 90 Percent Of All Annual Anesthetics". ASA. Archived from the original on 2007-02-02. Retrieved 2007-03-22.
- NBCRNA NCE http://www.nbcrna.com/certification/Pages/default.aspx. Retrieved 9 July 2016.
- "Legal Issues of Nurse Anesthesia Practice" (PDF). American Association of Nurse Anesthetists. May 2010. Retrieved 17 January 2016.
- "Anethesiology Care Team". durhamregional.org. Archived from the original on 2006-08-21. Retrieved 2007-02-11.
- "Spotlight" https://www.cms.gov/Regulations-and-Guidance/Legislation/CFCsAndCoPs/Spotlight.html CMS.gov Retrieved 9 July 2016.
- "The ASA Anesthesia Care Team statement" (PDF). American Society of Anesthesologists. October 13, 2013. Retrieved January 17, 2016.
- 175 Ky 416, 194 SW 375 (1917)
- 6 Cal 2d 402 (1936)
- "The Practice of Anesthesia (Position Statement)". American Association of Nurse Anesthetists. Retrieved 17 January 2016.
- "The administration of anesthesia and the practice of medicine". AANA. 2006-02-01. Archived from the original on 2007-10-21. Retrieved 2007-02-10.