A CRNA, or Certified Registered Nurse Anesthetist, is an advanced practice nurse who specializes in administering anesthesia. CRNAs are one of the oldest recognized advanced practice nursing specialties in the United States, and they play a central role in surgical care: they provide or contribute to roughly 50 million anesthetics each year across hospitals, surgical centers, dental offices, and military settings.
What CRNAs Actually Do
A CRNA’s job spans the entire arc of a surgical experience. Before a procedure, they evaluate your medical history, identify risks like drug allergies or conditions such as asthma and diabetes that could complicate anesthesia, and explain what to expect. During surgery, they calculate and deliver precise dosages of anesthesia, then continuously monitor your body’s response: heart rate, blood pressure, oxygen levels, and breathing. After the procedure, they oversee your recovery from anesthesia and manage any side effects like nausea or pain.
CRNAs work across a wide range of settings. You’ll find them in hospital operating rooms, outpatient surgical centers, obstetric units, pain management clinics, dental offices, and military facilities. They collaborate with surgeons, anesthesiologists, dentists, and podiatrists. Some pursue fellowships to specialize in areas like chronic pain management.
How CRNAs Are Trained
Becoming a CRNA requires a significant investment in education. Candidates must first earn a bachelor’s degree in nursing, become a registered nurse, and gain hands-on experience in critical care, typically in an intensive care unit. From there, they enter a doctoral-level program. Since 2025, all new nurse anesthesia programs must award a Doctor of Nursing Practice (DNP) or Doctor of Nurse Anesthesia Practice (DNAP) degree, up from the previous master’s degree requirement.
These programs are intensive. Columbia University’s program, for example, runs 36 months full-time and includes a 21-month clinical anesthesia residency. Across all programs, students complete approximately 2,500 hours of hands-on clinical anesthesia care. After graduating, they must pass the National Certification Exam administered by the National Board of Certification and Recertification of Nurse Anesthetists before they can practice.
CRNAs vs. Anesthesiologists
The most common point of confusion is the difference between a CRNA and an anesthesiologist. An anesthesiologist is a physician (MD or DO) who completed medical school followed by a four-year anesthesiology residency. Their clinical training totals 12,000 to 16,000 patient care hours, roughly five to seven times the 2,500 hours a CRNA completes. Both professionals administer the same types of anesthesia, but their educational paths and depth of training differ substantially.
In practice, CRNAs often work in one of three models: independently, under the supervision of an anesthesiologist, or in a collaborative “care team” arrangement where an anesthesiologist oversees multiple CRNAs simultaneously. Which model applies depends largely on state law and facility policy.
Can CRNAs Practice Independently?
This varies by state. Under federal Medicare rules, CRNAs generally must be supervised by a physician when administering anesthesia in a hospital. However, state governors can formally opt out of this federal supervision requirement by submitting a letter to the Centers for Medicare and Medicaid Services, after consulting with the state’s boards of medicine and nursing, attesting that independent CRNA practice is in the best interests of the state’s residents and consistent with state law.
More than 20 states have exercised this opt-out, particularly rural states where anesthesiologists are scarce. In these states, CRNAs can administer anesthesia without physician oversight, which helps maintain surgical access in communities that might otherwise lack it. In states that haven’t opted out, CRNAs typically work under physician supervision or direction.
Patient Safety Outcomes
The question of whether care quality differs between CRNAs and anesthesiologists has been studied extensively, and the evidence is mixed enough that no definitive winner has been declared. A 2014 Cochrane Collaboration review, considered the gold standard for medical evidence synthesis, concluded that available research cannot definitively say one model of anesthesia care is superior to the other.
Some large studies support the safety of independent CRNA practice. A Health Affairs study analyzing over 481,000 Medicare cases found no evidence that unsupervised CRNAs increased patient risk. A separate study of more than 404,000 cases across 22 states found that hospitals without anesthesiologists had results similar to those where anesthesiologists provided or directed care. Research on obstetric outcomes across more than 1.1 million cases similarly found no systematically poorer maternal outcomes in hospitals using CRNAs alone.
Other research points in a different direction. A study of nearly 2.5 million ambulatory surgery cases found that the odds of unexpected complications were 80% higher when a nurse anesthetist provided anesthesia compared to a physician anesthesiologist. An earlier Pennsylvania study of 194,430 cases found 2.5 excess deaths per thousand cases within 30 days when an anesthesiologist was not involved. These studies have been debated on methodological grounds, including whether researchers could accurately determine who actually provided the anesthesia in billing data.
What this means practically: anesthesia in the United States is extremely safe regardless of the provider model, with serious complications being rare. The debate is largely about optimizing care at the margins and has significant professional and economic stakes for both groups.
Salary and Career Outlook
CRNA is one of the highest-paying nursing careers in the country. The median annual salary was $212,650 as of May 2023, according to the Bureau of Labor Statistics. Demand for nurse anesthetists is projected to grow faster than average, driven by an aging population requiring more surgeries, ongoing physician shortages in rural areas, and the cost-effectiveness of CRNA-delivered care. One health economics study concluded that the most cost-effective anesthesia delivery model is CRNAs practicing independently.
Historical Roots
Nurse anesthesia has deep roots in American medicine. The profession traces back to the Civil War, when Catherine S. Lawrence administered chloroform to wounded soldiers during the Battle of Bull Run in 1863, making her the first known nurse anesthetist. In the late 1800s, a shortage of physicians willing to provide anesthesia pushed nurses into the role, with early training programs credited to Catholic nuns and supported by prominent surgeons. Both World Wars further accelerated the training and recruitment of nurse anesthetists, cementing the profession’s place in the healthcare system.