As modern healthcare evolves, more procedures are being performed outside of traditional operating rooms. This shift has led to the development of a specialized field known as Non-Operating Room Anesthesia (NORA), a practice dedicated to providing anesthetic care in locations like radiology suites, endoscopy units, cardiac catheterization labs, and interventional radiology settings. Tracing the history of anesthesia shows steady and ongoing expansion of NORA through the present day.
In prior eras of medicine, anesthesia was almost exclusively delivered in operating rooms or theatres. However, the growing success of minimally invasive and image-guided procedures in the 1980s and 1990s began to change that. Physicians began performing more diagnostic and therapeutic interventions outside the OR, allowing for improved hospital efficiency. Consequently, a need for safe and effective sedation and anesthetic support in these new, non-specialized settings developed.
This need produced the NORA sub-specialty, though it was not widely recognized as a distinct sub-specialty until the early 2000s. As demand increased, so did efforts to improve safety and standardization. The American Society of Anesthesiologists (ASA) issued updated practice guidelines specifically for sedation and anesthesia care in non-OR settings (ASA 2013). These guidelines emphasized the importance of monitoring standards, provider expertise, airway readiness, and facility preparedness.
Growing “official” support and evidence of safety sparked a major milestone in the history of anesthesia—a boom in interest in and utilization of NORA. Many hospitals and ambulatory centers began investing in mobile anesthesia machines, transport monitors, and dedicated anesthesia staff trained in NORA environments. At the same time, advances in short-acting sedatives, non-invasive monitors, and safety protocols have made NORA procedures more feasible and patient-friendly.
Today, some institutions report that more than 30% of cases requiring anesthesia now occur outside of the OR (Routman et al, 2024). Much of this growth has been driven by an aging population, increased comorbidities, and an increase in outpatient procedures that do not require deep sedation or advanced monitoring (Woodward et al, 2017). However, it has remained a challenge comparing outcomes between OR and NORA interventions because of confounding operational, structural, and patient comorbidity contexts (Wong et al, 2017). For example, the efficiency standard of NORA cannot be compared to that of an OR procedure due to independent staffing and resource expectations. Additionally, patient demographics differ across these two settings (Metzner et al, 2010).
Regardless, NORA remains as a valuable adjunct to traditional OR anesthesia. As technology continues to advance and patient preferences shift toward less invasive, outpatient treatments, the importance of NORA will continue to grow. Future improvements in remote monitoring, tele-sedation protocols, and AI-supported risk assessment could further expand the reach of safe anesthesia beyond the OR.
References
American Society of Anesthesiologists. Statement on Nonoperating Room Anesthetizing Locations. July 2022. Accessed October 2025. Available from: https://www.asahq.org/standards-and-guidelines/statement-on-nonoperating-room-anesthetizing-locations
Metzner J, Domino KB. Risks of anesthesia or sedation outside the operating room: the role of the anesthesia care provider. Curr Opin Anaesthesiol. 2010;23:523–531.
Routman JS, Tran BK, Vining BR, et al. Non-operating room anesthesia workflow (NORA) implementation to improve start times in interventional radiology. Curr Probl Diagn Radiol. 2024;53(4):477-480. doi:10.1067/j.cpradiol.2024.03.009
Woodward ZG, Urman RD, Domino KB. Safety of non-operating room anesthesia: a closed claims update. Anesthesiol Clin. 2017;35(4):569-581. doi:10.1016/j.anclin.2017.07.003
Wong T, Tsai MH, Urman RD. The expansion of non-operating room anesthesia services. Perioper Care Oper Room Manag. 2017;9:39–42. doi:10.1016/j.pcorm.2017.11.008