Oversight of Non–Operating Room Anesthesia

As the number of procedures conducted outside the operating room has increased, so has the number of practitioners providing anesthesia and sedation services to these patients. Many of these patients seen in non–operating room locations are still cared for by anesthesiologists, but providers increasingly come from the departments of medicine, pediatrics, emergency medicine, dentistry, oral surgery, and radiology. Although many factors are driving this change, the involvement of multiple specialties has occurred because many non–operating room procedures do not require a surgical plane of anesthesia. For example, a claustrophobic patient undergoing MRI or an adolescent having a cardiac catheterization who will receive local anesthesia may require only anxiolysis. A toddler having MRI will require deep sedation, whereas an adult undergoing bronchoscopy may require a moderate level of sedation. Nonanesthesiologists have embraced these procedures, as evidenced by the increasing publication of studies of procedural sedation and analgesia in their respective specialty journals. Published investigations by anesthesiologists often include sedation teams with nurse practitioners and pediatricians or radiologists as the personnel providing hands-on sedation. Care by nonanesthesia personnel also may be driven by insurance companies that may not wish to pay for the additional cost of anesthesia services for some of these procedures.

As this transition to multispecialty providers occurs, anesthesiologists remain central to ensuring that all sedation care is as safe as possible. As the pioneers of operating room safety, anesthesiologists are recognized by The Joint Commission as key players in the oversight of non–operating room sedation and anesthesia services, as well as operating room anesthesia. The requirement recently issued by the Centers for Medicare and Medicaid Services (CMS) ^∗

∗ Centers for Medicare and Medicaid Services: http://www.cms.gov/Regulations-and-Guidance/Guidance/Transmittals/downloads/R59SOMA.pdf .

The roles of credentialing, establishing practice guidelines, and providing quality assurance for sedation and analgesia services conducted by other specialties have brought significant challenges to anesthesia departments. Two of these challenges are establishing nil per os (NPO, or nothing by mouth) standards and credentialing practitioners for the use of propofol infusions. Anesthesiologists have long accepted NPO times of 2 hours for clear liquids and 6 hours for other liquids and food to diminish the risk for aspiration. Emergency medicine physicians often encounter patients who would benefit from sedation and analgesia but do not meet these NPO criteria. Several authors from this specialty have questioned the risk for aspiration in nonfasted patients and have attempted to demonstrate the safety of shorter NPO times. The American College of Emergency Physicians published a complex clinical advisory to determine what depth of anesthesia may be given to patients in the emergency room based on fasting from 0 to 3 hours, the urgency and duration of a procedure, and the health of a patient. This advisory uses the terms dissociative sedation, non–extended moderate sedation, and brief deep sedation to describe levels and duration of sedation. These terms are not familiar to most anesthesiologists, nor are NPO times of less than 2 hours for clear liquids or 6 hours for solids acceptable to most anesthesiologists. The American Academy of Pediatrics also has published a guideline on sedation that allows the practitioner to balance the benefit of sedation for emergency procedures against the risk for aspiration for patients who are not on NPO status. Changing attitudes toward NPO times by nonanesthesiologists will be important issues for anesthesiologists who have oversight of these practitioners.

The second controversial issue is credentialing nonanesthesiologists in propofol sedation. Gastroenterologists enthusiastically embraced the use of propofol for patients undergoing endoscopy, starting a debate on the safe use of this drug for deep sedation. The American Society of Anesthesiologists’ (ASA’s) 2004 statement on the safe use of propofol limited use of propofol to “persons trained in the administration of general anesthesia.” In 2009, however, the ASA acknowledged the use of propofol and other anesthetic drugs by other specialists when it published a Statement on Granting Privileges for Deep Sedation to Non-Anesthesiologist Sedation Practitioners. This document describes training, skills, monitoring, and quality assurance review of nonanesthesiologist practitioners to ensure safe delivery of sedation. It requires that a trained individual be solely responsible for sedation and monitoring during propofol administration. Anesthesiologists must continue to provide such guidance to nonanesthesiologists as non–operating room procedures evolve.

Although many articles have been published regarding the safety and efficacy of various sedation regimens and NPO status, caution must be exercised when establishing guidelines for sedation by nonanesthesiologists. Severe complications, including death, are rare, so any comparison of the relative safety of different regimens in hundreds of patients simply lacks the power to establish safety. In addition, moderately severe complications such as respiratory depression are often poorly measured in these studies.

One approach that has been extensively used in anesthesia is the ASA Closed Claims analysis. This method allows examination of adverse events and may help determine risk factors for these events. In 2009, non–operating room closed claims were compared to those in the operating room. Adverse respiratory events, including inadequate oxygenation and ventilation, were the most common cause for NORA claims. Monitored anesthesia care (MAC) was the most common anesthetic, and oversedation and lack of end-tidal carbon dioxide monitoring was the most common scenario encountered. These events happened in older, sicker patients, most often in the gastroenterology suite, and more often resulted in death than events in the operating room. However, closed claims analysis provides only a retrospective look at adverse events, without the benefit of a control group or large number of patients. The Pediatric Sedation Research Consortium was created to improve the understanding of the nature and frequency of adverse events in patients undergoing anesthesia or sedation outside the operating room. The Consortium collects data from 37 different institutions and is thus able to look at sedation encounters in thousands of patients. It recently published articles comparing sedation by pediatricians to that by nonpediatricians, including anesthesiologists, intensive care physicians, emergency room physicians, advanced practice registered nurses, pediatric nurse practitioners, physician assistants, dentists, surgeons, certified registered nurse anesthetists, registered nurses, medical technologists, and radiologists. The Consortium described monitoring modalities used during sedation, compared adverse events among various providers, looked at adverse events during propofol sedation by emergency room physicians, compared propofol to pentobarbital sedation for MRI imaging, compared etomidate versus pentobarbital for CT scans, looked at the incidence and nature of adverse events outside the operating room, and looked at adverse events specifically with propofol sedation outside the operating room. It confirmed that serious adverse events are rare and found no statistically significant difference in the rate of adverse events related to different providers of sedation. However, the Consortium concluded that the safety of pediatric sedation depends on the systems’ ability to manage less serious adverse events.

Levels of Sedation and Anesthesia

The various procedures or diagnostic imaging conducted outside the operating room require different levels of sedation or anesthesia. Diagnostic imaging is usually painless and therefore requires minimal analgesia, whereas interventions may require intraoperative analgesics or postoperative pain management. The continuum of sedation and analgesia can be categorized in different ways. The ASA published a statement defining different levels on the continuum of sedation that apply for any practitioner: minimal sedation (anxiolysis) applies to the patient who is maintaining verbal contact with the practitioner administering sedation. Moderate (previously called conscious) sedation applies to patients who purposefully respond to verbal command or light touch. No airway support should be required, and spontaneous ventilation and hemodynamic stability are maintained. Moderate sedation is often used for short procedures or diagnostic imaging. Deep sedation and analgesia apply to patients who do not respond to light touch but will respond to painful or repeated stimuli. Spontaneous ventilation may not be maintained, and the patient may require intervention to maintain a patent airway. Deep sedation may be appropriate for pediatric patients who must be asleep to be immobile for imaging or for more invasive procedures in adult patients.

In contrast, MAC applies only to a patient who receives care from an anesthesiologist for non-painful or minimally painful procedures in which local or regional anesthesia is provided. MAC allows for administration of sedative and analgesic medicines in doses that exceed those used for moderate sedation and includes the possibility of having the patient go through all of the levels of sedation to general anesthesia, as needed. Even if no medications are used, the presence of the anesthesiologist is required to safely monitor patients who may become unstable.

For many diagnostic and minimally invasive non–operating room procedures, particularly in pediatric patients, the level of sedation required to obtain optimal conditions often is deep sedation. Because the nature of sedation is fluid, it is easy for the patient to go from one level of sedation to the next. All personnel administering sedation to patients outside the operating room must be properly credentialed and trained in rescuing patients from a sedation level deeper than was intended. A practitioner who is planning deep sedation must be able to manage a patient who becomes truly anesthetized. This skill is part of credentialing for anesthesia practice, but many nonanesthesiologist practitioners will need to acquire additional skills and training to gain this ability.