Chapter 41
Non-OR Anesthesia

Anesthesia delivered outside the traditional operating room setting has added considerable complexity to our specialty, but it has also expanded our role in the broader healthcare system. As the demand for procedural sedation and anesthesia grows in fields like interventional radiology, endoscopy, cardiology, and diagnostic imaging, so does the need for skilled anesthesiologists who can safely adapt to these variable environments. Currently, 30% of anesthetics are performed outside the operating room, with this number expected to continue to rise over the next decade.

Though it may not seem like a traditional educational setting, NORA provides one of the richest learning environments in your training. I have always felt that if the final training year was spent from 4 to 9 p.m. in a high-volume endoscopy suite, trainees would graduate ready for anything.

NORA requires adaptability, independent judgment, and situational awareness. You are often the only provider with a comprehensive understanding of the patient’s physiology, history, and current risks. You may also be the only clinician in the room with the ability to provide immediate hands-on interventions. At the same time, the environment can offer some distinct advantages, including working in a lower-stakes, more collegial environment. Supportive staff in imaging, IR, or endoscopy suites are often eager to assist if given clear instructions. Your responsibility is to translate the full safety infrastructure of the OR into a less controlled environment, without cutting corners.

Consider three key elements that are as follows:

The goal and urgency of the procedure.
Location and positioning challenges.
Monitoring capabilities and available backup.

A good example is the critically ill patient with decompensated heart failure who requires an endoscopy for GI bleeding while on high-flow oxygen and multiple vasoactive infusions. You may be told the procedure needs “just a little sedation” or that it will be “just a quick look,” but your risk assessment must go deeper. Even brief procedures in very sick patients carry significant complexity, and nothing in this setting is ever truly “just” or “quick.”

Concerns might include:

this patient is likely unable to tolerate even very mild amounts of hypercarbia;
they present with a high aspiration risk given multiple risk factors for residual gastric contents and gut hypoperfusion; and
given the complexity of the case, the procedure is likely to be longer than a usual endoscopy. This is not a patient who can tolerate a long MAC.

In this case, general anesthesia is indicated. And while the risks are real, so is the overall goal: to identify a bleeding source so the patient can undergo cardiac surgery with systemic anticoagulation. The risks should be communicated clearly to the team and to the patient.

When caring for patients in imaging suites or other NORA locations, begin by assessing whether the patient can lie flat without respiratory compromise, whether they are at increased risk for airway obstruction or aspiration, and whether any positioning contraindications exist, such as elevated ICP or spinal instability. Physical distance is a major determinant of safety in these environments; you must be able to reach the airway quickly, deliver medications, adjust vasoactive infusions, and respond immediately to hypoxemia, obstruction, or laryngospasm. Because seconds lost to physical barriers can change outcomes, NORA almost always requires thoughtful preparation, including extension tubing, extra suction lines, and clear access routes.

Infrastructure varies widely across NORA sites, and many lack arterial monitoring, central access capability, advanced infusion pumps, reliable suction, backup oxygen systems, or even dependable communication tools. Machine checks should be especially thorough, as anesthesia machines in these areas are often used less frequently and have a higher likelihood of malfunction. Power failures are uncommon but more likely outside the OR, so always ensure you have a videolaryngoscope, a self-contained ventilator or Ambu bag, and a clear plan if suction or power were to fail. Verify that outlets are generator-backed, test suction early, and have a manual backup ready if it proves unreliable.

NORA may feel like a peripheral part of anesthesia training, but it’s where your ability to think independently, improvise safely, and communicate effectively is truly tested. These are the exact qualities that will serve you throughout your career, whether in a rural hospital, academic center, or solo practice. Learn to love the challenge, and use it to build the habits that will define your clinical maturity.

Specific Scenarios

Imaging

Anesthesia for MRI is commonly required for the pediatric population and adults who cannot lay flat or tolerate the scan due to claustrophobia. If they cannot lay flat because of dyspnea, you might consider this a red flag and look more closely at the etiology.

Sedation without a protected airway (i.e., a propofol MAC) is a popular choice for claustrophobic outpatients, but may be contraindicated in many hospitalized patients who are at risk for having residual gastric contents. Particularly concerning is that you are not close enough to the patient to see or hear early signs of airway failure or emesis—in some cases, you only have access to an ETCO₂ waveform.

Neuro-ICU patients should be screened for high ICP before offering sedation, as ICP issues can be significantly worsened by laying flat, and certainly by hypercarbia that accompanies sedation without a protected airway.

Endoscopy

With over 6 million endoscopies performed in the United States each year, this will make up a sizable proportion of any practice model. Because of the high volume and rapid turnover, this is a good test of your ability to rapidly triage complex patients into their essential components.

Propofol sedation is a popular and efficient choice for most patients. Its popularity belies its ability to cause serious harm if patients are not screened appropriately for airway or aspiration risk. Like any general anesthetic with an unprotected airway, it requires vigilance to maintain spontaneous ventilation. Other adjuvants should be worked in with extreme caution, as even a tiny dose of opiate will potentiate apnea. Unlike a general endotracheal anesthetic, these cases will require continuous titration of a fine line between apnea on one end and patient cooperation on the other. Endoscopy anesthesia will expose you to how different patient populations consume propofol. You will find that a dose as small as 0.2 mg/kg will suffice for an elderly patient, but some teenagers or patients with ramped-up cytochrome P450 activity will still be awake after 2 mg/kg.

Safe propofol sedation relies on (1) an intact airway, (2) no residual gastric contents, and (3) a straightforward, short procedure. For routine cases, you and the endoscopist should accept some amount of patient thrashing/coughing, as this indicates they are still able to breathe and protect their airway. As with any case, if expectations are not aligned, you should address it up front. For any procedure where there is an expectation for zero movement, the safe choice is a general anesthetic with a protected airway. Your first and foremost responsibility is to the patient’s ventilation and oxygenation.

Some amount of hypoventilation during a propofol MAC is expected, but there should always be a clear and consistent waveform of ETCO₂ and chest rise and fall. Absence of a waveform or chest wall movement is always necessary to address. Unstable, uneven, or periodic loss of an ETCO₂ waveform could be an early warning sign for critical hypoventilation, apnea, and resultant cardiac arrest. Upper endoscopy can release “exhalations” of ETCO₂ from the stomach, which can provide false reassurance if you are watching the waveform alone and not the patient. A pulse oximeter is the last sign of impending respiratory arrest. Since the endoscopist shares your value of safe ventilation during the procedure, you should announce when you are troubleshooting ventilation and not keeping it to yourself. They are more willing to help than you think.

Complex airway anatomy, including tumor or trismus, is a relative contraindication to propofol sedation with an unprotected airway.

You should also maintain a lower threshold for general anesthesia in hospitalized patients, who are more likely to have residual gastric contents because of systemic stress, infection, opioids, or recent surgery. The same applies to frail, cachectic patients with chronic illness, whose limited cardiopulmonary reserve and poor nutritional status make even a small aspiration event potentially devastating.