Nonoperating Room Anesthesia (Nora)

Nonoperating room anesthesia (NORA) refers to anesthesia that is provided at locations remote from the familiar territory of the traditional operating room (radiology departments, endoscopy suites, magnetic resonance image [MRI] scanners or dental clinics) (Souter KJ, Pittaway AJ. In: Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Ortega R, Stock MC, eds. Clinical Anesthesia. Philadelphia: Lippincott Williams & Wilkins; 2013:876–890). Nonoperating room (NOR) cases account for a significant proportion of the procedural work of hospitals.

I. The Three-Step Approach to Nora (Fig. 32-1)

The Patient. Patients (especially children) may require sedation or anesthesia to tolerate NOR procedures for a number of reasons (Table 32-1).
The Procedure (Table 32-2)
The Environment. The American Society of Anesthesiologists has developed standards for NOR anesthesia (Table 32-3).

Figure 32-1. A three-step paradigm for NORA.

Table 32-1 Patient Factors Requiring Sedation or Anesthesia for Nonoperating Room Procedures

Claustrophobia, anxiety, and panic disorders
Cerebral palsy, developmental delay, and learning difficulties
Seizure disorders, movement disorders, and muscular contractures
Pain, both related to the procedure and other causes
Acute trauma with unstable cardiovascular, respiratory, or neurologic function
Raised intracranial pressure
Significant comorbidity and patient frailty (ASA grades III or IV)
Child age, especially children <10 yrs

ASA = American Society of Anesthesiologists.

Table 32-2 Common Nonoperating Room Anesthesia Procedures

Radiologic imaging	Computed tomography (CT) Magnetic resonance imaging (MRI) Positron emission tomography (PET)
Diagnostic and therapeutic interventional radiology	Various vascular imaging, stenting, and embolization procedures Radiofrequency ablation (RFA) Transjugular intrahepatic portosystemic shunt (TIPS)
Diagnostic and therapeutic interventional neuroradiology	Occlusive (“closing”) procedures Embolization of cerebral aneurysm, arteriovenous malformation, or vascular tumors Opening procedures Angioplasty, stenting, or thrombolysis in stroke cerebral atherosclerosis or cerebral vasospasm
Radiotherapy	Radiation therapy Intraoperative radiotherapy
Diagnostic and therapeutic interventional cardiology Cardiac catheterization laboratory	Diagnostic cardiac catheterization Percutaneous coronary interventions (PCI) Interventional techniques for management of structural heart disease (transcatheter aortic valve implantation [TAVI]) Placement of left ventricular cardiac assist devices for hemodynamic support
Electrophysiology laboratory (EPL)	Electrophysiology studies and radiofrequency ablation (RFA) Implantation of biventricular pacing systems and cardioverter defibrillators
Psychiatric and therapeutic interventional Gastroenterology	Electroconvulsive therapy Dental restorations Esophageal dilatation or stenting Endoscopic gastrostomy tube placement Endoscopic retrograde cholangiopancreatography (ERCP) Colonoscopy Liver biopsy
Other Procedures	Cardioversion transesophageal echocardiography

Table 32-3 ASA Standards for Nonoperating Room Anesthetizing Locations

Oxygen: Reliable source and full backup E-cylinder
Suction: Adequate and reliable
Scavenging system if inhalational agents are administered
Anesthetic equipment
- Backup self-inflating bag capable of delivering at least 90% oxygen by positive-pressure ventilation
- Adequate anesthetic drugs and supplies
- Anesthesia machine with equivalent function to those in the operating rooms and maintained to the same standards
- Adequate monitoring equipment to allow adherence to the ASA Standards for Basic Monitoring
Electrical outlets
- Sufficient for anesthesia machine and monitors
- Isolated electrical power or ground fault circuit interrupters if “wet location”
Adequate illumination of patient, anesthesia machine, and monitoring equipment
- Battery-operated backup light source
Sufficient space for:
- Personnel and equipment
- Easy and expeditious access to patient, anesthesia machine, and monitoring equipment
Resuscitation equipment immediately available
- Defibrillator, emergency drugs, and cardiopulmonary resuscitation equipment
Adequately trained staff to support the anesthesiologist and a reliable means of two-way communication
All building and safety codes and facility standards should be observed
Postanesthesia care facilities
- Adequately trained staff to provide postanesthesia care
- Appropriate equipment to allow safe transport to main a postanesthesia care unit

ASA = American Society of Anesthesiologists.

II. Patient Safety in Nora

Adverse Events. Respiratory depression secondary to oversedation is the most common type of adverse event in the closed claims study. Capnography provides an earlier monitor of impending respiratory depression during sedation.
Preprocedural checklists (broadly embraced in operating rooms) should be adopted in NOR sites.
Standards of Care for NORA. Guidelines and standards of care for pre- and postanesthesia care, basic monitoring standards, and MAC apply to patients being cared for in all NOR sites in the same way as they do in the operating rooms. The recovery area should be equipped to the same standards as for postoperative patients.
Patient Transfer. Sick, unstable patients may be transferred back and forth between the intensive care unit, the
operating rooms, and NOR locations for imaging or diagnostic procedures. These patients are often mechanically ventilated and receiving a number of drug infusions for both sedation and hemodynamic support. It is also useful to send personnel ahead to secure the elevators to prevent delays during transfer.

III. Sedation and Anesthesia

Definition of Sedation and Anesthesia. Many NOR procedures are performed under “sedation’ or “monitored anesthesia care” (MAC). The Centers for Medicare and Medicaid Services defines Anesthesia as “the administration of a medication to produce a blunting or loss of, pain perception
(analgesia); voluntary and involuntary movements; autonomic function; and memory and/or consciousness.”
The Continuum of Anesthesia. Anesthesia exists along a continuum and the transition from minimal sedation to general anesthesia is not clear cut (Table 32-4).

Table 32-4 Definition of General Anesthesia and Levels of Sedation/Analgesia

	Minimal Sedation (Anxiolysis)	Moderate Sedation/Analgesia (Conscious Sedation)	Deep Sedation/Analgesia	General Anesthesia
Responsiveness	Normal response to verbal stimulation	Purposeful response to verbal or tactile stimulation	Purposeful response after repeated or painful stimulation	Unarousable even with painful stimulus
Airway	Unaffected	No intervention required	Intervention may be required	Intervention often required
Spontaneous ventilation	Unaffected	Adequate	May be inadequate	Frequently inadequate
Cardiovascular function	Unaffected	Usually maintained	Usually maintained	May be impaired