Emergency Airway Management in the MRI Suite

Anesthesiology practitioners often need to provide care in a variety of settings, ranging from the emergency department¹ to the post-anesthesia care unit (PACU);² in fact, they may need to follow a patient through many areas of the clinic or hospital. In different spaces and circumstances, the anesthesia provider’s job involves prioritizing issues such as airway management or vital signs monitoring.³ Magnetic resonance imaging (MRI) is a technique to produce images of a patient’s soft tissues, and it is used for imaging the central nervous, musculoskeletal and cardiovascular systems, as well as the pelvis and liver.⁴ MRI technology has evolved extensively over recent years, and it now has an active role inside the operating room.⁴ Also, some patients may need anesthesia within the MRI scanner to reduce anxiety and allow clinicians to obtain the high-quality images.⁵ In either type of case, anesthesia providers must perform their usual duties, such as administering anesthetic drugs, providing mechanical ventilation and stabilizing vitals. In order to give the best care to their patients, anesthesia providers should be familiar with anesthesia in the MRI suite, complications that may arise and emergency airway management for MRI. 

The MRI suite is a highly specialized environment, with intense magnetic fields that create unique problems for patients and clinicians alike.⁵ MRI is based on technology that excites and detects rotational change of protons in the water of living tissues. The powerful magnets of a MRI machine produce a strong magnetic field that forces protons in the body to align with that field. Then, a radiofrequency current is pulsed through the patient, stimulating the protons and straining them against the magnetic field.⁶ As the protons are moved, they emit energy that is detected by a coil in the scanner.⁷ An anesthesia provider should be familiar with the complexities of MRI in order to understand the hazards associated with MRI machines.⁸ MRI technology comes with high levels of noise, systemic and localized heating and accidental projectiles.⁸ Additionally, the MRI environment is dark and may obstruct a clinician’s view of the patient.⁸ Anesthesia providers in particular might be asked to use particular types of airway management devices, such as supraglottic airways (SGAs), to optimize image quality.⁹ Overall, the MRI environment is a busy area for anesthesia providers and patients alike. 

MRI can cause various complications that make an anesthesia provider’s role more difficult. For one, the provider will have reduced access to the patient during the scan, requiring vigilant observation of vital signs and respiration.¹⁰ The patient’s distance from the anesthesiology practitioner creates problems with airway management, intravenous access, patient visualization and monitor application. In some cases, anesthesia providers may need to position themselves within the scanner to evaluate the airway during a scan.¹¹ Additionally, the presence of a magnetic field can create problems with standard anesthesia machines, syringe pumps and vital signs monitors.⁵ Oxygen saturation monitors, for example, are subject to interference from changing magnetic fields and will occasionally be deactivated by radiofrequency currents.¹¹ Machines must be tested and approved in order to be used in the MRI suite, requiring the anesthesia provider to become familiar with such machines and make adjustments if they are not available.⁸ Clearly, anesthesia provision in the MRI suite can be complex and requires high levels of caution. 

In some cases, patients may encounter airway-related issues. In these cases, such as unintentional extubation, clinicians will need to stop the scan and readjust the patient.¹¹ Anesthesia providers should prepare themselves for unanticipated airway emergencies by creating checklists and focusing on teamwork and roles.¹⁰ For example, the anesthesia team can map out zones of the MRI suite and have laryngoscopes, blades and MRI-compatible anesthesia machines available in different areas of the room.¹² Providers should also use acceptable oximeters, and may consider using a laryngeal mask as an adjunct to airway maintenance and support.¹¹ Before administering anesthesia during a MRI, the anesthesiology professional must ensure that all equipment is compatible with the MRI.¹³ Though most airway emergencies can be prevented with proper planning, anesthesia providers should be prepared to stop a MRI scan or move the patient to a different zone at any time. 

Anesthesia provision occurs in many settings, some of which can add complexity to the process. In order to administer anesthesia during MRI, clinicians must understand the basic magnetic functions of the MRI machine, the ways MRI can affect anesthesia machines and practice and the proper management of airway emergencies. Future studies should focus on the best types of ventilation to reduce airway complications while optimizing MRI image quality. 

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