Can a critically ill patient from the Intensive Care Unit (ICU) undergo a Magnetic Resonance Imaging (MRI) scan?

Can ICU Patients Undergo MRI?

Yes, critically ill ICU patients can undergo MRI, but this requires careful multidisciplinary decision-making, meticulous planning, and should generally be reserved for urgent neuroimaging where rapid treatment will substantially affect patient outcome. 1

Decision-Making Framework

The decision to perform MRI on an ICU patient must be made by the consultant intensivist after discussion with the multidisciplinary team and radiologist, except in exceptional circumstances. 1

When MRI is Justified

• Urgent diagnostic MRI in critically ill patients is generally limited to neuroimaging where rapid treatment will have substantial effect on patient outcome. 1
• In other situations, the risks associated with the investigation may outweigh the benefit, and the scan should be deferred until the patient is less unwell. 1
• Recent research demonstrates that MRI influences clinical course with a change in diagnosis or therapy in 19.2% of all ICU patient scans, and 31.2% in emergency diagnostic cases. 2

Risk-Benefit Assessment

The diagnostic benefit must be weighed against the considerable risks of transporting a critically ill patient to a distant scanner location. 1

• Performing MR scans in critically ill patients is a considerable challenge due to increased risks from the patient's critical condition, the distant location of the scanner, and hazards relating to the MR environment itself. 1
• Approximately one-third of patients transported from ICU to imaging may experience an adverse event, though recent data shows only 0.3% experience potentially life-threatening events during MRI transport and examination. 2, 3
• The rate of premature termination of ICU patients' MRI scans is low (3.7% in emergency cases). 2

Essential Pre-Scan Requirements

Patient Stability Assessment

The physiological stability of the patient determines whether the scan should proceed and the grade of anaesthetist who should accompany the patient. 1

Equipment and Device Review

• A review of monitoring equipment must be made, as devices such as intracranial pressure transducers may be MR Unsafe or MR Conditional. 1
• As the patient may be unconscious or lack capacity, there may be limited information about implants or previous surgery—this must be thoroughly investigated. 1
• Lines for intravenous infusions should be long enough to allow infusion pumps to be located in a safe area while scanning. 1

Staffing Requirements

The anaesthetist must be accompanied by a suitably skilled anaesthetic assistant when an anaesthetic intervention is planned. 1

• The assistant must be adequately trained in safety aspects of the MR environment and be familiar with the location, safety equipment, and how to seek help in an emergency. 1
• In one study, 94.6% of emergency scan patients were ventilated under continuous intravenous medication and monitoring, yet 111 patients were safely accompanied by nurses only during MRI. 2

Procedural Safeguards

Checklist Utilization

Checklists should be used to complete this complex task, as they help ensure meticulous attention to detail required for safe transport and scanning. 1

Planning and Coordination

• The procedure requires careful planning and meticulous attention to detail. 1
• All staff must understand the significance of the MR controlled area and inner MR controlled area. 1
• Staff must be familiar with emergency procedures and understand the need to evacuate the patient from the inner controlled area to deal with emergency resuscitation. 1

Common Pitfalls to Avoid

• Do not proceed with MRI if the patient is physiologically unstable—defer until the patient's condition improves unless the scan will immediately alter life-saving treatment. 1
• Do not allow inexperienced staff unfamiliar with the MR environment to manage patients in this setting, particularly out-of-hours. 1
• Do not overlook the projectile effect—all equipment and personal effects must be screened before entering the MR environment. 1
• Do not assume all monitoring devices are MR-safe—verify the MR safety status of every device before transport. 1

Emerging Alternative: Portable MRI

Recent evidence suggests portable MRI (0.064-T, self-shielding) can be performed safely in ICU rooms, eliminating transport risks entirely. 4

• In 19 ventilated patients with severe COVID-19, portable MRI was performed without any adverse events to patients or staff. 4
• Imaging led to changes in clinical management in 26% of these patients. 4
• This technology may represent the future of ICU neuroimaging, though further studies comparing results with conventional MRI are needed. 4