Patient Identification, Gowning & Metal Removal

Patient Identification, Gowning & Metal Removal

The Joint Commission Two-Identifier Mandate & Active Verification

The Joint Commission National Patient Safety Goals (NPSG) establish that healthcare practitioners must use at least two independent patient identifiers prior to administering care, performing diagnostic imaging, or transferring patients. In the MRI department, misidentifying a patient carries dual catastrophic risks: performing an examination on the incorrect anatomical region or wrong individual, and exposing an unscreened patient with contraindicated ferromagnetic implants to the static magnetic field ($B_0$).

Acceptable vs. Prohibited Identifiers

Standard acceptable identifiers include:

• Full legal name (first, middle, and last name as recorded in the legal medical record)
• Date of birth (DOB) (month, day, and year)
• Medical record number (MRN) (unique institutional electronic health record identifier)
• Assigned barcode wristband identification

Active Communication Methodology

Patient identification must always be conducted using active verbal questioning. An Imaging Assistant must never use passive questioning, such as asking, "Are you Mr. Robert Jones?" or "Is your birthday July 14th?"

Patients who are anxious, sedated, hearing-impaired, or cognitively compromised frequently nod or answer "yes" to any authoritative inquiry. Instead, the assistant must directly state:

"Please state your full legal name and date of birth for me."

While the patient speaks, the assistant must simultaneously cross-reference the spoken response against two tangible sources:

1. The patient's identification wristband securely fastened to their wrist or ankle.
2. The electronic health record (EHR) order requisition and MRI safety screening worksheet.

For non-verbal, unconscious, pediatric, or confused patients, identity must be verified by reconciling the patient wristband with an accompanying parent, legal guardian, or designated transport nurse who can explicitly confirm the individual's identity.

Gowning Standards & Invisible Hazards in Zone IV

Under the facility's gowning policy, patients change out of unverified personal clothing into facility-approved and laundered hospital attire, typically 100% cotton or poly-cotton scrubs with fabric ties or non-metallic plastic fasteners.

The Lethal Fallacy of "Safe" Street Clothes

Patients frequently object to gowning, claiming their street clothes contain no metal because they lack external metallic zippers, belts, or buttons. However, street clothes harbor critical hidden hazards:

• Antimicrobial and Anti-Odor Athletic Apparel: High-performance modern sportswear (such as athletic shirts, yoga leggings, compression shorts, and running socks) frequently integrates microscopic filaments of silver ($Ag^+$) or copper. These metallic nanoparticles are woven directly into the synthetic fabric matrix to destroy odor-causing bacteria. Under the intense oscillating radiofrequency (RF) transmit fields of the MRI scanner, these metallic microfibers act as electrical conductors. Induced eddy currents circulate through the fabric, generating rapid resistive heating that produces devastating second- and third-degree skin burns.
• Invisible Fasteners: Hidden brass grommets, concealed magnetic snaps, metallic underwires in brassieres, metallic thread embroidery, and metallic foil branding logos heat rapidly and cause skin contact burns.
• Ferromagnetic Rivets and Zippers: Denim jeans contain heavy steel or brass rivets that distort the local magnetic field and produce severe susceptibility artifacts, in addition to carrying rotational torque risks.

External Metal Screening & Head-to-Toe Removal Protocol

Once the patient is gowned, the Imaging Assistant conducts a meticulous physical inventory to strip all external ferromagnetic and conductive items. Ferromagnetic items become lethal airborne projectiles when accelerated by the static magnetic field gradient, while conductive non-ferromagnetic items create RF burn risks and obscure diagnostic anatomy.

Transdermal Medication Patches & Radiofrequency Heating

Transdermal medication patches deliver continuous systemic drug dosages through the dermis. Some transdermal patch formulations incorporate an aluminized metallic backing or thin metallic foil layer within their laminated structure. This metallic foil acts as an impermeable moisture barrier to maintain steady drug diffusion.

The Burn Mechanism

During an MRI pulse sequence, the scanner's RF body coil transmits high-frequency electromagnetic pulses (typically 64 MHz at 1.5 Tesla, 128 MHz at 3.0 Tesla). When these RF waves encounter the conductive metallic foil of a transdermal patch, they induce circulating electrical eddy currents. Because the metallic layer is microscopic in thickness, its electrical resistance is high, causing immediate and intense resistive heating. The heat is trapped against the patient's skin, resulting in full-thickness contact burns and blister formation.

Product-Specific Patch Review

Patch composition varies by manufacturer and formulation. Identify the medication, brand, strength and application time, then check the current labeling. A drug name alone cannot establish whether its patch contains metal. Some patches require removal before MRI to avoid burns; the treating team must arrange interruption, disposal and replacement without changing the dose inadvertently.

Clinical Management Protocol for Patches

1. Visual Skin Inspection: During the gowning process, the Imaging Assistant must visually inspect the patient's upper arms, back, chest, and flanks for transdermal patches.
2. Technologist and Nurse Notification: The assistant must never independently peel off or discard a prescription medication patch without explicit authorization from the supervising MRI technologist and the patient's registered nurse or physician.
3. Medication disposal: Follow the product labeling and institutional pharmaceutical-waste process. Do not independently flush medication or discard a controlled-drug patch into ordinary trash. Document medication changes through the authorized clinician.
4. Post-Exam Replacement Plan: Ensure that the nursing team is alerted so a fresh patch can be applied immediately following the completion of the imaging exam.

Patient Belongings & Zone II Locker Management

All removed personal belongings must be secured in designated patient lockers located strictly within Zone II, outside the controlled-access doors of Zone III.

Lockers must be secured with physical brass keys, magnetic keycards, or digital electronic keypads. Under no circumstances should locker keys made of ferromagnetic steel be handed to the patient to carry into Zone IV. Belongings management forms must record the locker number, ensuring patient possessions remain protected and preventing unauthorized metal from crossing the Zone III boundary.