RD2.1 | Patient Suitability Screening for Radiation, Contrast and Magnetic Fields — Summary & Reflection

KEY TAKEAWAYS

Patient Suitability Screening — Key Points

• Imaging safety has two halves: choosing the right modality, and confirming THIS patient can safely undergo it. The requesting clinician owns the suitability screen (competency RD2.1).
• The structured pre-imaging history asks four questions of every patient: allergies (prior contrast reaction), renal function (eGFR), pregnancy status, and implanted devices.
• Radiation screen (X-ray/fluoroscopy/CT/nuclear medicine): justify under ALARA; AERB is India's regulator (Atomic Energy Act 1962). The fetus and children are most radiosensitive — prefer a non-ionising alternative; if an ionising study is necessary, use the lowest dose and shielding.
• Contrast screen: iodinated (CT/fluoroscopy) — high risk at eGFR <30 (CA-AKI); withhold metformin at the time of contrast and for 48 h if eGFR <60 or large volume; premedicate prior severe reactions; note thyrotoxicosis. Gadolinium (MRI) — eGFR <30 risks NSF; prefer macrocyclic agents. Gadolinium contains no iodine and is not a CT alternative.
• Magnetic-field screen (MRI): MRI is NOT contraindication-free — screen for pacemakers/ICDs, cochlear implants, ferromagnetic intra-ocular foreign bodies, and aneurysm clips. Many implants are MRI-conditional (safe only under defined conditions) — identify the exact device; 'conditional' is not 'safe'.
• Integrate the three screens against each request → proceed, modify, or choose an alternative — and document the findings, decision and consent.

REFLECT

Think back to the last imaging request you saw ordered on a ward round. Ask yourself: (1) Did the ordering team establish the patient's allergy/prior-reaction history, renal function, pregnancy status and implant status before the request went down — or were any of these assumed? (2) If contrast or radiation was involved, who weighed the benefit against the specific risk for this patient, and was a safer modality considered? (3) Was the screening decision documented so the radiology team and the next clinician could act on it? Building the habit of running the four-domain screen on every request — automatically, the way you check allergies before prescribing — is what turns suitability screening from a remembered fact into a reliable clinical skill.