Metformin management in the context of radiographic contrast studies—who decides, and what should the Unit Clerk do?

• A. The Unit Clerk decides to hold metformin in all imaging cases.
• B. Metformin may be held due to risk of lactic acidosis with contrast; the clinician decides, and the Clerk flags orders accordingly.
• C. Metformin should never be held; proceed with contrast regardless.
• D. The patient should hold metformin themselves without clinician input.

Answer: (B)

The main idea here is that the decision to withhold metformin around radiographic contrast is a clinical one, made by the treating clinician, while the Unit Clerk’s job is to implement and document that decision.

Metformin may be held around iodinated contrast because of the small but real risk of lactic acidosis if renal function is impacted by the contrast. Because this risk is patient-specific (depends on kidney function, hydration, and other factors), the clinician reviews the individual case and decides whether to stop metformin before the imaging and when to resume afterward. The Unit Clerk then follows through by flagging or withholding the metformin order in the patient’s chart or medication administration record according to that clinician’s instructions, communicating the plan to the patient, and ensuring the resumption orders are in place after the procedure if applicable.

Why the other ideas aren’t right: the decision isn’t automatic for all imaging cases, and it isn’t something the patient should manage on their own. The clinician’s judgment is essential to balance risks and benefits, with the Unit Clerk acting to implement and document the plan.