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Eating disorder medical risk — USMLE Step 3 MCQ

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HardPsychiatry (outpatient management)Eating disorder medical riskUSMLE Step 3

A hospitalized adult with anorexia nervosa has had negligible intake for 10 days. Before feeding, phosphorus is 2.1 mg/dL, potassium 3.4 mEq/L, and magnesium 1.5 mg/dL. Which initial order set best follows ASPEN refeeding-risk guidance?

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Correct answer: C — Give thiamine 100 mg before calories; replete deficits and check all electrolytes every 12 hours

The best answer is “Give thiamine 100 mg before calories; replete deficits and check all electrolytes every 12 hours”. ASPEN recommends thiamine 100 mg before feeding or dextrose-containing fluid in an at-risk adult, baseline correction of low phosphorus, potassium, and magnesium, and monitoring about every 12 hours for the first 3 days in high-risk patients. Calories are introduced cautiously and advanced as the clinical state and electrolyte response permit; nutrition is not reflexively withheld for a week.

Reference: ASPEN Consensus Recommendations for Refeeding Syndrome: https://aspenjournals.onlinelibrary.wiley.com/doi/10.1002/ncp.10474