A 28-year-old man is brought to the emergency department by his husband due to worsening fatigue, dizziness, and a recent syncopal episode. He is a competitive marathon runner who has been rigorously restricting his caloric intake for the past eight months to 'improve race times.' He reports an intense fear of gaining weight and strictly avoids any foods containing fat. Temperature is 35.4°C (95.7°F), blood pressure is 82/50 mm Hg, pulse is 38/min, and respirations are 12/min. BMI is 13.2 kg/m². Physical examination reveals temporal wasting, fine downy hair over his back, and cold, cyanotic extremities. Laboratory studies show:
| Test | Result | Reference Range |
|---|---|---|
| Potassium | 3.1 mEq/L | 3.5-5.0 mEq/L |
| Phosphorus | 2.2 mg/dL | 2.5-4.5 mg/dL |
| Magnesium | 1.4 mg/dL | 1.7-2.2 mg/dL |
An ECG reveals marked sinus bradycardia with a QTc interval of 490 ms. The patient is admitted to the hospital. Arrange the following multidisciplinary management steps in the most appropriate chronological order, from immediate acute intervention to long-term maintenance.
- 1Admit to a medical telemetry unit, restrict physical activity, and slowly correct baseline electrolyte deficits.
- 2Initiate cautious enteral nutritional rehabilitation at a low caloric rate while monitoring serum phosphate, potassium, and magnesium daily.
- 3Transfer to a specialized psychiatric eating disorder unit for a structured behavioral program with supervised meals.
- 4Establish longitudinal outpatient cognitive-behavioral therapy targeting distorted body image and cognitive rigidity.