Congenital Heart Disease USMLE Step 1 Practice Question
A 2-day-old male infant born to a diabetic mother presents with cyanosis and severe respiratory distress. Vital signs show HR 168/min, RR 52/min, BP 58/35 mmHg, SpO2 75% on room air, and temperature 37.2°C. Chest X-ray demonstrates an egg-on-string appearance. Echocardiography confirms transposition of the great arteries with an intact ventricular septum. Arterial blood gas shows hypoxemia. There is no murmur on cardiac auscultation. Which of the following is the most appropriate immediate management?
Answer choices
- AOxygen therapy and observation
- BProstaglandin E1 infusionCorrect answer
- CUrgent surgical ligation of PDA
- DIndomethacin to promote PDA closure
- EBalloon atrial septostomy alone
- FImmediate intubation and mechanical ventilation with high-concentration oxygen
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