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Pathology 7

A 4-month-old boy presents to the emergency department with his mother, who has noticed that for the past 2 weeks his lips and extremities are turning blue when he cries or feeds. The infant has also been fussier than usual and does not seem to be putting on weight, which she attributes to him feeding now less than usual. The mother did not have any prenatal care, but the infant was born at term with no complications. Oxygen saturations are at 88% on room air and he is tachypneic with respirations 45/min. On physical examination, the infant is irritable, and is noted to have a cyanotic episode when he is agitated. He is below average weight for his age and height. Tetralogy of Fallot is suspected.

Which of the following abnormalities would not be expected to be found on further investigation?

  • A) Differential cyanosis
  • B) Harsh systolic ejection murmur left sternal edge
  • C) Oxygenation not improving on 100% oxygen for 5 minutes.
  • D) Right axis deviation on ECG
  • E) Right to left shunting of blood in the heart


Octavi Casals Farre


Dr. Ted O'Connell