Blue Baby Flashcards
Definition of “blue baby”
Congenital heart defects resulting in a right-to-left shunt
Critically small or closed ductus arteriosus
When can central cyanosis be recognised clinically?
When concentration of reduced Hb in the blood reached 5g/dl
Peripheral cyanosis in the first 24hrs of life
Very common
May occur when child is crying/unwell from any cause
“Acrocyanosis”
Aetiology of blue baby
Tetralogy of Fallot
Transposition of great arteries
Tricuspid atresia
What is tetralogy of Fallot?
Pulmonary stenosis in combination with a large ventricular septal defect result in shunting at the ventricular level
What happens in transposition of the great arteries
Aorta and pulmonary trunk have their insertions swapped
What happens in tricuspid atresia?
Right side of heart becomes a dead-end
Clinical features of blue baby
Central cyanosis
Usually limited signs of respiratory distress
Murmur, in the minority
Hepatomegaly
Poor perfusion seen as white peripheries
What does the ductus venosus do?
Connectsumbilical veintoIVC allowing blood tobypass the liver
What does the foramen ovale do?
Connectsright atriumwithleft atriumallowing blood tobypass right ventricle and pulmonary circulation
What does the ductus arteriosus do?
Connectspulmonary arterywithaorta allowing blood tobypass pulmonary circulation
Investigations in blue baby
Nitrogen washout (hyperoxia) test
Differentiates cardiac from non-cardiac causes
Infant given 100% O2 for 10 minutes, ABG taken
pO2 of <15kPa indicates cyanotic congenital heart disease
Management of blue baby
Initial:
Supportive care, prostaglandin E1
Definitive:
Surgical correction of defect or heart transplant
