Differential cyanosis occurs in: (A) PDA, (B) TGA, (C) Tricuspid stenosis, (D) VSD
Answer is A. Differential cyanosis is present when the preductal (right upper extremity) oxygen saturation is higher than the postductal(lower extremity) saturation.ETIOLOGY:- PDA with reversal of shunt.- Persistent pulmonary hypeension of the newborn.Reverse differential cyanosis:In this condition only the upper pa of the body is cyanosed and the lower pa is pink.ETIOLOGY:PDA +TGV+severe pulmonary hypeensionPDA+TGV+preductal coarctation of the aoa