Complete obstruction of the pulmonary artery resulting in total diversion of blood from the right ventricle into the aorta.
1 - atrial septal defect
2 - patent ductus arteriosus
3 - absent pulmonary valve
4 - hypoplastic right ventricle
Abnormal blood flow (as indicated by the shaded blue arrow) is from the right atrium and right ventricle through an atrial septal defect to the left side of the heart. Blood can reach the pulmonary arteries only through a patent ductus arteriosus.
Survival depends on the ductus remaining open in the early days of life (in order for blood to reach the lungs), or on the presence of other connecting blood vessels between the Aorta and the Pulmonary Arteries in the lungs (Collaterals).
Usually born at term, and cyanosis is apparent within hours.
Develop progressively worsening cyanosis and tachypnea associated with closure of the PDA.
Normal arterial pulses usually are present.
IV, O2, Monitor.
3cc/kg/hr D10W for infants under 1 year of age, D5W if over 1 year.
Initial treatment consists of maintaining ductal patency with continuous IV prostaglandin infusion.
To correct metabolic acidosis in a sick neonate, replace fluids and administer sodium bicarbonate.
Foley catheter insertion to follow renal perfusion and urine output.
ABG to follow acidosis.