Congenital Heart Diseases
The pediatric patient who presents with cyanosis should raise concern for one of several possible congenital heart conditions. These include: truncus arteriosus, transposition of the great vessels, tricuspid atresia, tetralogy of fallot and total anomalous pulmonary venous return.
Approximately 1% or 40,000 births per year in the United States yearly.
In each of these congenital defects, there is some degree of deoxygenated blood bypassing the lungs and entering the systemic circulation.
Truncus arteriosus: in this condition, the truncus arteriosus (an embryological structure) fails to divide into the pulmonary trunk and aorta. As a result, mixed oxygenated blood is sent to the systemic circulation.
Transposition of the great vessels: deoxygenated blood from the right side of the body is pumped into the systemic circulation and oxygenated blood from the left side of the body is pumped into the lungs.
Tricuspid atresia: complete absence of tricuspid valve leads to impairment of the heart to effectively oxygenate the body.
Tetralogy of fallot: defects including overriding aorta, pulmonary valve stenosis, right ventricular hypertrophy and ventricular septal defect cause shunting of deoxygenated blood to mix with systemic blood.
- Total anomalous pulmonary venous return: the pulmonary veins are malpositioned and return blood to the right side of the heart, rather than the left side, therefore, preventing adequate oxygenation of the body.
Signs and Symptoms
Most concerningly, the child will present with features of central cyanosis, which includes cyanotic mucous membranes of the mouth. When the child is placed on 100% nonrebreather, the child will fail to increase their PaO2 if it is a cyanotic congenital heart defect. Pallor, mottling, new heart murmur, irritability and lethargy are other clues to look for.
The following tools will be useful:
CXR: may demonstrate increased pulmonary markings, boot shaped heart in tetralogy of fallot.
EKG: often demonstrates right axis deviation and right ventricular hypertrophy in cyanotic heart lesions.
- Echo: gold standard for establishing a diagnosis of cyanotic congenital heart defect.
Treatment and Management
For many neonates with cyanotic congenital heart defects, they are dependent on a patent shunt physiology. In the management of these patients, it is therefore critical to maintain a patent shunt through the administration of prostaglandins.
Administer prostaglandin E1, 0.05 to 0.1 microgram/kg/min. Be aware that a major side effect includes apnea.
For tet spells, position the patient in a knee to chest and administer morphine 0.2mg/kg.
- Immediate consultation with a pediatric cardiologist and admission.
Tintinalli’s 7th edition: Chapter 72 - Pediatric Heart Disease
- Wikipedia: en.m.wikipedia.org/wiki/Anomalous_pulmonary_venous_connection