Neonatal Nurse Practitioner Practice Exam

A newborn exhibiting symptoms of atrioventricular canal defect typically presents with which characteristics?

1. Normal heart sounds and no murmurs

2. Ventricular hypertrophy and increased pulmonary markings

3. Increased cyanosis and low respiratory rate

4. Severe hypotonia and weak reflexes

The correct answer is: Ventricular hypertrophy and increased pulmonary markings

A newborn with an atrioventricular canal defect (AV canal defect) typically presents with ventricular hypertrophy and increased pulmonary markings on imaging. This is due to the nature of the defect, which involves a combination of atrial septal defect and ventricular septal defect, leading to increased blood flow to the lungs. The excess blood flow causes the heart, particularly the ventricles, to work harder, resulting in hypertrophy. Increased pulmonary markings are seen on X-rays due to the higher volume of blood returning to the lungs, manifesting as congestion. The combination of these factors highlights the systemic effects of the increased pulmonary blood flow and the resultant cardiovascular changes in newborns with this condition. Normal heart sounds and no murmurs would be atypical in this scenario since parents and clinicians would likely hear significant murmurs caused by the shunting of blood. Increased cyanosis and low respiratory rate might suggest a more severe form of cardiac compromise or another condition altogether. Severe hypotonia and weak reflexes are not typically associated with atrioventricular canal defects but may reflect other underlying neurological or muscular conditions.