A nurse is evaluating a preterm infant who has patent ductus arteriosus (PDA).

Which of the following findings should indicate to the nurse that the condition is improving?

Increased oxygen saturation.This indicates that the condition is improving because it means that the blood is getting more oxygen in the lungs and less blood is shunting from the aorta to the pulmonary artery through the patent ductus arteriosus (PDA).

Choice A is wrong because decreased heart rate can be a sign of hypoxia, acidosis, or heart failure, which are complications of PDA.

Choice B is wrong because increased blood pressure can be a sign of increased systemic vascular resistance, which can result from decreased tissue perfusion due to PDA.

Choice C is wrong because decreased respiratory rate can be a sign of respiratory depression, which can be caused by some medications used to treat PDA, such as indomethacin or ibuprofen.

Normal ranges for oxygen saturation in preterm infants are between 88% and 95%.

Normal ranges for heart rate in preterm infants are between 120 and 160 beats per minute.

Normal ranges for blood pressure in preterm infants depend on gestational age and weight.

Normal ranges for respiratory rate in preterm infants are between 40 and 60 breaths per minute.

All of the above factors increase the risk of hyperbilirubinemia in this newborn.Hyperbilirubinemia is a condition of high levels of bilirubin in the blood that can cause jaundice and brain damage.

Choice A is wrong because prematurity is a risk factor for hyperbilirubinemia, especially in babies born before 38 weeks of gestation.Premature babies have immature livers that are less able to process bilirubin and eliminate it from the body.

Choice B is wrong because breastfeeding is a risk factor for hyperbilirubinemia, particularly in some breast-fed babies who do not get enough milk or calories.Breastfeeding can also cause increased enterohepatic circulation of bilirubin, which means that bilirubin is reabsorbed from the intestines into the bloodstream instead of being excreted in the stool.

Choice C is wrong because Asian ethnicity is a risk factor for hyperbilirubinemia, as some Asian populations have higher rates of glucose-6-phosphate dehydrogenase deficiency, a genetic condition that causes red blood cells to break down more easily and release more bilirubin.Asian infants may also have lower levels of uridine diphosphate glucuronosyltransferase, an enzyme that helps convert bilirubin into a form that can be excreted by the liver.

Normal ranges for bilirubin levels vary depending on the age, weight, and health status of the newborn.Generally, bilirubin levels peak between the third and seventh day after birth and then decline gradually.The AAP recommends using a nomogram based on the infant’s age in hours and serum bilirubin level to determine the risk of severe hyperbilirubinemia and the need for treatment.Treatment options include phototherapy and exchange transfusion.