A nurse is caring for a post-term newborn who has meconium staining on the nails and umbilical cord.

What is the most likely cause of this finding?

The newborn experienced fetal distress.Meconium staining is often caused by fetal hypoxia or other physiologic stress that triggers the fetus to pass meconium into the amniotic fluid before delivery.If the fetus aspirates the meconium, it can cause lung injury and respiratory distress, termed meconium aspiration syndrome.

Choice A is wrong because a bowel obstruction would not cause meconium staining of the nails and umbilical cord.

Choice B is wrong because a congenital anomaly would not necessarily cause meconium passage or staining.

Choice D is wrong because an infection may cause fetal distress, but it is not the direct cause of meconium staining.Meconium staining may be a sign of infection in the newborn.

A post-term newborn who has macrosomia is at risk of hypoglycemia because the fetus produces more insulin in response to the high glucose levels from the mother.

After birth, the glucose supply from the mother is cut off, but the newborn still has high insulin levels, which can cause low blood glucose.

A heel stick blood glucose test is done to monitor the newborn’s blood glucose level and prevent complications from hypoglycemia.

Choice B is wrong because hyperglycemia is not a common problem for post-term newborns with macrosomia.

Hyperglycemia occurs when there is too much glucose and not enough insulin in the blood.

This is more likely to happen in infants of diabetic mothers who have poor glycemic control during pregnancy.

Choice C is wrong because polycythemia is not related to insulin or glucose levels.

Polycythemia is a condition where there are too many red blood cells in the blood, which can cause increased blood viscosity and clotting.

This can happen in post-term newborns due to chronic hypoxia in utero, which stimulates erythropoietin secretion.

Choice D is wrong because anemia is not related to insulin or glucose levels.

Anemia is a condition where there are not enough red blood cells or hemoglobin in the blood, which can cause decreased oxygen delivery to the tissues.

This can happen in newborns due to blood loss, hemolysis, or decreased production of red blood cells.

The normal range for blood glucose in newborns is 40 to 80 mg/dL (2.2 to 4.4 mmol/L).

A heel stick blood glucose test should be done within the first hour of life and repeated as needed based on the results and clinical signs of hypoglycemia.