A nurse is planning to obtain a blood specimen from a newborn via a heel stick.
Which of the following actions should the nurse take?

Choice A rationale

A positive finding for galactosemia, not PKU, indicates the inability to metabolize galactose. Galactosemia is a different metabolic disorder that requires a separate dietary intervention.

Choice B rationale

A positive PKU test does not indicate slow metabolism. Instead, it signifies the inability to metabolize phenylalanine, an amino acid.

Choice C rationale

Phenylketonuria (PKU) is a genetic disorder that leads to the inability to break down the amino acid phenylalanine. Without proper management, it can accumulate in the body and cause brain damage and other health issues.

Choice D rationale

A positive PKU test is not directly linked to an increased risk for neurological anomalies in general. The specific issue in PKU is the inability to metabolize certain amino acids, primarily phenylalanine, which can cause neurological damage if untreated. .

The correct answer is Choice A

Choice A rationale: Blood urea nitrogen (BUN) level of 25 mg/dL exceeds the normal range of 10 to 20 mg/dL and may indicate impaired renal function or dehydration. In pregnancy, elevated BUN is concerning because renal perfusion is typically increased, leading to lower BUN levels. A rise suggests possible renal compromise, which can affect fetal development and maternal health. It warrants provider notification to assess for underlying pathology such as preeclampsia or renal insufficiency.

Choice B rationale: Hemoglobin level of 10.2 mg/dL is slightly below the normal pregnancy range of 11 to 16 mg/dL, indicating mild anemia. However, in the context of pregnancy, especially with a known history of anemia, this value is not critically low. Iron supplementation and dietary adjustments are typically sufficient. It does not represent an acute complication unless accompanied by symptoms like fatigue, pallor, or tachycardia. Therefore, it does not require immediate provider notification.

Choice C rationale: Fasting blood glucose of 70 mg/dL is at the lower end of the normal range for pregnancy, which spans from 70 to 110 mg/dL. This value is physiologically acceptable and does not indicate hypoglycemia or gestational diabetes. During pregnancy, insulin sensitivity fluctuates, but a fasting glucose of 70 mg/dL is not pathologic. No intervention is needed unless symptomatic hypoglycemia occurs. Thus, this result is not indicative of a prenatal complication.

Choice D rationale: Hematocrit level of 32% is slightly below the normal pregnancy range of 33 to 47%, reflecting mild dilutional anemia due to plasma volume expansion. This is a common physiological adaptation in pregnancy and not necessarily pathologic. Unless accompanied by symptoms or a significant drop in hemoglobin, this value alone does not indicate a prenatal complication. Monitoring and nutritional support are appropriate, but urgent provider notification is not required.