A nurse is collecting data from an infant.
Which of the following sites is the most reliable location to check the infant’s pulse?

Step 1: The nurse needs to administer 1mg of vitamin K. The available vitamin K injection is 1 mg per 0.5 mL.

Step 2: To find out how many mL the nurse should administer, we divide the required dose by the concentration of the injection. So, 1 mg ÷ (1 mg/0.5 mL).

Step 3: This simplifies to 1 mg × (0.5 mL/1 mg).

Step 4: The mg units cancel out, leaving us with 0.5 mL. So, the nurse should administer 0.5 mL of the vitamin K injection per dose.

Choice A rationale

The statement “My baby will be placed under special lights if the test is elevated” indicates a need for further teaching. This statement is incorrect because phototherapy (special lights) is not used to treat phenylketonuria (PKU). PKU is a genetic disorder that results in the body’s inability to metabolize the amino acid phenylalanine. If left untreated, it can lead to intellectual disability and other serious health problems. The treatment for PKU involves a special diet that is low in phenylalanine. Therefore, the parent’s statement about using special lights for treatment indicates a misunderstanding about the nature of PKU and its treatment.

Choice B rationale

The statement “Sometimes the test is repeated in the doctor’s office at the 2-week check-up” is correct. PKU is usually diagnosed through a routine newborn screening test, and if the initial test results are positive or unclear, the test may be repeated.

Choice C rationale

The statement “My baby must take formula or breast milk before the test is done” is correct. For accurate results, the PKU test is done after the baby is 24 hours old and after the baby has had some protein in the diet.

Choice D rationale

The statement “This test checks for a genetic disorder that can be corrected by diet” is correct. PKU is a genetic disorder that can be managed with a special diet low in phenylalanine.