A nurse in the emergency department is caring for a school-age child who has developed respiratory stridor, wheezing, and urticaria after receiving an IV medication. Which of the following actions should the nurse take first?

A. Negative doll's eye reflex (also known as oculocephalic reflex) is a normal finding in infants. It is a reflexive movement of the eyes in the opposite direction of the head
movement.

B. A sunken anterior fontanel can indicate dehydration, which is a concern. However, in a 2-month-old with heart failure, a high heart rate (tachycardia) may indicate worsening of the heart failure and needs to be addressed promptly.

C. A potassium level of 5.1 mEq/L is within the normal range for infants. While electrolyte balance is important, it is not the priority in this situation.

D. This is the correct answer. A heart rate of 162/min in a 2-month-old infant with heart failure is elevated and requires immediate attention. It may indicate worsening heart
failure or an adverse reaction to the medication (furosemide) being administered. The nurse should assess the infant's condition, notify the healthcare provider, and intervene as necessary.

A. Starting the IV in the infant's foot is not the preferred site for a 12-month-old who is ambulatory or beginning to walk, as it can interfere with mobility. The hand, forearm, or scalp (if necessary) are preferred sites.
B. Using a 24-gauge catheter is the correct choice, as smaller-gauge catheters (24- to 26-gauge) are appropriate for infants to minimize trauma and facilitate proper IV access.
C. Changing the IV site every 3 days is a general guideline for adults, but in infants, the site should be assessed frequently and changed as needed based on signs of infiltration or complications.
D. Covering the insertion site with an opaque dressing is incorrect because a transparent dressing is preferred to allow for continuous assessment of the site for complications such as infiltration or phlebitis.