A 38-week-gestation infant weighing 4.5 kg exhibits tremors two hours after birth. What should the nurse do first?

In this scenario, the appropriate initial action for the nurse is to obtain a heelstick glucose level. This is critical because the infant, who is full-term and has a birth weight that is above the typical average, is exhibiting tremors shortly after birth. Tremors in a newborn can often be indicative of hypoglycemia, which is a common concern in infants, especially when they display signs such as jitteriness or tremors.

Determining the blood glucose level promptly allows for the identification of potential hypoglycemia as the cause of the tremors. If hypoglycemia is confirmed, timely treatment can be initiated based on the result. This assessment takes precedence over other actions since it addresses a possible immediate concern that could threaten the infant's health if not managed quickly.

While checking vital signs, performing a neurological assessment, or administering glucose are also important nursing actions, they are secondary to first confirming whether hypoglycemia is present. Identifying the actual cause of the tremors through glucose testing is essential in guiding further treatment and interventions.