What is the most appropriate action for a nurse to take when a crying toddler has a blood pressure measurement of 120/70 mm Hg?

In situations like this, crying can significantly affect a child's blood pressure readings due to stress and anxiety, leading to elevated values that may not accurately reflect their baseline health. Therefore, the most appropriate action is to calm the toddler and then retake the blood pressure measurement. This approach helps ensure that the reading reflects the child's true physiological state rather than the temporary emotional response they are exhibiting.

When a child is upset, their vital signs, including blood pressure, can fluctuate. By addressing their distress first, the nurse is more likely to obtain a valid measurement that can be used for accurate assessment and clinical decision-making. This is a standard practice in pediatric nursing, where understanding the impact of emotional states on physiological measurements is crucial.

The other options do not prioritize obtaining an accurate blood pressure reading under calmer conditions, which is essential for proper evaluation of the child's cardiovascular status.