Which condition is indicated by a sudden change in a child’s vital signs, including bradycardia and hypertension?

A sudden change in a child's vital signs that includes bradycardia (a slower than normal heart rate) and hypertension (high blood pressure) is indicative of increased intracranial pressure (ICP). When the pressure inside the skull rises, it can lead to various physiological responses in the body due to the limited space in the skull for the brain and cerebrospinal fluid.

As ICP increases, the body attempts to maintain cerebral perfusion by constricting the blood vessels, resulting in hypertension as the body compensates for the reduced blood flow to the brain. The slowing of the heart rate, or bradycardia, can occur as a reflexive response when ICP reaches a critical level, activating the brain’s protective mechanisms.

In contrast, conditions like respiratory infection and shock typically cause an increased heart rate (tachycardia) rather than bradycardia. Heart failure may present with a variety of vital sign changes and usually does not typically cause a combination of bradycardia and hypertension as seen in increased ICP. Therefore, the combination of bradycardia and hypertension is a hallmark sign of increased intracranial pressure, making it the most fitting diagnosis in this scenario.