What is considered a late sign of increased intracranial pressure?

Nonreactive dilated pupils are indeed recognized as a late sign of increased intracranial pressure (ICP) because they indicate significant brain dysfunction or damage. When ICP rises, it can lead to deformation of the optic nerve, affecting the muscles that control pupil size and reactivity. A failure for the pupils to respond to light, especially when they become dilated and do not constrict, suggests severe compromise in brain activity, often signaling critical conditions such as herniation or substantial brain injury.

Increased ICP presents with a range of symptoms, beginning with more subtle changes such as confusion or altered mental status, which are generally regarded as earlier signs. Bradycardia, or a slow heart rate, can also occur as ICP escalates, particularly in the context of Cushing's triad, which represents a classic response to severe brain injury or significant pressure changes. However, both confusion and bradycardia reflect earlier responses of the body to the rising pressure, whereas nonreactive dilated pupils indicate a much more advanced stage of increased ICP.

Thus, nonreactive dilated pupils serve as a clinical alert for healthcare providers that the patient is in a critical state, necessitating immediate intervention to prevent further neurological deterioration.