Which symptom might indicate a patient with dangerously high blood pressure is in need of immediate medical attention?

Visual changes are a critical symptom that could indicate a patient is experiencing dangerously high blood pressure, particularly in the context of hypertensive emergencies. High blood pressure can lead to complications such as hypertensive retinopathy or even impaired blood flow to the optic nerve, resulting in changes to visual acuity or other visual disturbances. These symptoms signal that the hypertension may be affecting vital organs, including the brain and eyes, and urgent medical evaluation and intervention are necessary to prevent further complications, such as stroke or permanent vision loss.

In contrast, symptoms like a dry cough, increased appetite, and muscle soreness are generally not associated with acute hypertensive crises and may suggest other non-urgent conditions or responses. These symptoms do not have the same immediate implications for severe hypertension, making them less critical for urgent medical attention.