Blackouts and Neck Pain: Causes, Conditions & When to See a Doctor

Aortic dissection is a life-threatening emergency in which the inner layer of the aorta tears, allowing blood to surge between the vessel walls. It typically presents with sudden, severe tearing or ripping chest or back pain radiating to the back, and requires immediate surgical evaluation.

Subarachnoid hemorrhage is bleeding into the subarachnoid space surrounding the brain, most often caused by a ruptured cerebral aneurysm. It classically presents with a sudden, severe thunderclap headache described as the worst headache of life, accompanied by nausea, vomiting, and neck stiffness.