Diagnosis, Medical Management, and Complications of Aneurysmal Subarachnoid Hemorrhage

Abstract

Aneurysmal subarachnoid hemorrhage (aSAH) carries significant morbidity and mortality. Although major differences in the incidence of the disease exist, the incidence of aSAH ranges from 2 to 16 per 100,000 people. Despite advancements in the treatment of patients with aSAH, 12–15% of patients will still die prior to hospital admission. The incidence of aSAH increases with age, with median age of onset >50 years of age, and is more common in women than in men. The clinical hallmark of aSAH, in an awake patient, is the complaint of the sudden onset of the “worst headache of life” (Bassi P, Acta Neurol Scand 84(4):277–81, 1991). In 10–40% of patients, this thunderclap headache is preceded 7–30 days by a warning or sentinel headache. This sentinel headache signifies a slow bleed from the aneurysmal site and carries with it a tenfold increased risk of rebleeding. Additional signs and symptoms of aSAH include nausea with or without vomiting, stiff neck, photophobia, cranial nerve palsies and other focal neurological deficits, and seizures, up to and including the loss of consciousness. Individual variation in the signs and symptoms is common leading to high incidence of misdiagnosis or delayed diagnosis. This can occur in up to 12% of patients. Patients misdiagnosed at initial presentation have a four times greater likelihood of death or significant disability at 1 year.