Descripción general

La hemorragia subaracnoidea es el sangrado en el espacio entre el cerebro y la membrana que lo rodea (espacio subaracnoideo). El síntoma principal es el dolor de cabeza intenso y repentino. Algunas personas lo describen como el peor dolor de cabeza que hayan sentido. Además de tener un dolor de cabeza, algunas personas pueden experimentar:

  • Náuseas
  • Vómitos
  • Rigidez en el cuello
  • Problemas de la vista
  • Pérdida del conocimiento breve

El sangrado generalmente ocurre al romperse un bulto anormal en un vaso sanguíneo (aneurisma) en el cerebro. Algunas veces, el sangrado puede ser causado por un traumatismo, una maraña de vasos sanguíneos en el cerebro (malformación arteriovenosa) u otros problemas de salud o en los vasos sanguíneos.

Si no se trata, una hemorragia subaracnoidea puede causar un daño cerebral permanente o la muerte.

Síntomas

The most common symptom of a subarachnoid hemorrhage is a very sudden, very bad headache. The headache starts in a split second and becomes very painful right away. Some people describe it as the worst headache they have ever had.

Along with a sudden headache, symptoms may include:

  • Nausea.
  • Vomiting.
  • Stiff neck or neck pain.
  • Changes in vision.
  • Brief loss of consciousness.

When to see a doctor

A subarachnoid hemorrhage is a medical emergency.

Get immediate medical attention if you experience a very sudden, very bad headache or if you have other symptoms of a subarachnoid hemorrhage. This is especially important if you have been diagnosed with a brain aneurysm or if you have experienced a head injury.

If you're with someone who complains of a very bad headache that came on suddenly or who loses consciousness, call 911 or your local emergency number.

Causas

A subarachnoid hemorrhage may be caused by:

  • A brain aneurysm that bursts. A brain aneurysm is a bulge in a blood vessel in the brain. The aneurysm can burst and cause bleeding in the space between the brain and the tissues covering the brain, known as the subarachnoid space. A brain aneurysm is the most common cause of a subarachnoid hemorrhage.
  • Head injury. Another common cause is a head injury. A head injury from an auto accident, fall or violence can lead to a subarachnoid hemorrhage.
  • A tangle of blood vessels in the brain, known as an arteriovenous malformation. This irregular tangle of blood vessels can rupture and cause bleeding in the brain.
  • Swelling of the blood vessels, known as vasculitis. This can cause the walls of the blood vessels to thicken and narrow. Vasculitis can lead to a blood clot or an aneurysm.

Factores de riesgo

Some risk factors for a subarachnoid hemorrhage are not under your control. They include:

  • Being an older age. Most subarachnoid hemorrhages that result from an aneurysm occur in people between ages 55 and 60. Women in their 50s and 60s, in particular, have a higher risk.
  • Having a first-degree relative with a brain aneurysm. This includes a parent, child or sibling related by blood
  • Having certain health conditions. Conditions that increase the risk of a subarachnoid hemorrhage include Ehlers-Danlos syndrome, Marfan syndrome, neurofibromatosis type 1 and polycystic kidney disease.

People who have two or more first-degree relatives with brain aneurysms or who have had a subarachnoid hemorrhage can get screened.

Other risk factors for a subarachnoid hemorrhage can be avoided. They include:

  • Having high blood pressure.
  • Smoking.
  • Misusing alcohol.
  • Using drugs such as cocaine and methamphetamine.
Escrito por el personal de Mayo Clinic