SAH is a type of bleeding inside the head caused by an abnormality of an artery, usually an aneurysm. An aneurysm is an abnormal swelling in the wall of an artery, like a small balloon in a water-hose, which can suddenly rupture causing bleeding.

What are risk factors for having a brain aneurysm?

The first and the main one is the female gender, as women have more aneurysms than men. Also, aneurysms tend to cause trouble around menopausal age. Having a first degree relative is also a risk factor for aneurysms.

 

What are the symptoms of SAH?

The main symptom of SAH is sudden onset of severe headache, like a thunderclap. Patients usually report it as the worst headache of their life. Other common associated symptoms are nausea, vomiting, seizure, any other stroke like symptom, and loss of consciousness. SAH is one of the most serious conditions requiring urgent transfer of the patient to an emergency room.

 

How is SAH diagnosed?

If suspected by its typical history (sudden severe headache), it is diagnosed by a brain scan, usually a CT scan without contrast. Sometimes, the CT scan is normal or does not reveal the sign of bleeding. In such cases, if the history is strongly suggestive, more investigations like a lumbar puncture or an MRI of brain can be helpful. The lumbar puncture is done to find any sign of bleeding in the spinal fluid, while an MRI can be more sensitive to bleeding than a CT scan. 

Once SAH is diagnosed, the next step is to find its exact cause or the location of the leaky aneurysm. This requires imaging of the brain’s arteries, which can be achieved by a test called CTA of brain, which is a CT scan of brain with contrast. If for some reason this cannot be done, e.g., in a patient with allergy to the CT dye, an MRA of brain can help. In some cases, the diagnosis is made by a conventional angiogram, which is performed by inserting a catheter in the brain’s blood vessels, injecting a dye, and taking Xray pictures (the so-called conventional angiogram).

 

How is SAH treated?

SAH is a life-threatening condition. Despite all the available facilities and technology, some patients never make to the emergency room alive. Rapidity of action, stabilizing the patient, and transfer to a suitable facility are the key life-saving measures. As soon as patient arrives in ER, investigations are quickly done to make the diagnosis. Patient’s ABCs (airway, breathing, and circulation) are stabilized, and a quick decision is made for a quick transfer to a proper facility, or an intervention if available. Depending upon the size and location of an aneurysm, a decision is made for an appropriate intervention. Most aneurysms nowadays are handled by doctors specializing in catheter-based treatment, or neuro-interventionalists. They use a technique called “coiling” to permanently block flow of blood in an aneurysm. A coiled mesh is inserted in the aneurysm, which makes blood to clot to help seal the aneurysm. For most patients, it is a relatively painless process (done under conscious sedation or under anesthesia) and can help to eliminate a deadly health risk. Not every aneurysm can be treated in this manner, for example, an aneurysm with a wide neck or in a difficult to reach location may require an open brain surgery. Patients treated with surgery are at much higher risk due to complications associated with surgery.

 

What are the complications of SAH?

If an aneurysm is timely and appropriately taken care of, there may not be any long-term complications. But many patients are not that lucky. Common long-term complications are cognitive difficulties, weakness, unsteadiness, and seizure disorder.

 

Where may I find more information about SAH?

American Academy of Neurology

American Stroke Association

American Association of Neurological Surgeons