Subarachnoid Hemorrhage

Also known as Subarachnoid Bleed

Subarachnoid hemorrhage involves bleeding in the space between the brain and the overlying subarachnoid lining. This space is known as the subarachnoid space. The bleeding can be very fast and can result in death within hours of getting the subarachnoid hemorrhage.

The cause of a subarachnoid bleed includes a bleeding disorder that causes spontaneous bleeding between the layers of the brain and connective tissue. It can also be caused by an arteriovenous malformation or from a cerebral aneurysm. Head injuries can disrupt blood vessels in the subarachnoid space. It can happen if you use blood thinners or happen just as a result of an idiopathic, non-traumatic bleed. The most common cause of a subarachnoid hemorrhage occurs in the elderly who have fallen and have struck their head during the fall. In the youth, the most common cause of subarachnoid bleeding is a motor vehicle accident.

Subarachnoid hemorrhage is not common. It occurs in 10-15 percent out of a thousand individuals and is due to a rupture of a cerebral aneurysm most commonly in those between the ages of 20-60. Women get the hemorrhage slightly more commonly than do men.

Risk factors to subarachnoid hemorrhage include having an aneurysm in other types of blood vessels, having fibromuscular dysplasia, which is a connective tissue disorder affecting the outside of walls of the blood vessels, having high blood pressure, smoking history or a history of polycystic kidneys. If you have a strong family history of aneurysms, your risk of bleeding from an aneurysm yourself is greater than average.

Symptoms of subarachnoid hemorrhage are usually severe and life threatening. People with a subarachnoid hemorrhage usually experience the "worst headache of their life", usually worse in the back of the head. There is usually a decreased level of consciousness associated with a loss of feeling or movement to a part of the body. There are personality changes and alterations in mood, including irritability and confusion. Muscle aches, including shoulder and neck pain, are also common along with nausea and vomiting. Seizures can happen and the individual can often not tolerate light. There is usually a stiff neck and double vision or vision problems.

Rarely, there can be differing sizes of pupils, eyelid drooping and arching of the back with subarachnoid hemorrhage.

Doctors need to diagnose a subarachnoid hemorrhage relatively quickly so as to proceed with treatment as soon as possible. A complete neurological examination and physical examination can show some of the symptoms as noted above. The patient can be in a deep coma. Neurological deficits can be noted on examination. A CT scan of the head will show blood in the subarachnoid space and pressure on the brain. There can be a spinal tap as well, which will show blood in the cerebrospinal fluid. A CT angiography exam can show the presence or absence of an aneurysm. CT angiography is the best test of a subarachnoid hemorrhage.

MRI scanning can show the same thing as a CT scan of the head and, in some cases, an ultrasound done through the skull can show blood vessel spasms and areas of bleeding.

The treatment of subarachnoid bleeding must be fast in order to save one's life. The idea is to save your life as well as to prevent brain damage as a result of pressure on the brain. Surgery may be required in order to clip off an aneurysm and prevent further bleeding. If this cannot be done, a craniotomy can be done to relieve pressure on the brain. There is a special procedure called an endovascular coiling that clots the blood within the aneurysm using a minimally invasive technique.

Patients with subarachnoid hemorrhage need to be supported form a life support standpoint. They may need intubation and control of blood pressure in order to decrease the bleeding. Mannitol and steroids are used to decrease the pressure on the brain. A tube may need to be inserted into the skull in order to drain excess blood from the brain. Anti-anxiety medications and pain killers are used to control the common agitation and pain associated with the condition. Medications against seizures are also often given as the seizure rate is high.