Subarachnoid hemorrhage is bleeding in subarachnoid space of brain. Subarachnoid space is an area between the brain and tissue that is surrounding the brain. It is the space in which the cerebro spinal fluid circulates. The main function of subarachnoid space is to provide cushion to the brain from injury and jerks. Hemorrhage or bleeding in subarachnoid space is caused either by injury to the brain and skull or due to spontaneous rupture of aneurysm of blood vessel in brain. Aneuryrsm is abnormal thinning and bulging of blood vessel.
Subarachnoid hemorrhage although rare is a serious condition that can lead to stroke, coma and death of a person. Nearly 30000 people in United States are affected by subarachnoid hemorrhage caused due to aneurysm rupture. Subarachnoid hemorrhage needs to be treated as an emergency. Early surgical and vascular repair of ruptured aneurysm can improve the chances of survival of the patient.
What Are The Causes Of Subarachnoid Hemorrhage?
Subarachnoid hemorrhage occurs when there is bleeding inside the subarachnoid space. The bleeding can develop from the vessels in brain. There are two main causes in which hemorrhage may occur. Firstly trauma to brain due to severe injury or fall can damage the brain vessel which may break and cause bleeding. Another important cause is aneurysm in brain. Aneurysm is a condition in which the wall of blood vessel becomes weak and bulges. At some time the wall become so thin and bulges like a balloon that it gets ruptured and blood leaks out in the subarachnoid space.
Most of the time subarachnoid hemorrhage is spontaneous. One of the frequent causes is berry aneurysm. The vessels in brain are malformed and appear as a cluster of berry. After the blood leaks out in the space, it forms a clot and compresses the brain tissue. Subarachnoid hemorrhage can occur at any age, but most commonly it develops between 40 and 65 years. Risk factors increases in female, smokers, hypertensive, people using illicit drugs such as cocaine and methamphetamine and those suffering from brain aneurysm.
Signs And Symptoms Of Subarachnoid Hemorrhage
The symptoms of subarachnoid hemorrhage are spontaneous. They may develop suddenly after an injury to brain or as a result of rupture of aneurysm. Often when the patient is engaged in physical exertion like weight lifting or when there is violent bout of coughing or even during sexual intercourse, patient may hear a sudden ‘snap’ in the head which is followed by severe and excruciating headache and vomiting. Patient may collapse on the floor.
Sudden excruciating headache is typically associated with subarachnoid hemorrhage. Other signs and symptoms are as follows:
- Severe headache and vomiting.
- Severe neck pain and rigidity.
- Double vision
- Increased irritability
- Increased sensitivity to light.
- Feeling numb and paralysis all over body.
- Loss of vision
- Loss of consciousness
The symptoms and signs of subarachnoid hemorrhage depend on the location of bleeding, severity of hemorrhage, and the rapidity with which it evolves. Sudden death with massive hemorrhage is not uncommon.
Diagnosis And Treatment Of Subarachnoid Hemorrhage
For diagnosis of subarachnoid hemorrhage, the doctor will recommend following tests, besides physical examination of the patient.
- CT scan of brain
- MRI of brain
- Cerebral angiography
- Cerebrospinal fluid examination: CSF is withdrawn with the help of lumbar puncture. A needle is inserted into the lower spine to withdraw CSF. If the CSF is under raised pressure and contains more than million red blood cells per cubic millimeter in CSF, it confirms the diagnosis of subarachnoid hemorrhage.
Subarachnoid hemorrhage is a serious condition which needs emergency medical attention. It has increased mortality rate and patient often dies within first week depending on the clinical condition at the time of hemorrhage. The primary goal of treatment hence is to save the life of patient and reduce the extent of brain damage.
In the beginning patient is placed in a quiet room with head slightly elevated. All forms of physical strain are avoided such as violent coughing, straining at stool, sneezing etc. Blood pressure is monitored and controlled. To control severe headache, patient is given analgesics and sedatives.
If hemorrhage occurs due to aneurysm, surgery is performed to clip the neck of aneurysm. Certain aneurysms are treated with balloon occlusion therapy. If the patient is in coma, all necessary life support system may be needed such as artificial respiration, drainage tube, maintaining patency of airway etc.