A brain hemorrhage, also called a brain bleed, is an extremely dangerous situation. Whether caused by an external accident or trauma, a stroke or another medical condition, it disrupts the normal flow of blood in the brain and can quickly lead to the death of brain cells.
What Is a Brain Hemorrhage?
Brain hemorrhages are often described by where in the brain they occur, says the American Stroke Association. A subarachnoid hemorrhage is bleeding between the brain and skull that causes blood to accumulate on the surface of the brain, explains Cleveland Clinic. An intra-cerebral hemorrhage is a broken blood vessel within the brain, says the stroke association.
"Bleeding can happen outside the brain," says David Weintraub, MD, a neurosurgeon and director of functional neurosurgery at North Shore University Hospital in Manhasset, New York. This could result from a fall, which he says is very common among the elderly. "It can start as a small bleed, but can become bigger over time and require treatment."
More serious trauma causes bleeding in the brain. The danger of this type of injury is that it may not cause symptoms right away, but could become fatal days or weeks later, Dr. Weintraub says.
Bleeding also can result from a weakened blood vessel inside the brain that ruptures, or what's called a hemorrhagic stroke, according to the American Stroke Association. Strokes are the leading cause of disability and the fifth-leading cause of death in the United States. However, strokes caused by bleeding in the brain, or hemorrhagic strokes, account for only about 13 percent of all strokes, says the stroke association.
Most strokes are caused by clots in brain vessels, called ischemic strokes, says the stroke association. Though these strokes happen most often to older people, they can occur at any age, including infancy.
Read more: Broken Blood Vessels Due to Exercise
What Follows a Brain Bleed?
Regardless of the cause of the bleeding, a cascade of events follows a brain hemorrhage.
The loss of brain cells. To function normally, the brain needs a constant supply of blood and all the oxygen and nutrients it carries, explains the National Heart, Lung, and Blood Institute (NHLBI). The brain can't store oxygen or the glucose that feeds brain cells. Blood leaking into brain tissue means those nutrients don't get to brain cells. When this happens, cells starve and die.
Increased intracranial pressure. Bleeding in the brain causes pressure in the brain to increase. As the pressure increases, oxygen is decreased and the brain swells. Swelling further cuts off blood flow to the brain. In the case of a subarachnoid hemorrhage in particular, blood mixes with cerebrospinal fluid and fills the area between the brain and skull, causing pressure in the brain to rise (it's a contributor to a sudden headache), according to Harvard Health Publishing. If the rise in intracranial pressure can't be controlled, death from brain bleed can result.
Altered neurological function. A brain hemorrhage can cause a decreased level of consciousness, ranging from confusion to unconsciousness to coma, visual disturbances and weakness or loss of motor function, says Aurora Health Care.
Vasospasm. This is the narrowing and constriction of remaining blood vessels. As vasospasm worsens, the tissue in the area surrounding the broken blood vessel is also starved of oxygen and nutrients, worsening brain damage, according to a September 2011 report in Translational Stroke Research.
Spasms. In the days after the bleeding, clotting can cause the arteries near the affected area to spasm, which can further damage brain tissue, according to Harvard Health.
Know the Symptoms of a Brain Bleed
Bleeding in the brain can cause a variety of symptoms, depending on where the bleed is. In general, they include sudden weakness, numbness or paralysis of the face, arm or leg, particularly on one side of the body, says NHLBI. It can also cause a severe headache that comes on suddenly.
Difficulty swallowing or blurred vision can happen as well, as can loss of balance or coordination, NHLBI points out. Slurred speech and difficulty understanding speech as well as problems writing and reading are possible. Also, changes in the level of consciousness or alertness are common and can appear as confusion, sleepiness, stupor, lethargy, or even coma.
Any bleeding inside the skull or brain is a medical emergency that requires immediate medical attention at a hospital emergency room.
Is This an Emergency?
- David Weintraub, MD, director of functional neurosurgery, North Shore University Hospital, Manhasset, New York
- American Stroke Association: “Hemorrhagic Stroke”
- Harvard Health Publishing: “Subarachnoid Hemorrhage"
- Harvard Health Publishing: “Hemorrhagic Stroke”
- Cleveland Clinic: "Subarachnoid Hemorrhage"
- American Stroke Association: "Ischemic Stroke (Clots)"
- National Heart, Lung, and Blood Institute: "Stroke"
- Aurora Health Care: "Brain Hemorrhage"
- Translational Stroke Research: "Hyperbaric Oxygen for Cerebral Vasospasm and Brainn Injury Following Subarachnoid Hemorrhage"