Stroke, which occurs due to stopping of blood supply to the brain is often due to clot formation or bleeding in or around the brain. Clot formation in the arteries of brain occurs in ischemic stroke, while bleeding in or around the brain occurs in hemorrhagic stroke. Hemorrhagic strokes are comparatively less commonly seen and usually account for around 15% cases of stroke, but can cause death in about 40% of deaths due to stroke.
Hemorrhagic strokes are a result of rupture of a weak blood vessel, causing bleeding in the brain. Sometimes, bleeding can occur in the surrounding tissue, which can exert pressure on the brain. This can lead to decreased blood supply to some areas in the brain and damage to brain tissue, leading to a hemorrhagic stroke.
Types of Hemorrhagic Stroke
Hemorrhagic stroke is mainly classified into two types:
- Intracerebral Hemorrhage – This is the commonest type of hemorrhagic stroke. In intracerebral hemorrhage, a blood vessel ruptures or bursts and bleeds into the brain tissue. The brain cells and tissue die resulting in damage to the part of the brain where bleeding occurs.
- Subarachnoid Hemorrhage – This occurs when bleeding from a blood vessel occurs in to the space in between the brain and the surrounding tissue. This space is called subarachnoid space, hence the name subarachnoid hemorrhage.
Causes of Hemorrhagic Stroke
Hemorrhagic stroke is caused due to bleeding in the brain tissue or in the tissues around the brain. The common causes of bleeding in and around the brain includes
- Aneurysm – This occurs when a weakened part of a blood vessel get enlarged, called as ballooning. If it is not attended to at the right time, the weakened part continues to weaken, causing thinning of the vessel wall until it ruptures and bleeds into the brain tissue. This causes intracerebral hemorrhage leading to hemorrhagic stroke. Aneurysm and resulting hemorrhagic stroke can occur due to high blood pressure.
- Arteriovenous malformation (AVM) – It is a congenital condition, in which the blood vessels are abnormally formed or they are twisted in an abnormal manner. It usually affects the arteries and veins in the brain or spine. This affects the blood flow to the brain, also these blood vessels can rupture and cause bleeding into the brain. When blood vessels in the brain are malformed, it can result into intracerebral hemorrhage, while if the blood vessels in the surrounding tissue are involved, it results in subarachnoid hemorrhage, both resulting into hemorrhagic stroke.
Other Causes of Hemorrhagic Stroke Include:
- Head injury
- Hypertension or high blood pressure,
- Bleeding disorders
- Amyloidosis, in which a protein gets built up in the arteries of brain and cause easy bleeding.
- Medicines like blood thinners, taken for treatment as anticoagulant therapy, thrombolytic therapy or for treating ischemic stroke.
Some risk factors that increase the risk of hemorrhagic stroke include:
- Aging process
- High blood pressure
- Previous history of stroke
- Smoking and alcohol consumption
- Substance or Drug abuse
Symptoms of Hemorrhagic Stroke
Hemorrhagic stroke may vary in its presentation and symptoms from person to person and also depends on the type of hemorrhage.
Intracerebral hemorrhage can present with severe headache, weakness or numbness in arms, face or legs, especially on one side, sudden nausea, vomiting, confusion and sometimes loss of consciousness. Seizures may also occur if the stroke has resulted from congenital malformation (AVM).
Subarachnoid hemorrhage may show symptoms of headache. Sudden, severe headache, nausea, vomiting, stiffness in the neck, sensitivity to light and loss of consciousness may be seen.
In either of types of hemorrhagic stroke, changes in level of alertness, difficulty in speech, swallowing problems, coordinated movements of hands and legs, difficulty in writing and reading, balance problems, changes in vision, blurring or loss of vision may also be noted.
Treatment of Hemorrhagic Stroke
Diagnosis is based on clinical examination and neurological assessment. Investigations like CT scan and MRI of brain help to reveal bleeding in and around the brain. Other tests like blood counts and clotting studies may be done. Cerebro-spinal fluid (CSF) may be examined, if required. Advanced tests to diagnose congenital malformations may be done.
Treatment for hemorrhagic stroke needs emergency medicines in order to prevent worsening of the situation or else it can be fatal. The aim of treatment for hemorrhagic stroke is to control bleeding and reduce the pressure caused by bleeding in the surrounding tissue.
Medications used to control bleeding are administered in people who have suffered from hemorrhagic stroke. In case, hemorrhagic stroke has resulted from consumption of blood thinners, medicines are given to counteract the effect. Additionally, anti-convulsants, anti-hypertensive drugs and diuretics to reduce intracranial pressure are used.
Recovery from Hemorrhagic Stroke
Recovery from hemorrhagic stroke depends on the severity of stroke, cause and amount of bleeding and the damage caused to the brain tissue. Rehabilitation is required in most cases, which helps to restore lost functions and work towards regaining abilities to the best possible. Many patients spend weeks to months before they are able to perform their functions.
Prognosis and Survival in Hemorrhagic Stroke
Prognosis after a hemorrhagic stroke depends on brain damage and emergency medical treatment received at the time of stroke. The survival from a hemorrhagic stroke is more difficult than an ischemic stroke. In most cases of hemorrhagic stroke, those who receive prompt medical treatment have better chances of survival, although some may need assistance in their regular activities.