Haemorrhage Intracranial

Intracranial haemorrhage is a type of stroke that causes bleeding inside the skull or brain tissue, preventing oxygen from reaching your brain. This life-threatening medical emergency requires immediate treatment to prevent permanent brain damage or death.

Table of contents

• What is intracranial haemorrhage?
• Types of brain bleeds
• Symptoms
• Causes and risk factors
• Diagnosis
• Treatment options
• Outcome and recovery
• Prevention

What is intracranial haemorrhage?

Intracranial haemorrhage, also called a brain bleed or brain haemorrhage, is a type of stroke that occurs when a blood vessel in or around your brain ruptures or leaks^[1]. When this happens, blood collects or pools within your skull and brain. This creates pressure against your brain tissue, which prevents oxygen and nutrients from reaching your brain cells^[1].

Your brain relies on a network of blood vessels to deliver oxygen and nutrients. Because your brain cannot store oxygen, it needs a constant supply through these blood vessels^[1]. When a brain bleed occurs, the normal blood flow is disrupted, and the accumulating blood causes additional damage. It only takes three to four minutes for brain cells to die if they don’t receive enough oxygen^[1].

Brain bleeds account for approximately 8 to 13 percent of all strokes and carry higher rates of death and disability than ischaemic strokes (strokes caused by blocked blood vessels)^[4][7]. In the United States, more than 795,000 people experience a stroke each year^[1].

Types of brain bleeds

Healthcare providers classify intracranial haemorrhages based on where the bleeding occurs. There are two main areas where bleeding can happen: within your skull but outside of brain tissue, or inside the brain tissue itself^[1][2].

To understand the different types, it helps to know that your brain is covered by three protective membrane layers called meninges. These three membranes are the dura mater (the outermost layer), the arachnoid membrane (the middle layer), and the pia mater (the innermost layer). Bleeding can occur anywhere between these membranes or within the brain tissue itself^[1].

Bleeds outside brain tissue (extra-axial haemorrhages)

Epidural bleed: This type of bleeding occurs between the skull bone and the outermost membrane layer, the dura mater. An epidural bleed typically happens after a head injury, often involving a skull fracture that damages an underlying blood vessel, most commonly the middle meningeal artery^[1][2]. Without treatment, it can cause rising blood pressure, breathing difficulties, brain damage, or death^[3].

Subdural bleed: This bleeding happens between the dura mater and the arachnoid membrane beneath it. Subdural bleeds can develop quickly (acute), over several days or weeks (subacute), or slowly over time (chronic)^[3]. Acute subdural bleeds develop rapidly and have high mortality rates, often resulting from severe head trauma. Chronic subdural bleeds occur more slowly and are common in older adults, people taking blood thinners, or those with brain changes due to conditions like dementia^[3].

Subarachnoid bleed: This type of haemorrhage occurs between the arachnoid membrane and the pia mater, in the space surrounding the brain^[1][7]. A subarachnoid bleed is a medical emergency. It can result from head trauma or, in some cases, from a ruptured aneurysm (a bulge in a weakened blood vessel)^[3]. Many people who experience a subarachnoid haemorrhage have a sudden, severe headache, sometimes described as the worst headache of their life^[7].

Bleeds inside brain tissue (intra-axial haemorrhages)

Intracerebral haemorrhage: This is bleeding that occurs within the brain tissue itself, most commonly in areas such as the lobes, brainstem, or cerebellum^[1][2]. Intracerebral haemorrhage is the most common type of haemorrhagic stroke, accounting for about two-thirds of all brain bleeds^[7]. The most frequent cause is long-term high blood pressure, which weakens small blood vessels deep within the brain^[4].

Intraventricular haemorrhage: This bleeding occurs in the brain’s ventricles, which are hollow spaces where your body produces cerebrospinal fluid (the fluid that protects your brain and spinal cord)^[1].

Symptoms

Symptoms of intracranial haemorrhage can appear suddenly or develop gradually over time. As the bleeding continues and pressure on the brain increases, symptoms may become more severe^[3]. The specific symptoms depend on the location and size of the bleed, but common warning signs include^[1][3]:

• Sudden, severe headache
• Sudden weakness, tingling, or numbness in your face, arm, or leg, particularly on one side of your body
• Nausea and vomiting
• Confusion
• Dizziness
• Slurred speech or difficulty understanding speech
• Difficulty swallowing
• Vision problems
• Loss of balance or coordination
• Loss of movement on the side of the body opposite to the head injury

More severe symptoms may develop as blood continues to fill the brain or the space between your skull and brain. These include seizures, loss of consciousness, or feeling extremely tired^[3].

A sudden, severe headache that feels like being hit on the head—sometimes called a “thunderclap headache”—is particularly common with subarachnoid haemorrhage. If you experience this type of headache, even if it goes away on its own or with painkillers, you should call emergency services immediately^[7].

Intracranial haemorrhage is a medical emergency. If you or someone else experiences any of these symptoms, call emergency services (911 or your local emergency number) immediately.

Causes and risk factors

Common causes

The most common cause of intracranial haemorrhage is head trauma from falls, car accidents, sports injuries, or bicycle accidents^[5]. Even a mild head injury can cause a brain bleed in people who take blood thinners or aspirin, especially in older adults^[5].

For spontaneous (non-traumatic) intracerebral haemorrhage, the two main causes are^[4][9]:

Chronic high blood pressure (hypertension): Long-term high blood pressure causes changes to the small arteries deep within the brain, weakening them and making them more likely to rupture^[2][4]. High blood pressure related bleeds typically occur in younger patients and involve deep brain structures like the basal ganglia or thalamus^[9].

Cerebral amyloid angiopathy: This condition involves the buildup of a protein called amyloid in the walls of brain blood vessels, particularly those in the outer parts of the brain. This makes the vessels fragile and prone to bleeding^[4][9]. Cerebral amyloid angiopathy is more common in older people and typically causes bleeding in the outer areas of the brain (lobar haemorrhages)^[9].

Other important causes include^[4][5]:

• Brain aneurysms (weakened, bulging areas in blood vessel walls)
• Arteriovenous malformations (abnormal tangles of blood vessels)
• Blood clotting disorders or bleeding disorders
• Use of anticoagulant medicines (blood thinners)
• Brain tumours
• Bleeding into an area where a blood clot had previously blocked blood flow (haemorrhagic transformation of an ischaemic stroke)
• Use of drugs such as cocaine or amphetamines
• Liver disease
• Blood vessel inflammation (vasculitis)

Risk factors

Several factors can increase your risk of experiencing an intracranial haemorrhage^[4]:

• Age: Risk increases sharply after age 55 and doubles with each decade until age 80
• Uncontrolled high blood pressure
• Taking blood thinners or aspirin
• Previous history of stroke
• Excessive alcohol use or alcohol use disorder
• Use of recreational drugs, particularly cocaine or amphetamines
• Liver disease
• Being male (slightly more common in men)

Diagnosis

When you arrive at the hospital with symptoms suggesting a brain bleed, doctors will act quickly to diagnose the problem. A healthcare provider will first ask about your symptoms and perform a physical examination^[3].

The main diagnostic test is a computed tomography (CT) scan of your brain without contrast. This is the most important test for diagnosing intracranial haemorrhage because it can quickly show whether there is bleeding and where it is located^[2][3].

Additional tests that may be performed include^[3][11]:

• Magnetic resonance imaging (MRI) scan: This test uses magnetic fields and radio waves to create detailed images of your brain
• CT angiography (CTA): A dye is injected into your bloodstream to make blood vessels easier to see on a CT scan, helping doctors identify aneurysms or other blood vessel problems
• Angiogram: A thin tube (catheter) is inserted into an artery and guided to your brain. Dye is then injected through the catheter to show blood flow on X-rays
• Lumbar puncture (spinal tap): A sample of cerebrospinal fluid is taken from your lower back to check for blood
• Blood tests to check clotting function and other factors

Because brain bleeds can worsen quickly, repeat CT scans are often done to monitor the size of the haemorrhage. Studies show that up to 38 percent of brain bleeds expand within the first three hours, and the volume of bleeding is an important predictor of 30-day mortality^[9].

Treatment options

Treatment for intracranial haemorrhage focuses on stopping the bleeding, reducing pressure on the brain, and preventing further damage. The specific approach depends on the type, location, and size of the bleed, as well as your overall health^[3][10].

Emergency care

Initial treatment focuses on stabilizing your condition and may include^[2][12]:

• Supporting your airway and breathing, which may require a breathing tube
• Controlling blood pressure to prevent further bleeding
• Managing pressure inside your skull (intracranial pressure)
• Reversing the effects of blood-thinning medications if you are taking them
• Preventing or treating seizures
• Preventing complications such as blood clots in the legs

If you take blood thinners such as warfarin, you may need treatment to reverse the medication’s effects. Options include giving vitamin K or fresh frozen plasma to reduce the risk of further bleeding^[11][12].

Surgical treatment

Not all brain bleeds require surgery. Small haemorrhages that cause minimal symptoms may be managed without surgical intervention^[10]. However, surgery may be necessary in certain situations^[3][10]:

Traditional surgery: In some cases, open surgery may be needed to remove the accumulated blood and relieve pressure on the brain, or to repair damaged blood vessels^[3].

Catheter drainage: A long, thin tube (catheter) may be inserted through the skull and threaded through blood vessels to the affected area to drain the blood^[3].

Draining cerebrospinal fluid: Sometimes, doctors drain the fluid that surrounds the brain to create more space and reduce pressure from the accumulated blood^[3][5].

The decision about whether surgery is needed depends on several factors, including the location of the bleed, the amount of blood, how quickly symptoms are developing, and your overall health^[10].

Monitoring and supportive care

After initial treatment, you will likely be monitored closely in an intensive care unit or specialized stroke unit. Healthcare providers will watch for signs of worsening, such as increased pressure in your skull, further bleeding, or complications^[2]. Repeat imaging scans may be done to check if the bleeding has stopped or if the blood is being reabsorbed^[10].

Outcome and recovery

Intracranial haemorrhage is the most deadly type of stroke. More than one-third of patients with intracerebral haemorrhage do not survive, and only about 20 percent regain functional independence^[9]. The severity and outcome depend on the cause, location, size of the bleed, and how quickly treatment begins^[1].

Once brain cells die, they cannot regenerate. This means that damage from a brain bleed can result in permanent physical, mental, or functional disability^[1]. However, treating a brain bleed quickly leads to the best possible outcome^[1].

Recovery stages

Recovery from a brain haemorrhage typically progresses through several phases^[17][19]:

Acute recovery (first few days to weeks): During this stage, medical professionals focus on stabilizing your condition using medications, surgery if needed, and close monitoring in intensive care or stroke units. This phase concentrates on life-saving measures^[17][19].

Rehabilitation phase: Once you are stable, the focus shifts to rehabilitation. This typically includes physical therapy to help with movement, occupational therapy to regain independence in daily activities, and speech therapy if you have communication difficulties^[19]. Starting rehabilitation early—within the first 90 days, often called the “golden window”—is critical for the best outcomes due to your brain’s ability to adapt and reorganize (neuroplasticity)^[19].

Long-term recovery: This phase focuses on preventing another bleed, maintaining overall well-being, and managing any lasting effects. It includes regular follow-up visits, healthy lifestyle practices, and mental health support^[17][19].

Recovery time varies widely from person to person. While significant improvements may occur in the first few weeks, complete recovery can take much longer, and some effects may be permanent^[17].

Prevention

While some risk factors for intracranial haemorrhage cannot be changed, such as age or genetics, there are important steps you can take to reduce your risk^[18]:

Control high blood pressure: Managing your blood pressure is one of the most important ways to prevent brain haemorrhage. High blood pressure is the leading cause of spontaneous intracerebral haemorrhage. Keep your blood pressure under control through a healthy diet, regular exercise, maintaining a healthy weight, limiting salt intake, and taking prescribed blood pressure medications^[18][19].

Avoid smoking and limit alcohol: Both smoking and heavy alcohol consumption can damage blood vessels and increase blood pressure, raising your risk of brain bleeds. Quitting smoking and moderating alcohol intake can help protect your brain health^[18].

Maintain a healthy diet: Eat a balanced diet rich in fruits, vegetables, whole grains, and lean proteins. Foods high in omega-3 fatty acids (such as fatty fish), antioxidants, and B vitamins support brain health and healing^[18][19].

Exercise regularly: Aim for at least 30 minutes of moderate-intensity physical activity on most days of the week. Regular exercise improves cardiovascular health and helps control conditions that increase stroke risk^[18].

Manage other health conditions: Keep conditions such as diabetes and high cholesterol under control. Take prescribed medications as directed^[18][19].

Prevent head injuries: Wear protective gear during sports and other activities. Take precautions to prevent falls, especially if you are older or have balance problems. Use seatbelts in vehicles^[18].

Get regular check-ups: Regular visits to your healthcare provider can help monitor your overall health and identify any conditions or risk factors that increase your risk of brain haemorrhage. Follow your doctor’s recommendations for screenings and preventive care^[18].

Manage stress: Chronic stress can increase blood pressure and affect both physical and mental health. Find healthy ways to manage stress, such as meditation, yoga, or spending time with loved ones^[18].

Know the warning signs: Learn to recognize the symptoms of brain haemorrhage so you can seek immediate medical help if they occur. Quick treatment can save your life and improve your chances of recovery^[18].