What is Subarachnoid Hemorrhage? Symptoms, Causes, & Treatment

A subarachnoid hemorrhage is bleeding that occurs in the space between your brain and the thin tissues that cover it. This space, called the subarachnoid space, normally contains cerebrospinal fluid that cushions and protects your brain.

When blood enters this protective space, it can create dangerous pressure on your brain tissue. While this condition is serious and requires immediate medical attention, understanding what happens can help you recognize the warning signs and seek prompt care.

What is subarachnoid hemorrhage?

Subarachnoid hemorrhage occurs when an artery near the surface of your brain bursts and bleeds into the subarachnoid space. Think of it like a leak in the plumbing around your brain's protective cushioning system.

This bleeding disrupts the normal flow of cerebrospinal fluid and can increase pressure inside your skull. The condition affects about 10 to 15 people per 100,000 each year, making it relatively uncommon but requiring urgent treatment when it does occur.

There are two main types: traumatic subarachnoid hemorrhage from head injuries, and spontaneous subarachnoid hemorrhage that happens without trauma. Most spontaneous cases result from ruptured brain aneurysms.

What are the symptoms of subarachnoid hemorrhage?

The most characteristic symptom is an extremely severe headache that comes on suddenly. People often describe this as "the worst headache of my life" or like being "struck by lightning."

This intense headache typically reaches its peak within seconds to minutes, which is different from other types of headaches that build up gradually. The pain often spreads to your neck and may be accompanied by nausea and vomiting.

Other common symptoms you might experience include:

• Sudden neck stiffness and pain
• Sensitivity to bright lights
• Nausea and vomiting
• Confusion or altered mental state
• Drowsiness or loss of consciousness
• Seizures
• Weakness or numbness in parts of your body

Some people experience warning symptoms days or weeks before a major bleed. These warning signs, called sentinel headaches, might include unusual headaches, neck pain, or brief episodes of confusion.

In rare cases, you might have vision problems, difficulty speaking, or sudden behavioral changes. These symptoms can vary depending on which part of your brain is affected by the bleeding.

What causes subarachnoid hemorrhage?

The most common cause of spontaneous subarachnoid hemorrhage is a ruptured brain aneurysm. An aneurysm is a weak, bulging spot in the wall of an artery that can burst under pressure.

About 85% of spontaneous subarachnoid hemorrhages come from ruptured aneurysms. These aneurysms often develop at branch points where arteries split, particularly in the circle of Willis at the base of your brain.

Other causes that can lead to this type of bleeding include:

• Arteriovenous malformations (abnormal tangles of blood vessels)
• Blood vessel inflammation or infection
• Bleeding disorders or blood-thinning medications
• Certain brain tumors
• Cocaine or other stimulant drug use
• Severe head trauma from accidents or falls

In rare instances, the bleeding might result from reversible cerebral vasoconstriction syndrome, where brain arteries suddenly narrow and then return to normal. Sometimes, despite thorough investigation, doctors cannot identify a specific cause.

When to see a doctor for subarachnoid hemorrhage?

You should seek emergency medical care immediately if you experience a sudden, severe headache unlike any you've had before. This is especially urgent if the headache reaches maximum intensity within seconds or minutes.

Call 911 right away if you or someone else has a thunderclap headache along with neck stiffness, vomiting, confusion, or loss of consciousness. These combinations of symptoms require immediate evaluation.

Don't wait or try to "tough it out" if you experience warning signs like unusual headaches, brief episodes of confusion, or sudden changes in vision or speech. Even if symptoms seem to improve, they could signal a small bleed that might lead to a larger one.

What are the risk factors for subarachnoid hemorrhage?

Several factors can increase your likelihood of developing this condition. Age plays a role, with most cases occurring in people between 40 and 60 years old, though it can happen at any age.

Women have a slightly higher risk than men, particularly after menopause. This may be related to hormonal changes that affect blood vessel walls over time.

Lifestyle and medical factors that increase your risk include:

• High blood pressure
• Smoking tobacco
• Heavy alcohol consumption
• Family history of brain aneurysms
• Certain genetic conditions like polycystic kidney disease
• Previous head trauma
• Use of stimulant drugs like cocaine

Some rare genetic conditions can also increase your risk, including Ehlers-Danlos syndrome, Marfan syndrome, and neurofibromatosis type 1. Having a family member with a brain aneurysm may warrant screening discussions with your doctor.

What are the possible complications of subarachnoid hemorrhage?

Subarachnoid hemorrhage can lead to several serious complications that require careful monitoring and treatment. The most immediate concern is increased pressure inside your skull from the bleeding.

Rebleeding is one of the most dangerous early complications, occurring in about 20% of cases within the first two weeks if the aneurysm isn't treated. This second bleed is often more severe than the first.

Common complications you might face include:

• Vasospasm (narrowing of brain arteries leading to stroke)
• Hydrocephalus (fluid buildup in the brain)
• Seizures
• Blood clots in other parts of your body
• Heart rhythm problems
• Lung complications
• Electrolyte imbalances

Vasospasm typically occurs 3 to 14 days after the initial bleed and can cause stroke-like symptoms. Hydrocephalus might develop when blood blocks the normal drainage of cerebrospinal fluid.

Long-term complications can include cognitive changes, memory problems, difficulty concentrating, mood changes, and in some cases, permanent neurological deficits. However, many people do recover well with proper treatment and rehabilitation.

How is subarachnoid hemorrhage diagnosed?

Diagnosis typically begins with a CT scan of your head, which can detect bleeding in about 95% of cases when performed within 24 hours of symptom onset. This quick scan helps doctors confirm the presence of blood in the subarachnoid space.

If the CT scan doesn't show bleeding but your symptoms strongly suggest subarachnoid hemorrhage, your doctor might perform a lumbar puncture (spinal tap). This involves taking a small sample of cerebrospinal fluid to check for blood cells.

Once bleeding is confirmed, additional tests help identify the source:

• CT angiography to visualize blood vessels
• MRI and MRA (magnetic resonance angiography)
• Cerebral angiography (the gold standard for detailed vessel imaging)
• Digital subtraction angiography

Your medical team will also perform neurological examinations to assess your mental status, reflexes, and motor function. They'll monitor your vital signs closely and may use scales like the Glasgow Coma Scale to track your condition.

What is the treatment for subarachnoid hemorrhage?

Treatment begins immediately with stabilizing your condition and preventing complications. You'll likely be admitted to a neurological intensive care unit for close monitoring and specialized care.

The primary goal is to stop the bleeding and prevent rebleeding. For aneurysms, this typically involves either surgical clipping or endovascular coiling, both of which seal off the aneurysm to prevent further bleeding.

Your treatment plan may include:

• Medications to prevent vasospasm
• Blood pressure management
• Pain control
• Anti-seizure medications if needed
• Treatment for hydrocephalus with drainage procedures
• Supportive care for heart and lung function

Surgical clipping involves placing a small metal clip across the neck of the aneurysm during open brain surgery. Endovascular coiling uses a catheter to place tiny coils inside the aneurysm, causing it to clot and seal off.

Your medical team will also focus on preventing and treating complications like vasospasm with medications such as nimodipine, which helps keep brain arteries open and maintain blood flow.

How to manage recovery from subarachnoid hemorrhage?

Recovery from subarachnoid hemorrhage is often a gradual process that requires patience and comprehensive care. Your medical team will create a personalized rehabilitation plan based on your specific needs and the extent of any complications.

Physical therapy can help you regain strength and coordination if you experienced weakness or balance problems. Occupational therapy focuses on relearning daily activities and adapting to any persistent changes in function.

During your recovery, you can support your healing by:

• Following all medication schedules exactly as prescribed
• Attending all follow-up appointments
• Participating actively in rehabilitation programs
• Getting adequate rest and sleep
• Eating a healthy, balanced diet
• Avoiding smoking and excessive alcohol
• Managing stress through relaxation techniques

Many people experience fatigue, headaches, or difficulty concentrating during recovery. These symptoms often improve with time, but it's important to communicate with your healthcare team about any concerns.

Emotional support is crucial during recovery. Consider joining support groups or working with counselors who understand the challenges of recovering from brain injuries.

How should you prepare for your doctor appointment?

If you're scheduling a follow-up appointment after treatment, preparation can help you make the most of your time with your healthcare provider. Write down any symptoms you've noticed since your last visit, including headaches, changes in thinking, or physical symptoms.

Bring a complete list of all medications you're taking, including dosages and how often you take them. Include over-the-counter medications, supplements, and any herbal remedies.

Consider bringing a family member or friend to help you remember information and ask questions. They can also provide valuable observations about changes in your condition or behavior.

Prepare specific questions about your recovery progress, activity restrictions, warning signs to watch for, and when you might return to work or normal activities. Don't hesitate to ask about anything that concerns you.

What's the key takeaway about subarachnoid hemorrhage?

Subarachnoid hemorrhage is a serious medical emergency that requires immediate treatment, but with prompt care, many people can recover well. The key is recognizing the warning signs and seeking help quickly.

Remember that a sudden, severe headache unlike any you've experienced before should always prompt immediate medical attention. Early treatment significantly improves outcomes and reduces the risk of complications.

While the condition can be frightening, advances in medical care have improved survival rates and recovery outcomes. Your healthcare team will work with you to provide the best possible care and support throughout your recovery journey.

Focus on following your treatment plan, participating in rehabilitation, and maintaining open communication with your medical team. With proper care and time, many people go on to live fulfilling lives after experiencing subarachnoid hemorrhage.