Subarachnoid Hemorrhage
A facial pain disorder causing sudden, severe, electric-shock-like pain in the face, often triggered by light touch, and usually caused by a blood vessel pressing on the trigeminal nerve.
Quick Answer
A subarachnoid hemorrhage is bleeding into the subarachnoid space, the fluid-filled area surrounding the brain. It is most often caused by a ruptured brain aneurysm and is a life-threatening emergency. The classic symptom is a sudden, extremely severe headache, often described as the worst of one’s life. Emergency care aims to secure the source of bleeding, manage complications such as vasospasm, and prevent rebleeding.
Key Takeaways
- Subarachnoid hemorrhage is bleeding into the space around the brain.
- A ruptured aneurysm is the most common cause.
- The hallmark is a sudden, extremely severe (thunderclap) headache.
- It is a medical emergency requiring immediate care.
- Treatment secures the bleeding source and manages complications like vasospasm.
AT A GLANCE
| What it is | Bleeding into the space surrounding the brain |
|---|---|
| Most common cause | Ruptured brain aneurysm |
| Hallmark symptom | Sudden, worst-ever (thunderclap) headache |
| Urgency | Life-threatening emergency: call emergency services now |
| Diagnosis | CT of the brain, sometimes lumbar puncture, then angiography |
| Treatment | Securing the aneurysm and managing vasospasm and pressure |
Symptoms
The defining symptom is a sudden, severe headache that reaches maximum intensity within seconds, often called a thunderclap headache and frequently described as the worst headache of one’s life. It may be accompanied by neck stiffness, nausea and vomiting, sensitivity to light, brief loss of consciousness, seizure, or neurological deficits.
Some people experience a warning or sentinel headache days before a major bleed. Any sudden, severe, unusual headache, especially one unlike previous headaches, should be treated as an emergency and evaluated immediately.
Common Warning Signs
- Sudden, worst-ever headache reaching peak within seconds
- Neck stiffness or pain
- Nausea and vomiting
- Sensitivity to light
- Brief loss of consciousness or seizure
When to Seek Care Promptly
- Any sudden thunderclap headache: call emergency services now
- Severe headache with neck stiffness
- Headache with loss of consciousness or seizure
- New neurological weakness with headache
- A severe headache unlike any before
Diagnosis
A CT scan of the brain is the first test and detects most subarachnoid hemorrhages, especially when performed soon after symptoms begin. If the CT is negative but suspicion remains high, a lumbar puncture may be done to look for blood in the cerebrospinal fluid.
Once a subarachnoid hemorrhage is confirmed, angiography, whether by CT, MRI, or catheter, identifies the source, most often an aneurysm, and defines its anatomy to plan treatment. Rapid diagnosis is essential because rebleeding and other complications can develop quickly.
Treatment
The immediate priority is to secure the source of bleeding to prevent a rebleed, which is especially dangerous. When an aneurysm is responsible, it is treated by endovascular coiling or flow diversion from inside the vessel, or by microsurgical clipping, with the choice based on the aneurysm’s anatomy.
Beyond securing the aneurysm, care in a neurological intensive care unit manages complications, including cerebral vasospasm, a narrowing of arteries that can occur in the days after the bleed and reduce blood flow, as well as hydrocephalus and pressure inside the skull. At Atlantic Brain and Spine, the neurovascular team coordinates this complex, time-sensitive care.
The Diagnosis-to-Treatment Pathway
1. Recognize and call
A sudden worst-ever headache prompts an emergency call.
2. Emergency CT
Imaging detects the hemorrhage; lumbar puncture is used if needed.
3. Angiography
Vascular imaging identifies the aneurysm or other source.
4. Secure the source
Coiling, flow diversion, or clipping prevents rebleeding.
5. Neuro-ICU care
Close monitoring manages pressure and complications.
6. Vasospasm management
Arterial narrowing in the following days is watched and treated.
7. Recovery and rehabilitation
Ongoing care supports recovery after stabilization.
Frequently Asked Questions
The most common cause is a ruptured brain aneurysm. Other causes include head trauma, vascular malformations, and, less often, other vascular conditions. Because a ruptured aneurysm can rebleed and is life-threatening, prompt diagnosis and treatment are essential.
The classic headache is sudden and extremely severe, reaching maximum intensity within seconds, and is often described as the worst headache of one’s life. It differs from ordinary headaches in its abrupt onset and severity, and it should be treated as an emergency.
When an aneurysm is responsible, it is secured either from inside the blood vessel with coiling or flow diversion, or from outside with microsurgical clipping. Securing the aneurysm quickly is critical to prevent a rebleed. The approach is chosen based on the aneurysm’s size, shape, and location.
Vasospasm is a narrowing of brain arteries that can develop in the days following a subarachnoid hemorrhage, reducing blood flow and risking a secondary stroke. It is a major reason patients are monitored closely in intensive care after the bleed, so it can be detected and treated early.
No, but a ruptured aneurysm is the most common cause. Trauma and vascular malformations can also cause it, and in some cases no source is found on initial imaging. Angiography is used to search for the source and guide treatment.
Recovery varies widely and depends on the severity of the initial bleed and any complications. Some people recover well, while others have lasting effects. Care in a specialized neurovascular and neurocritical care setting, followed by rehabilitation, offers the best chance of recovery.
Specialists Who Treat Subarachnoid Hemorrhages
Your care is provided by Atlantic Brain and Spine's neurovascular team, including fellowship-trained cerebrovascular and endovascular neurosurgeons.
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