Introduction
Subarachnoid haemorrhage (SAH) is a medical emergency that requires rapid recognition and management. As a junior doctor, being familiar with the signs, symptoms, and management strategies for SAH is crucial. This guide aims to provide you with practical advice on history taking, investigations, and management, drawing from authoritative sources.
History Taking: Key Questions to Ask
Onset and Nature of Headache:
"When did the headache start?"
"Was the onset sudden or gradual?"
"Can you describe the headache?"
Associated Symptoms:
"Do you have any nausea or vomiting?"
"Have you noticed any changes in your vision?"
"Do you feel light-sensitive (photophobia)?"
"Any neck stiffness or pain?"
Neurological Symptoms:
"Have you experienced any weakness, numbness, or difficulty speaking?"
"Any loss of consciousness or seizures?"
Previous History:
"Have you had similar headaches in the past?"
"Do you have a history of migraines?"
"Have you ever had any head injuries?"
Family History:
"Is there a family history of brain aneurysms or strokes?"
Medication and Lifestyle:
"Are you on any blood thinners (anticoagulants)?"
"Do you smoke or use recreational drugs?"
Investigations: What to Order and Why
Non-Contrast CT Head:
Why: The first-line investigation for suspected SAH. It is most sensitive within the first 6 hours of headache onset, detecting blood in the subarachnoid space.
What to look for: Hyper density in the basal cisterns, sulci, and fissures.
Lumbar Puncture:
Why: If the CT scan is negative but clinical suspicion remains high, a lumbar puncture should be performed. This is particularly important if more than 6 hours have passed since the headache onset.
What to look for: Xanthochromia (yellowish discoloration of the cerebrospinal fluid) is indicative of SAH.
CT Angiography (CTA):
Why: To identify the source of bleeding, such as an aneurysm. CTA is often performed after confirming SAH on a non-contrast CT or lumbar puncture.
What to look for: Vascular abnormalities like aneurysms or arteriovenous malformations.
Magnetic Resonance Imaging (MRI):
Why: In cases where CT and LP are inconclusive, MRI can provide more detailed images, particularly with FLAIR and gradient-echo sequences.
What to look for: Blood breakdown products and evidence of a small or chronic bleed.
Management: A Step-by-Step Approach
Immediate Resuscitation:
Airway, Breathing, Circulation (ABC): Ensure the patient has a patent airway, is breathing adequately, and has stable circulation.
Blood Pressure Control: Aim to keep systolic blood pressure below 160 mmHg to reduce the risk of rebleeding. Use intravenous antihypertensive like labetalol or nicardipine if necessary.
Pain Management:
Analgesia: Administer appropriate analgesia, such as paracetamol or opioids, to control the severe headache. Avoid NSAIDs due to the risk of bleeding.
Neurosurgical Referral:
Urgent Referral: If SAH is confirmed, an urgent neurosurgical referral is necessary for further management, which may include endovascular coiling or surgical clipping of an aneurysm.
Preventing Complications:
Nimodipine: Administer nimodipine to reduce the risk of vasospasm, a common and serious complication of SAH.
Hydration: Ensure adequate intravenous fluid administration to maintain euvolemia and reduce the risk of vasospasm.
Monitoring and Supportive Care:
Intensive Care: Patients with SAH should be monitored in a high-dependency or intensive care unit for at least 24-48 hours.
Seizure Prophylaxis: Consider anticonvulsants if the patient has had a seizure or if there's a significant risk.
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