How should I manage a patient with a recent history of headache and sudden onset neck stiffness in the context of potential subarachnoid haemorrhage?

Initial assessment and suspicion: In a patient presenting with recent headache and sudden-onset neck stiffness, maintain a high index of suspicion for subarachnoid haemorrhage (SAH), especially if the headache was sudden and severe (thunderclap headache) peaking within 1 to 5 minutes. Neck stiffness is a recognized symptom of SAH and should not be overlooked ¹.

Immediate action: Refer the patient immediately to an emergency department for urgent assessment and investigation, as SAH is a medical emergency requiring prompt diagnosis and treatment ¹.

Diagnostic investigations: The patient should undergo an urgent non-contrast CT head scan, ideally within 6 hours of symptom onset, as this has the highest diagnostic accuracy for detecting SAH ¹.

If CT is positive: Diagnosis of SAH is confirmed if blood is seen in the subarachnoid space on CT. The patient should then be discussed urgently with a specialist neurosurgical centre for further management ¹.

If CT is negative and within 6 hours: Routine lumbar puncture is not required. Consider alternative diagnoses but discuss with a senior clinical decision-maker and seek specialist advice ¹.

If CT is negative and more than 6 hours have passed: Perform a lumbar puncture at least 12 hours after symptom onset to detect xanthochromia, which confirms SAH if present ¹.

Symptom management: Provide effective pain relief, including opioid analgesia if necessary, and document its use as it may affect neurological assessment ¹.

Further imaging: If SAH is confirmed, CT angiography should be performed without delay to identify the source of bleeding and guide treatment ¹.