Cerebral hyperperfusion syndrome (CHS) – unlikely to see it in ED, but worth knowing about if you work in a hospital where you are part of the medical emergency team

– occurs after carotid endarterectomy or carotid angioplasty in up to 3% of patients

– characterised by throbbing ipsilateral frontotemporal or periorbital headache, vomiting, confusion, visual disturbances (secondary to macular oedema), hypertension, seizures, and focal neurological deficits; if not treated properly it can result in severe brain oedema, intracerebral or subarachnoid haemorrhage and death

Risk factors:

– increases of more than 100% in perfusion compared with baseline after carotid endarterectomy

– previous cerebral infarction, especially in the first 3 – 4 weeks

– diabetes mellitus; longstanding hypertension

– age > 72 years