When should I consider referring a patient with suspected HACE or HAPE to secondary care?

The provided UK guidelines do not specifically address referral criteria for high-altitude cerebral edema (HACE) or high-altitude pulmonary edema (HAPE) ¹,². However, if a patient with suspected HACE presents with severe neurological symptoms, referral to secondary care would be considered based on criteria for other acute neurological conditions ¹,². For instance, immediate referral to an emergency department for further assessment is indicated for people with suspected subarachnoid haemorrhage who present with unexplained acute severe headache, especially a 'thunderclap' headache, or new symptoms of altered brain function such as reduced consciousness, seizure, or focal neurological deficit, along with nausea and vomiting ¹. Similarly, referral to a hospital emergency department is advised for patients with a head injury who exhibit a Glasgow Coma Scale (GCS) score of less than 15, any loss of consciousness, any focal neurological deficit, a persistent headache, any vomiting episodes, or any seizure since the injury ². The provided guidelines do not contain specific information regarding referral for high-altitude pulmonary edema (HAPE) ¹,².