Classification and causes of coma
| Structural brain injury |
| Cerebral hemisphere |
| Unilateral (with displacement) |
| Intraparenchymal haematoma |
| Middle cerebral artery ischaemic stroke |
| Intracranial venous thrombosis |
| Haemorrhagic contusion |
| Cerebral abscess |
| Brain tumour |
| Subdural or extradural haematoma |
| Bilateral |
| Subarachnoid haemorrhage |
| Multiple traumatic brain contusions |
| Penetrating traumatic brain injury |
| Anoxic–ischaemic encephalopathy |
| Multiple cerebral infarcts |
| Bilateral thalamic infarcts |
| Lymphoma |
| Encephalitis |
| Gliomatosis |
| Acute disseminated encephalomyelitis |
| Cerebral oedema |
| Multiple brain metastases |
| Acute hydrocephalus |
| Acute leukoencephalopathy |
| Posterior reversible encephalopathy syndrome |
| Air or fat embolism |
| Brainstem |
| Pontine haemorrhage |
| Basilar artery occlusion and brainstem infarct |
| Central pontine myelinolysis |
| Brainstem haemorrhagic contusion |
| Cerebellum (with displacement of brainstem) |
| Cerebellar infarct |
| Cerebellar haematoma |
| Cerebellar abscess |
| Cerebellar glioma |
| Acute metabolic–endocrine derangement |
| Hypoglycaemia |
| Hyperglycaemia (non-ketotic hyperosmolar) |
| Hyponatraemia |
| Hypernatraemia |
| Addison’s disease |
| Hypercalcaemia |
| Acute hypothyroidism |
| Acute panhypopituitarism |
| Acute uraemia |
| Hyperbilirubinaemia |
| Hypercapnia |
| Diffuse physiological brain dysfunction |
| Generalised tonic–clonic seizures |
| Poisoning, illicit drug use |
| Hypothermia |
| Gas inhalation |
| Acute (lethal) catatonia |
| Malignant neuroleptic syndrome |
| Psychogenic unresponsiveness |
| Hysterical coma |
| Malingering |
Reprinted with permission from Wijdicks EFM. Catastrophic neurologic disorders in the emergency department. Oxford: Oxford University Press, 2004.