Test | Indication | Scope |
---|---|---|
Neurological examination, temperature, pulse, BP, EKG, RR, SpO2 | All patients | Â |
Blood | Â | Â |
Blood glucose | All patients | Rule out hypoglycemia |
Electrolytes | All patients | Rule out severe hypo- or hypernatremia |
Blood gas analysis | All patients | Rule out hypercapnia |
Blood cultures | On clinical suspicion | Rule out systemic infection |
Toxicology screening (from blood and urine) | On clinical suspicion | Rule out intoxications |
Ammonemia and liver function | On clinical suspicion | Rule out hepatic encephalopathy |
Cortisol | On clinical suspicion | Rule out adrenal insufficiency |
Thyroid function | On clinical suspicion | Rule out hypothyroidism |
CSF: routine cell count, protein, Glucose, Gram staining, India ink stain; cultures, including tuberculosis and fungal agents; cytology. HSV and VZV PCR; other agents depending on presentation | On clinical suspicion | Rule out CNS infections, neuroinflammatory diseases or cancer and leukemia dissemination |
Non-contrast CT | All patients | Diagnosis of neurosurgical emergencies and massive stroke |
CTA | On clinical suspicion | Rule out basilar artery occlusion |
MRI | On clinical suspicion | Indicated in case of brainstem symptoms, unexplained coma, or suspected encephalitis |
EEG | On clinical suspicion | Rule out nonconvulsive status epilepticus; may identify electrical patterns typical in some etiologies (e.g., triphasic waves in metabolic encephalopathy) |