Laboratory tests are more helpful in the diagnosis of patients with disorders of consciousness or coma, and routine tests should be done first, followed by blood chemistry and other special tests if necessary. For patients with unknown causes, urine routine should be checked, and for those suspected of central nervous system pathology, cerebrospinal fluid examination should be done. Urine routine examination: 1. urine sugar and ketone body: can diagnose except diabetic acidosis and hyperosmolar non-ketotic coma (except for those with high renal threshold), hypoglycemic coma, starvation ketosis, lactic acidosis, diabetes combined with other causes of coma, hyperosmolar non-ketotic diabetic coma, diabetic ketoacidosis. 2, urine protein: a large amount and accompanied by red and white blood cells, tubular type, should be considered the possibility of uremic toxicity. 3, urine bile: urine bilirubin positive, urine bilirubin greater than 1:20, suggesting liver damage. Blood tests: 1. Leukocytes: All patients with sluggish reflex to light should have a leukocyte count, and those with increased leukocytes should consider infection, inflammation, dehydration and other stressful conditions. Decreased white blood cells, to suspect blood disease or hypersplenism. 2.Hemoglobin: Anyone suspected of internal bleeding and anemia should have their hemoglobin checked. 3, platelets: those with bleeding tendency, platelet count should be checked. Those with low platelet count should consider the possibility of blood disorders. 4, other: suspected of carbon monoxide poisoning, should be carbon monoxide qualitative test. Cerebrospinal fluid examination: 1. If the cerebrospinal fluid pressure is increased in patients with retarded reflex to light, it indicates increased intracranial pressure. 2. Routine and biochemical (protein, sugar, chloride) examinations: bloody cerebrospinal fluid under the naked eye or microscope should be considered as intracranial hemorrhage if puncture trauma can be excluded. Normal cerebrospinal fluid examination with clinical hemiplegia should be considered ischemic cerebrovascular disease. High cerebrospinal fluid pressure with normal routine and biochemistry may be toxic or metabolic encephalopathy. Increased white blood cells in the cerebrospinal fluid are indicative of infection or inflammatory disorders. A normal cerebrospinal fluid cell count with increased protein may be an intracranial tumor, demyelinating disease, or infectious polyneuritis. 3, other tests: consistent with the performance of the cerebrospinal fluid of septic meningitis, Gram smear should be made to find bacteria and culture, and drug sensitivity determination. If it is consistent with tuberculous meningitis, film smear should be done to find tuberculosis bacteria. For fungal meningitis, centrifugal sedimentation and ink smear should be used to find fungi. Cerebrospinal fluid can also be used for a variety of serum immunological tests, such as immunoglobulin, syphilis reaction, and oligoclonal bands. Cytological examination is also available.