It usually doesn’t take a doctor for one to tell if someone is in coma or not because the signs of unconsciousness and unresponsiveness are quite clear and therefore, it can be said that coma is a straightforward diagnosis. But, when it comes to diagnosing the prospective causes of coma, the task becomes a bit more difficult and requires the attention of a trained medical professional.
If coma or persistent vegetative state results from a traumatic injury to the head, the cause is clear. But, if a second party calls the hospital for help, it may be difficult to judge what really caused the coma, especially if it happened because of reasons other than an obvious injury to the head. Observers or those people who called for help can tell the doctor about medical details of the patient i.e. if they are close enough to know. These details may include information about what medications the patient too, what symptoms were observed immediately before the patient went into coma and how quickly the patient lost consciousness. The doctor may also want to know about the medical history of the patients because certain disorders are likely to trigger coma and these disorders include diabetes, heart, lung, liver, kidney or disease of another crucial organ and seizure disorder.
A physical examination of the patient may be done if not much information can be gathered from. For instance, sometimes, an overdose of a narcotic can cause very small pupils that do not respond to bright light. Certain specific tests may be done to diagnose the condition accurately.
Specific tests that may be used to diagnose coma include the following:
• Urine and blood tests to check for any disease, toxins or metabolic disorders
• Electroencephalogram, a graph of the electrical output of the brain that may indicate a metabolic imbalance of persistent seizure activity inside the brain. If there is an absence of electrical activity on repeated EEGs and not much can be found on the reversible cause front, the patient is said to be brain dead and treating him/her is considered to be futile.
• Computed tomography or magnetic resonance imaging scans to look for bleeding in the brain, infection, tumor or stroke from a lack of or decreased blood flow.
• Lumbar puncture to examine the cerebrospinal fluid for possible signs of meningitis and encephalitis.
Read more articles on Coma and Persistent Vegetative State.