(A coma is a state of unconsciousness where a person is unresponsive and cannot be woken.)
Coma is a loss of consciousness involving unawareness of self, others, the external world, and the passage of time. The individual in a coma is unable to respond to external events or basic needs such as eating or drinking.
Head trauma, drug use, epilepsy, and brain infections are the most common causes of coma in individuals less than 40 years of age. Cardiovascular disease ( Specially stroke) and metabolic disorders ( Diabetes mellitus, hypoglycemia, coma from liver failure, electrolyte disorders, and uremia are common causes in those over 40 years.
Causes of Coma:
Many types of problems can cause coma. Some examples are:
• Traumatic brain injuries. Traumatic brain injuries, often caused by traffic collisions or acts of violence, are common causes of comas.
• Stroke. Reduced or interrupted blood supply to the brain (stroke), which may be caused by blocked arteries or a burst blood vessel, can result in a coma.
• Tumors. Tumors in the brain or brainstem can cause a coma.
• Diabetes. In people with diabetes, blood sugar levels that become too high (hyperglycemia) or too low (hypoglycemia) can cause a coma.
• Lack of oxygen. People who have been rescued from drowning or those who have been resuscitated after a heart attack may not awaken due to lack of oxygen to the brain.
• Infections. Infections such as encephalitis and meningitis cause swelling (inflammation) of the brain, spinal cord or the tissues that surround the brain. Severe cases of these infections can result in brain damage or a coma.
• Seizures. Ongoing seizures may lead to a coma.
• Toxins. Exposure to toxins, such as carbon monoxide or lead, can cause brain damage and a coma.
• Drugs and alcohol. Overdosing on drugs or alcohol can result in a coma.