brain, spinal cord, and nerve disorders
Stupor and Coma
Symptoms of Stupor and Coma
Consciousness is impaired to varying degrees. People in a stupor are usually unconscious but can be aroused with vigorous stimulation. People in a coma are unconscious, with their eyes closed, and they cannot be aroused. The brain damage or dysfunction that causes stupor and coma affects other parts of the body. Thepattern of breathingis usually abnormal. People may breathe too rapidly, too slowly, too deeply, or irregularly. Or they may alternate between these abnormal patterns. Blood pressuremay increase or decrease, depending on the cause of the impaired consciousness. For example, if a head injury causes massive bleeding in the brain, pressure within the skull rapidly increases, and blood flow to the brain decreases. The nerves that control blood pressure respond by increasing blood pressure to try to maintain normal blood flow to the brain. If the cause of impaired consciousness is a severe infection, severe dehydration, major blood loss, overdoses of certain drugs, or cardiac arrest, blood pressure decreases dramatically. Musclesmay contract and remain contracted in unusual positions. For example, the head may be tilted back with the arms and legs extended—a position called decerebrate rigidity. Or the arms may be flexed with both legs extended—a position called decorticate rigidity. Or the entire body may be limp. Sometimes muscles contract sporadically or involuntarily. Theeyesmay be affected. One or both pupils of the eyes may be widened (dilated) and may not react to changes in light. Or the pupils may be tiny. The eyes may not move or may move in abnormal ways. The disorder that is impairing consciousness may cause other symptoms. For example, if the cause is meningitis (infection of the layers of tissue covering the brain and spinal cord), early symptoms may include fever, vomiting, headache, and a painful, stiff neck that makes lowering the chin to the chest difficult or impossible. Being unable to move (immobilization) for a long time, as occurs in coma, can also cause problems, such as pressure sores, nerve damage in the limbs, blood clots, and urinary tract infections (see Problems Due to Bed Rest ). 