The legal wrangling is effectively over: Doctors will not reinsert the feeding tube that kept Terri Schiavo alive for 15 years. Within days the brain-damaged 41-year-old Florida woman will die.
What will she go through in her last days? To find out, National Geographic News asked several neurologists for a medical explanation of Schiavo's condition. They all agreed that, assuming that Schiavo is in fact in a persistent vegetative state, she will not experience physical pain.
Persistent Vegetative State
On February 25, 1990, Schiavo suffered severe brain damage when her heart stopped because of a potassium imbalance. Oxygen was cut off from her brain for about five minutes.
Courted-appointed doctors have consistently said that the brain damage from the cardiac arrest left Schiavo in a persistent vegetative state (PVS). She is unable to eat or drink on her own and, without assistance, will die.
James Bernat is a professor of neurology at the Dartmouth Medical School in Hanover, New Hampshire. He said PVS patients suffer damage to the parts of the brain involved in awareness—the cerebral cortex, the thalamus, and the connections between them. The brain stem, which is responsible for basic functions like breathing and wakefulness, continues to operate relatively normally.
"This neuronal damage creates a state in which the patient is awake but unaware. The patient's eyes are open while awake and closed while asleep," Bernat said.
PVS patients lack anything resembling a normal, conscious experience, according to Roger Albin, a professor of neurology at the University of Michigan in Ann Arbor. "A person in that state is completely unaware of anything, including themselves," he said.
Bruce Sigsbee, a neurologist in Rockport, Maine, added that a PVS diagnosis "requires that there is no demonstrated response to any environmental stimulus beyond simple reflexes"—involuntary movements, such as when a doctor bangs on a patient's knee.
Environmental stimuli used to gauge awareness can range from simple to complex. Examples include touching a patient, giving a simple command, applying what should be moderately painful pressure, and waving an object in hopes of stimulating eye movement.
Still Breathing
Schiavo is able to breathe because her brain stem—the lower part of the brain that connects it to the spinal cord—is intact. But without a functioning cerebral cortex and thalamus, she is unable to eat or drink on her own, doctors say.
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