Caution urged after study on brain activity by 'vegetative' patients

By Nancy Frazier O'Brien
Catholic News Service

WASHINGTON (CNS) – New evidence of brain activity in patients judged to be in a persistent vegetative state should make physicians and neurologists more cautious in arriving at such judgments in the future, according to a Catholic ethicist.

Edward Furton, a staff ethicist and director of publications at the National Catholic Bioethics Center in Philadelphia, told Catholic News Service March 1 that recent research shows doctors sometimes "underestimate the consciousness of patients," who can be "more aware than they are given credit for."

In a study published in February in the New England Journal of Medicine, researchers in England and Belgium found that five of 54 patients in states of persistent unconsciousness showed distinct patterns of brain activity on a brain imaging machine in response to questions that required a "yes" or "no" answer.

Four of the responsive patients studied had been diagnosed as being in a persistent vegetative state, while the fifth had been considered minimally conscious. The other 49 patients in the study showed no signs of conscious brain activity.

"These results show a small proportion of patients in a vegetative or minimally conscious state have brain activation reflecting some awareness and cognition," the study concluded. "Careful clinical examination will result in reclassification of the state of consciousness in some of these patients."

The researchers said the technique used in the study "may be useful in establishing basic communication with patients who appear to be unresponsive."

The technique involved magnetic resonance imaging of the brains of patients who were asked to think about tasks associated with either the motor or spatial parts of the brain. Thinking about playing tennis, for example, would stimulate the motor imagery section of the brain, while imagining walking around a house would stimulate the spatial imagery section.

Patients then were asked to associate "yes" with "tennis" and "no" with "house" in responding to a series of questions requiring "yes" or "no" answers. The five patients previously considered unresponsive were able to respond correctly to each of the questions.

"Such a capacity, which suggests at least partial awareness, distinguishes minimally conscious patients from those in a vegetative state and therefore has implications for subsequent care and rehabilitation, as well as for legal and ethical decision making," the study's authors said.

Some say patients in a persistent vegetative state have no meaningful brain activity or chance of recovery; that argument led a Florida judge to order the removal of a feeding tube for Terri Schiavo, leading to her death in March 2005. Schiavo's parents and siblings had fought her estranged husband to keep her on the feeding tube.

Terri Schiavo's brother, Bobby Schindler, said the latest New England Journal of Medicine study "underscores ... why this dangerous and often mistaken PVS diagnosis needs to be stopped when being used as a standard to kill our most vulnerable."

Schindler said in a Feb. 23 statement that people "with cognitive disabilities thought to be in this PVS condition, like Terri, are routinely being denied food and hydration – their most basic rights."

Furton said the misperceptions about the awareness of those in persistent vegetative states is similar to scientists' earlier beliefs about fetal pain. Some contended that a fetus could not feel pain until shortly before birth, "but that has been shown to be false," he said.

"There has been a tendency to underestimate" the awareness and pain levels of those "at the beginning of life and at the end of life," he said.

"If there is any doubt" about whether a person diagnosed as being in a persistent vegetative state is consciously aware, "you have to err on the side of caution," Furton added.