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May 25, 2000 (San Diego) -- By the time they get to Memphis, the patients are hurting -- and they are angry that neither doctors nor psychiatrists can stop the chronic vomiting that wracks their bodies and lives. They're ready to try anything -- even the biofeedback techniques developed by NASA to help astronauts deal with space sickness -- and that's why they come from all over the U.S. to the autogenic feedback training lab at the University of Tennessee.
Eight weeks later, the vast majority of these patients are feeling much better. "The beauty of this technique is that it is completely safe, with no medications involved," Thomas Abell, MD, tells WebMD. "It can easily be used by pregnant women with severe morning sickness."
Most of the men and women who come to Abell, and colleague Hani M. Rashed, MD, have a much more severe problem than that experienced during early pregnancy. In a presentation to researchers here at the Digestive Disease Week 2000 conference, they said most of the 77 patients they have treated with biofeedback suffer from cycles of vomiting, a disorder of frequent bouts of extremely severe vomiting, often accompanied by migraine headaches and excruciating abdominal pain. These patients usually have failed multiple drug regimens.
"These patients are very sick," Rashed tells WebMD. "Regular tests can't identify this group. But we managed to diagnose patients -- between attacks." The diagnosis is important because the patients seem perfectly normal between attacks. Abell remembers one case in which a teen's parents had to videotape a severe vomiting episode before school officials would believe she wasn't faking her illness.
Rashed and Abell found that while normal people maintain fairly constant heart rate and skin temperature, the patients who had long-standing problems with vomiting do not. This suggests to them that their autonomic nervous system -- the part of the brain that makes the body do all the many things it needs to do without conscious thinking, such as maintaining heart rate and temperature -- somehow fails to do its job properly.
This system is affected in normal people when they go into outer space. The lack of gravity throws their nervous systems out of whack, and their normal body functions become highly erratic. The result is space sickness -- which is such a serious problem for space flight, Abell says, that NASA spent $20 million developing biofeedback techniques so that astronauts could learn how to control body functions that usually remain unconscious.
"When we heard about these techniques in space, we thought maybe this can work back on Earth," says Abell, who is currently with the University of Arkansas in Little Rock. He and Rashed learned the techniques from NASA and adapted them to fit the needs of their patients. They soon uncovered a happy irony: An erratic autonomic nervous system is easier to learn to control than a normal one.
Each biofeedback session lasts 42 minutes, during which the patient sits in front of a screen that displays his or her heartbeat and skin temperature. The session is divided into five cycles of three minutes of relaxation (using standard relaxation techniques as recommended by a consulting psychologist) followed by three minutes of "stimulation." Rashed says, "For three minutes, we have patients think of something that aggravates them, that makes them angry or excited."
Instead of simply trying to lower their heart rate and skin temperature, the patients try to keep them in the normal range -- both when relaxed and aggravated. In between sessions they practice for at least 10 minutes per day.
The result -- in eight out of 10 patients -- is a significant reduction in vomiting and abdominal pain. Soon, Rashed says, patients may not have to go all the way to Memphis for treatment. "Our aim is to develop something that can be applied anywhere," he says. "We are now trying to set up a way to do things by computer over the Internet."