Doctors are following the playbook in treating Buffalo Bills football player Kevin Everett’s severe spinal cord injury except in one notable regard: pumping icy cold saline into his veins to try to prevent further damage.

Although the treatment is experimental, it is more science than science fiction, and also is being tried on stroke and brain injury patients.

“There are compelling reasons why one might want to try it” in a case like this, said Dr. Gary Steinberg, chairman of neurosurgery at Stanford University. He had no role in Everett’s case but has tested the body cooling treatment.

Everett’s prognosis remains uncertain. His doctors were encouraged by signs on Tuesday that he could move his legs and arms — a day after saying he stood little chance of making a full recovery. They also have said that his spinal cord was intact rather than severed — a very good sign.

Doctors say that it is far too soon to know whether he will be left with any paralysis or its extent.

“Walking out of this hospital is not a realistic goal, but walking may be,” Dr. Andrew Cappuccino, the team’s orthopedic surgeon, said at a news conference in Buffalo on Wednesday.

That does not mean a return of his career, though, said Dr. Joseph Maroon, team neurosurgeon for the Pittsburgh Steelers and a University of Pittsburgh specialist who was consulted on Everett’s case.

“If he ever does regain function, no neurosurgeon would ever permit him to play football,” Maroon said.

Everett suffered a fracture and dislocation of his spinal cord in the neck area during a game Sunday night against the Denver Broncos. Watching it on television from home was Dr. W. Dalton Dietrich, scientific director for the Miami Project, a spinal cord program affiliated with the University of Miami Miller School of Medicine.

The program is among several in the United States that has led research into moderate hypothermia, or cooling the body a few degrees to try to limit swelling, inflammation and the cascade of events and chemicals that cause further damage after an initial neurological injury.

Dietrich sent an urgent e-mail to fellow neurosurgeon Dr. Barth Green, who knows Buffalo Bills owner Ralph Wilson.

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Who did what next is unclear, but doctors say Everett received the experimental cooling therapy in the ambulance, even before X-rays and other tests could show the extent of his injury and the treatment he would need.

The goal of the treatment is “to cool the tissue a few degrees to reduce its need for oxygen and to reduce its metabolic rate” and limit secondary damage from chemicals the body releases after the initial injury, said Dr. Elad Levy, a University of Buffalo neurosurgeon who treated Everett.

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On Monday, as Everett’s temperature began to rise, doctors decided to try cooling his body again, using a slightly different system. This time, a hollow tube called a catheter was inserted into the femoral vein in the leg near the groin, and cold saline was circulated through the veins but not put directly into the bloodstream.

“We did this here at the University of Pittsburgh in the 70s,” but with a different method of threading a catheter directly over the spinal cord, Maroon said. The treatment had to be done within three hours of injury to have any benefit and was extremely cumbersome, he said. For that and other reasons, it was largely abandoned until recently, when doctors have resumed testing it through different cooling methods for stroke and brain injury patients.