The 8-year-old victim of a shark attack off the Florida coastline is expected to survive, despite extensive surgery and his still-critical condition.

Mississippi resident Jessie Arbogast, who was mauled by a shark in the sea July 6, got his most promising medical report Friday. Doctors at Sacred Heart Children's Hospital said the boy is expected to survive and is no longer in a deep coma.

Jessie, who is still in critical condition, was breathing on his own and responding to pain and discomfort by grimacing, opening his eyes and making slight body movements.

"We are hopeful for a very good recovery," said Dr. Ben Renfroe, a pediatric neurologist who has been caring for the child. "We are very excited about the progress he has made so far."

The biggest concern remains whether the 8-year-old suffered brain damage, though tests showed no evidence of swelling or injury.

The Ocean Springs, Miss., boy was attacked by a bull shark July 6 at the Gulf Islands National Seashore. Jessie lost his right arm, suffered a deep wound to his right leg and lost nearly all his blood, which damaged other organs.

His uncle and a beachgoer hauled the 7-foot shark ashore. The boy's arm was pulled from the animal's gullet, and it was reattached during an 11-hour surgery.

Jessie's recovery is expected to be slow, said Dr. Rex Northup, a pediatric intensive care physician.

"The chance of a sudden, almost instantaneous, awakening from this type of thing is unusual," Northup said.

Doctors said the boy's kidneys were improving. He was taken off dialysis Thursday but did not show as much improvement as doctors had hoped. They planned to put him on a gentler form of dialysis.

Kidney failure actually may be a positive sign for Jessie's brain, Renfroe said. A body reacts to blood loss by shunting remaining blood to the heart and brain.

"That's why the kidneys took such a big hit and the heart did not," Renfroe said. "So we're very hopeful that in actuality he didn't go a long period of time without blood to his brain. It certainly doesn't seem so."

The Associated Press contributed to this report.