Doctors say a Connecticut woman mauled by a 200-pound chimpanzee is making slight progress after more than seven hours of surgery by four teams of surgeons.

Dr. Kevin Miller of Stamford Hospital says 55-year-old Charla Nash suffered extensive facial and hand injuries when she was attacked Monday. He says stabilizing her condition took more than seven hours of surgery.

Nash was attended by hand specialists, plastic surgeons and specialists in orthopedics, ophthalmology and trauma.

Miller says it’s good that Nash has made some progress, but she has a long way to go.

As authorities considered criminal charges against the woman whose 200-pound domesticated chimpanzee mauled Nash, she backtracked Wednesday on whether she gave the animal the anti-anxiety drug Xanax.

Sandra Herold told The Associated Press on Wednesday that she never gave the drug to her 14-year-old chimp, Travis, who was shot dead by Stamford police Monday after he grievously wounded Nash.

However, Herold said in an interview aired Wednesday morning on NBC television that she gave Travis the drug in some tea less than five minutes before he attacked Nash — she even showed a reporter the mug. Police have said Herold told them that she gave Travis Xanax that had not been prescribed for him earlier on Monday to calm him because he was agitated.

In humans, Xanax can lead to aggression in people who are unstable to begin with, said Dr. Emil Coccaro, chief of psychiatry at the University of Chicago Medical Center.

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"Xanax could have made him worse," if human studies are any indication, Coccaro said.

The chimpanzee's rampage forced Herold to stab her beloved pet with a butcher knife and pound him with a shovel. Herold's voice was filled with fear and horror in emergency hot line tapes released by police Tuesday night.

Travis can be heard grunting as she cries for help: "He's killing my friend!"

The dispatcher says, "Who's killing your friend?"

Herold replies, "My chimpanzee! He ripped her apart! Shoot him, shoot him!"

Click to listen to the 911 call.

After police arrived, one officer radioed back: "There's a man down. He doesn't look good," he says, referring to the disfigured Nash. "We've got to get this guy out of here. He's got no face."

Doctors at Stamford Hospital said Wednesday that it took four teams of surgeons more than seven hours to stabilize Nash, 55. Hand specialists, plastic surgeons and specialists in orthopedics, ophthalmology and trauma have treated Nash, who has made slight progress but remained in critical condition, Dr. Kevin Miller said.

Police have said they are looking into the possibility of criminal charges. A pet owner can be held criminally responsible if he or she knew or should have known that an animal was a danger to others.

Attorney General Richard Blumenthal said Wednesday that a defect in Connecticut's laws allowed Herold to keep the chimp in her home, probably illegally. There are rules requiring large primates to be registered by the state, but officials have some discretion in enforcing them and violations carry only minor penalties, he said.

Herold, a 70-year-old widow whose daughter was killed in a car accident several years ago, told the AP the chimp "was my life" and that she "never, never, never" gave it Xanax. "He never had anything but love."

Herold speculated that Travis was being protective of her when he attacked Nash, who she said was driving a different car, wearing a new hairstyle and holding an Elmo stuffed toy in front of her face as a present to the chimp.

"She had the toy in front of her. This was just a freak thing," Herold said.

Authorities are trying to determine why the chimp, a veteran of TV commercials who could dress himself, drink wine from a glass and use the toilet, suddenly attacked. A test for rabies was negative, Stamford police Capt. Richard Conklin said Wednesday.

Travis appeared in TV commercials for Old Navy and Coca-Cola when he was younger, and at home he was treated like a member of the family. Don Mecca, a family friend, said Herold fed the chimp steak, lobster, ice cream and Italian food.

Primate experts say chimpanzees are unpredictable and dangerous even after living among humans for years, but in her NBC interview, Herold rejected criticism that they are inappropriate pets.

"It's a horrible thing, but I'm not a horrible person and he's not a horrible chimp." she said.

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