Rep. Gabrielle Giffords no longer needs a respirator after doctors replaced the breathing tube for a tracheotomy tube.

Giffords had surgery Saturday morning to have a tube inserted into her windpipe to protect her airway. She has been breathing on her own since last Saturday, when she was shot in the head, but doctors kept the breathing tube in and connected to a ventilator as a precaution.

The procedures are common for brain-injured patients.

Giffords remains in critical condition and her husband, astronaut Mark Kelly, remains by her bedside. However, doctors have been quite optimistic about her pulling through.

Meanwhile, the Tucson, Arizona Safeway store where the shooting rampage took place last Saturday reopened. While some came to shop, many came to the site to pay their respects to the six who were killed when a gunman opened fire during Giffords' "Congress on Your Corner" event.

"Our employees have been through so much but they are here, they're working and kind of anxious to reconnect with their customers and the community. We're doing OK," store spokesperson Cathy Kloos told The Associated Press.

Employees at the store observed a minute of silence in a memorial for the victims.

A gun show in Tucson was also being held Saturday, despite the tragedy.

Six people were killed, and 13 were injured in last week's attacks.

Accused gunman Jared Loughner has been charged with the attempted assassination of a member of Congress; two counts of killing an employee of the federal government; and two counts of attempting to kill a federal employee.

More charges are expected.