HOUSTON - She rode to the airport in an ambulance Friday, an Arizona flag-embossed helmet protecting her exposed brain. But that didn't stop wounded Rep. Gabrielle Giffords from recognizing the applause from constituents on the Tucson streets.

The Arizona congresswoman smiled, according to those riding with her, and then appeared to tear up, causing an emotional moment for her husband, mother and doctors on their way to a Houston rehabilitation center.

The rest of the trip from Tucson - a two-hour flight, followed by a quick helicopter ride to the Texas Medical Center - went just as well, according to one of the passengers, Randall S. Friese, associate medical director at Tucson's University Medical Center. The transfer went "flawlessly," he said at a crowded news conference after Giffords checked into the intensive care unit at Memorial Hermann Hospital.

"She looked spectacular in all ways. Neurologically, she was alert, awake, calm and looked comfortable," added Dong Kim, director of the neuroscience department at Memorial Hermann.

Giffords will remain in intensive care until doctors are sure that they have relieved fluid in her brain that caused swelling several days ago. That swelling led doctors, shortly after she was hospitalized in Tucson, to remove a portion of her skull to ease the cranial pressure. They said they will replace that piece of skull once they see no more threat of swelling - a process that could take several weeks.

Even so, doctors stressed that they expected her to begin physical therapy Friday afternoon. Eventually, she will be transferred to the nearby TIRR Memorial Hermann rehabilitation center, where a treatment plan is being discussed.

Friese said of the applause Giffords received on her way out of Arizona: "It was very heart-wrenching, so wonderful to see the support from Tucsonans. We're going to miss her while she's here. But this is the place she should be."

Giffords (D-Ariz.) was shot above the left eye during the Jan. 8 shooting rampage in Tucson that killed six and injured 13. Kim said the congresswoman has good movement on the left side of her body and "good tone in her leg, which is a precursor to a more full recovery." Her right leg, however, is in worse condition and might not be able to support her body weight, he said. Her arms also have less movement.

Overall, Giffords "has great rehab potential. She will keep us busy and we will keep her busy," said Gerard Francisco, the rehabilitation center's chief medical officer.

While Giffords was traveling to Houston, the Pima County sheriff's deputies who responded to the scene of the shooting recounted for the first time the frantic moments upon their arrival. They described a scene of "silent chaos" and said the carnage likely would have been much worse without the help of a $99 first-aid kit that recently became standard-issue.

It was devised by David Kleinman, a Pima County SWAT team medic, who cobbled together the "First Five Minutes" kit out of simple tools used by combat medics in Iraq and Afghanistan: an emergency bandage pioneered by the Israeli army, a strip of gauze that coagulates blood on contact, a soft tourniquet and other inexpensive materials.

It is unusual for police officers to carry such medical equipment, but the gear proved crucial, officials said. "It would have been a lot worse" without those tools, said Sheriff's Department Capt. Byron Gwaltney.

In Houston, Giffords will get a standard room - a hospital bed, a bathroom - in a relatively private wing of the rehabilitation center.

"It's very spartan," Francisco said. "We don't plan to treat her any differently than we treat someone with a similar injury. It's business as usual. It's the rehabilitation program that we would provide anyone with this type of impairment."

TIRR is a highly renowned rehabilitation center, ranked fifth in the nation last year by U.S. News & World Report. Its 200 staffers treat 119 inpatients and handle 46,000 outpatient visits each year, according to information provided by the hospital.

Giffords's husband, Mark Kelly, an astronaut who trains at Houston's Johnson Space Center, said the family chose TIRR over facilities in Washington, New York and Chicago in part because of its proximity to his work and family. Carl Josehart, TIRR's chief executive, said families are encouraged to participate actively in the recovery process because they will be expected to provide care at home once the patient is released.

Like her fellow patients, Giffords will spend the better part of her days working out in one of the rehabilitation center's half-dozen gymnasiums. Each is equipped with what Francisco fondly referred to as his "toys" - a bevy of high-tech exercise equipment, muscle stimulators and robotic devices designed to help patients regain muscle control, coordination and cognition.

There is a therapeutic pool, which includes a hydraulic lift to help injured patients into the water and a body-weight treadmill, on which patients are strapped to a harness that supports them while they walk (hospital staffers also provide assistance). There are special recumbent stationary bikes that pulse electrodes into patients to stimulate muscles. And there is a tilting table, to which patients who have trouble standing are strapped so they can slowly be adjusted into a standing position.

In addition to physical therapy, staff members will help Giffords with speech and language, her cognitive ability and the skills needed to perform daily activities such as brushing her teeth and getting dressed, Francisco said.

The facility has a special kitchen and a washer and dryer - spaces and equipment where patients can practice basic household chores that help assess their readiness to reenter ordinary life.

Francisco acknowledged that there is no guarantee that Giffords, or any patient who has suffered a severe brain injury, will return to full health.

"It's a function of what part of brain is damaged and the extent of the injury," he said. "Some with brain injury like this lose the ability to speak, lose the ability to understand. Their personality changes, they have problems with memory. It changes how they relate to people."

Giffords is already showing signs of relating to people. During the trip, she grabbed a ring from the hand of Tucson nurse Tracy Culbert, who has attended her since the shooting and accompanied her on the plane. Culbert put the ring on Giffords's finger. When Friese later tried to take the ring back from Giffords, the congresswoman tried not to let it go, the doctor said.

Recounting the tale, Culbert said: "Do you want me to cry? It's very emotional. She's a very gentle person and her personality is coming out. The way that she touches us. The way that she looks at us. I'm very lucky to know her."

nakamurad@washpost.com sandhya@washpost.com Somashekhar reported from Tucson. Staff writer Sari Horwitz contributed to this report from Tucson.