Hospitals across the city faced deteriorating conditions Tuesday after two levees broke, sending water coursing through the streets of the Big Easy. An estimated 80 percent of the below-sea-level city was under water, up to 20 feet deep in places, with miles and miles of homes swamped.

As floodwaters rose around Charity Hospital, the rescuers needed their own rescuing.

Charity's backup generator was running out of diesel fuel. Nurses hand-pumped ventilators for patients who couldn't breathe. Doctors canoed supplies in from three nearby hospitals.

"It's like being in a Third World country. We're trying to work without power. Everyone knows we're all in this together. We're just trying to stay alive," said Mitch Handrich, a registered nurse manager at the state's biggest public hospital.

U.S. Health and Human Services Secretary Mike Leavitt (search) said 2,500 patients would be evacuated from hospitals in Orleans Parish, but it wasn't immediately clear where they would be moved.

Police were working to get more generators to Charity and its 300 patients. The most critically ill would be evacuated first, with the rest to go later this week.

Outside Charity, water was 3 to 4 feet deep in the street. Inside, halls were dark and slippery. Workers ferried supplies up and down darkened stairs. Everyone needed flashlights.

And yet the injured kept coming. At one point, a boat pulled up carrying a man doubled over in pain.

"Where are we going to put him? We're the rescuee now. People coming in here, it's like running into a burning building looking for shelter," nursing supervisor Ray Campo said.

Helicopters landed at the hospital's parking garage — sometimes first picking up specialists from other cities — to get about 25 sick babies and take them to hospitals in Lafayette, New Iberia and Alexandria, said Richard Zeuschlag, president of Acadian Ambulance Service Inc.

Boats had to take other patients eight miles to a highway intersection, where 80 ambulances waited to ferry them for triage at the LSU Assembly Center in Baton Rouge.

Other hospitals were also scrambling to get patients out.

Tenet Healthcare Corp. said it was evacuating its 317-bed Memorial Medical Center and 187-bed Lindy Boggs Medical Center in New Orleans. The company's 203-bed Kenner Regional Medical Center in Kenner, 207-bed Meadowcrest Hospital in Gretna, and 174-bed NorthShore Regional Medical Center in Slidell remained open with back-up power but also suffered water and wind damage.

Most hospitals had supplies and generator power for three to five days, but the effects of Hurricane Katrina (search) would last much longer. "They're short of supplies and diesel, and without people to get to them," Zeuschlag said.

Medical disaster teams, able to triage and treat as many as 250 patients in three days were on their way from seven states to areas damaged by the storm, the Federal Emergency Management Administration (search) said. Two veterinary teams were also coming to handle pets and rescue dogs.

Perched a lofty 8 feet above sea level in Jefferson Parish, Ochsner Clinic was one of the few in the area still up and running. It tried to focus on taking in only those patients with life-threatening illnesses.

On Tuesday, that included two near-fatal electrocutions of people who tried to return to flooded areas, and others who were injured by flying glass when wind and water smashed their shelters.

Even at the clinic, broken glass littered some areas, and patients and staff alike had fallen on floors slick with hurricane waters. With electricity and air conditioning out, generators were providing the only power.

But there was ample water, food, blood and medical supplies to do everything needed, and enough power to keep medical machinery humming, hospital officials said, crediting the plans and preparations made before the storm hit.

"I'm proud to tell you that, things are going — under the circumstances — really well," said nurse Jackie Lupo, director of labor and delivery.

Several women gave birth during the ordeal, each baby announced with a tune over the loudspeaker.

"Nobody named one Katrina yet," said clinic spokeswoman Katherine Voss.