When disaster strikes, the most vulnerable are always the very old and the very small.
At the Ochsner Clinic in New Orleans, the doctors and nurses of the neo-natal intensive care unit have been working around the clock since Sunday to keep their tiny wards alive.
It was too risky to evacuate the newborns before the storm hit, so as Hurricane Katrina raged outside, the staff calmly went about caring for older patients and babies that, in some cases, were only days old.
They were forced to move the neo-natal unit from the top-floor to a lower one, but in general, the building they're in has stood up to the elements. They are 8 feet above sea level, but there has been some flooding inside.
But these newborn babies are the most fragile of beings -- completely dependent on technology that is, in turn, completely dependent on electricity.
One 3-week-old named Hayden is alive only because he's hooked up to a heart-lung machine. But if the hospital loses power, and the batteries on Hayden's heart-lung machine run down, there would only be one option left: creating electricity manually, via a hand crank.
The situation is very similar to the aftermath of last December's tsunami in Asia, said Dr. Rachel Moresky, an emergency physician at the Columbia University medical center, who was there as part of the international relief effort.
Moresky said after the initial danger from injuries and infections, the next immediate risk for natural disaster survivors is usually disease. Luckily, in the case of the tsunami, the fears of cholera and other outbreaks did not materialize.
Katrina has also given rise to fears that alligators and poisonous snakes have been flushed from the swamps, but wildlife experts say they probably won't pose a major risk. However, they warn that rabies is always a concern when wild animals and humans are forced together by circumstance.
By late Wednesday, most hospitals in the hurricane-ravaged region were evacuating their patients to hospitals as far away as Houston.
Ochsner officials said they are not planning to evacuate the entire hospital. Out of their 580 beds, they have approximately 300 left, and they plan to evacuate 150 of them.
Those left will be the most at-risk patients, which includes Hayden. The doctors and nurses of the neo-natal intensive care unit are managing to hold out. Their generators are still running, and they are able to power everything but the air conditioners.
However, morale is high. Through all the devastation, one nurse managed to make a joke. "It's extremely hot and we're all uncomfortable," she said, "but they let us dress like we want."
Ironically, while the heat is causing so much misery for the hospital workers, is a blessing in disguise for the babies. The nurses usually have to worry about the babies getting cold.
Under constant care, 3-week-old Hayden is doing fine. The maintenance staff erected a temporary tent above his bed to shelter him from leaks that sprung up during the storm.
Before Katrina slammed into New Orleans, Hayden's parents had to be convinced to leave.
Family members were encouraged to evacuate because the doctors and nurses of the Ochsner clinic have enough on their hands with caring for the patients, and caring for each other.
The 500 men and women of Ochsner clinic may not be hanging from helicopters and rescuing people from rooftops, but there are plenty of people who still consider them heroes: for risking their own lives by braving the hurricane and the flood and the heat.