ATLANTA, Georgia (AP) -- At Atlanta's main trauma hospital, lines of waiting patients clog the hallways -- even on slow days.Doctors say they probably couldn't handle a major plane crash or any other incident with more than 20 or 30 severe injuries."It's a struggle to meet the nightly demand of 911 calls," said Dr. Arthur Kellermann, an ER physician at the hospital, Grady Memorial."But somehow we're supposed to deal with a ... terrorist bombing? Or a new strain of influenza?"Trauma centers and emergency departments similarly are strained in many U.S. cities, experts say."Trauma systems are never more than a couple of minor incidents from being overwhelmed," said Larry Gage, president of the National Association of Public Hospitals and Health Systems.Hurricane Katrina destroyed New Orleans' only trauma center. A few years ago, funding problems nearly closed primary trauma centers in Detroit and Los Angeles, and more than a dozen other U.S. hospitals have phased-down or shuttered their trauma units since.That trend, along with a growing U.S. population, is making it harder for many hospitals to quickly and adequately handle severe emergencies."Across the country, the level of crowding at emergency departments has reached levels that are unprecedented in America's history," said Dr. Kathleen Clem, chief of emergency medicine at Duke University Medical Center.Trauma and emergency care is a money loser, serving many patients without health insurance. It's also expensive to maintain a round-the-clock staff of specialized surgeons and trauma-care medical workers.In Atlanta, hospitals often pay subspecialists around $1,000 per day to take calls for trauma care.For those reasons, many hospitals have gotten out of trauma care, increasing the load on those that have stayed in that business, industry experts say.Grady Memorial is Atlanta's primary emergency care center, with about 200,000 visits a year, and it's been getting busier.Patient volumes have been increasing more than 5 percent a year at the 953-bed hospital, driven by a variety of factors including an expanding city population and the closing of trauma centers near Atlanta.As at other hospitals, Grady's 100 intensive care unit beds are often completely filled, meaning dozens of gurneyed patients at a time have to wait in the ER for a bed to open upstairs. That, along with a heavy flow of new cases, doesn't allow much room for dealing with a multi-trauma incident.Grady is expecting a loss of between $9 million and $10 million this year, and would need more government funding to expand its ICU and emergency capabilities, said Dr. Leon Haley Jr., the hospital's chief of emergency medicine.In New Orleans, the situation is unusual in that hurricane flooding -- not scarce funding -- closed the main trauma center. But some ER doctors say that, even before the floods, they expected problems getting the center reaccredited this fall.Charity Hospital, once one of the nation's largest hospitals, was home to New Orleans' only top-level trauma center, with staffing and equipment to handle the most complex emergency injuries. The hospital was getting 160,000 emergency and trauma visits a year.But 650-bed Charity was irreparably damaged by floodwaters after Hurricane Katrina. Since then, most of the city's trauma and emergency cases have been handled in U.S. Navy ships, temporary combat hospital tents, and in four civilian hospitals that have managed to restore at least some of their services.But the ships left weeks ago. And the combat hospital tents, which are currently the city's main trauma center, are scheduled to pack up later this month."It's going to be a major problem," said Helen Ruiz, director of the emergency department at Touro Infirmary, the only downtown hospital ER currently open.Charity's parent organization, the Louisiana State University Health Care Services Division, is trying to lease a hospital and re-establish a trauma center. But it's also struggling to cover bills."We are a bus crash away from complete and total disaster," said Donald Smithburg, chief executive of the LSU hospital organization.But the story is different in Detroit. Officials at Detroit Receiving Hospital, the Motor City's long-standing chief trauma center, said their center is on solid footing right now and has been able to handle multiple-trauma incidents pretty well.But it's a turnaround, they say, from the situation two years ago, when budget shortfalls spurred rumors that the trauma center would have to close. An infusion of state money saved the day, said Dr. James Tyburski, the hospital's chief of surgery.In September, emergency physicians from across the country gathered in Washington to rally for additional government support. More than 3,000 physicians attended and spoke in favor of a measure that would increase Medicare payments to emergency doctors and hospitals by 10 percent.But the bill so far has only two sponsors. Emergency physicians say they are amazed that the Bush administration is willing to spend billions to stockpile Tamiflu for a possible super-flu outbreak -- even though it's not clear the medicine would be effective -- while showing disinterest in aiding emergency hospitals that would have to handle flu cases.Emergency departments are the perfect cauldrons for a dangerous strain of flu to spread through large numbers of immune-compromised people, said Kellermann, the Grady physician. Emergency centers should be expanded to have respiratory isolation areas and other services, he argued."We're worried about a flu pandemic and we're parking patients cheek to cheek," he said. "That's just mind-bogglingly stupid."Copyright 2005 The Associated Press. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed.