At an emergency relief air-lift centre at Lafayette Airport, Tony Cramer throws his hands in the air in exasperation.
"We've just delivered three helicopters of water and equipment to those co-ordinates because we were told there were 5,000 people in desperate need.
Caring for the sick and injured is exhausting work
"Now I have some major on the phone who says they've been evacuated in a boat - well that must be a helluva big boat."
For Mr Cramer, flight co-ordinator at Acadian Ambulance Service's air operations base, the misunderstanding is the latest hiccup in a very long day.
All around him swarm Acadian medics and nurses, flight crew, soldiers and volunteers from other states, all desperate to make a difference.
Few have slept more than the odd few hours in the last week while they shuttle back and forth between their base and the worst affected areas of New Orleans.
Mr Cramer returns to the phone to try to get to the bottom of what went wrong. Fellow flight paramedic Scott Saunier is philosophical.
"Let's hope what we have sent does some good somewhere," he says.
Then he is busy again, taking another phone call and preparing the next helicopter flight for take-off, making another contribution to the massive relief effort finally moving into gear.
At the service's offices a couple of miles away, medical director Dr Ross Judice is briefing on what medications are needed on the next emergency flight.
In the bustling operations room, surrounded by large screens with maps of Louisiana and records of response calls, there is an air of determination and efficiency amid ringing phones and the shouts across the room.
Ambulances heading into New Orelans
Three days ago Dr Judice was in the New Orleans Superdome, fighting to treat an ever-growing list of patients amid horrifically unhygienic conditions.
"We were delivering babies in the dark, with nothing more than a flashlight," he said. "People with chronic illnesses needed treatment, but they did not know the names of their medications.
"We were treating lacerations that were getting infected, people were dying of heart attacks - all the while working in such an unsanitary place.
"The circumstances were terrible enough, but it was just as terrible to hear people's stories.
"Loved ones lost in the mayhem, sons who had saved their mothers' lives - I think that will be hardest for me to deal with in the long run."
Acadian is a private company, one of the biggest first responders in the area affected by Katrina and its aftermath.
But the company pulled staff out of the Superdome because of safety concerns after doctors were mobbed by agitated survivors.
Preparing the temporary hospital
Paramedic Jonathan Battin told how he had to abort a mission to save babies from an orphanage after shots were fired near rescue boats.
Some are still angry that more was not done in the first few days after the natural disaster to prevent the spiral into chaos, only now diminishing with the presence of thousands more soldiers.
"Communication has been the big issue all along, says Acadian spokesman Keith Simon.
"We have been trying to do our job the best we can, but until now no one has been taking the lead in co-ordinating our efforts with the security we need."