It's a sight that warms the scroogiest of hearts: Droves of people making their way to their local blood donation centers following a large-scale tragedy or natural disaster. The aftermath of the Las Vegas mass shooting last Sunday has proven to be no exception. Across the city, The New York Times reported Monday, people were standing in lines that spanned the block, eager to honor the memory of the 58 people killed by the gunman's high-powered weaponry and to help the more than 500 hundred people injured.
But well-intended as these efforts are, blood centers and doctors are left once again lamenting an unfortunate reality: A sizable portion of this blood is likely to get thrown out.
"There's always a need for more blood during these tragedies, but what often happens is that the outpouring of donations is way over that need," explains David Andrews, a pathologist at the University of Miami School of Medicine in Florida. Andrews also runs the blood lab and oversees the blood bank at the university's hospital as well as at the privately-owned Jackson Memorial Hospital.
The problem is two-fold, Andrews says. For one, the infrastructure surrounding blood donation is a delicate balancing act. It usually takes at least three or four days before freshly donated blood can clear safety tests, be processed, and be made available to doctors like Andrews. So any blood that's used in the wake of a major tragedy is usually blood obtained before it even happened.
"It's the blood on the shelf" that matters most during a tragedy, Louis Katz, Chief Medical Officer of America's Blood Centers, the country's largest network of community blood centers, tells Tonic. "If there's an event now, and you come to the blood center even two hours later, the people who are going to die of bleeding are already dead by the time it's ready."
And while these events can drain the available amount of blood that centers can later supply hospitals with, the limitations of blood storage itself further muck up how useful an immediate donation can be. The individual components of blood spoil at different speeds, but donated platelets become unusable after a mere five days; red blood cells last around 42 days.
So when even blood suppliers like the Red Cross are graciously inundated with scores of new donors, if it isn't used rather quickly, much of the blood will go in the trash. And it's not just a matter of supply and demand, either. Andrews notes that natural disasters can continue to wreak havoc on the local blood supply after they're over—for instance, by making it impossible for trucks carrying donations to reach afflicted areas.
All of this means that it's often better to wait in the wings rather than rush right out to your next blood drive. "The most important thing about the blood supply is it's like a pipeline. It's not a bank," Dr. Leslie Greebon, a fellow blood lab director at the University Hospital in Texas, told KENS-5. In Texas as well as Florida—states recently hit by massive hurricanes in the past month—the most urgent need for blood came weeks after the disaster had long passed through.
"I understand [the desire to immediately donate]. It's absolutely a visceral response. 'What can I do? I can donate blood!' I get it," says Katz, who recalls spending time after 9/11 gently convincing people in line to donate to wait a while longer. Infamously, nearly half of the 500,000 added donations made following the terrorist attacks were ultimately discarded, a fact that unfortunately scared donors away once it was made public.
The absolute best thing to do then, experts everywhere agree, is to open up a regular account at your nearest blood bank. "Everything about regular donors is good for the system, as opposed to people who just show up once and then go away," Andrews says.
"People who don't always donate need to call their local center and find out what their needs are," Katz says. "Because we try to anticipate five, ten days down the line what we need as well and we need to stage donations to meet that need as people are recovering."
As for what people in Las Vegas and elsewhere need right this moment?
"Right now, the Red Cross is encouraging eligible individuals to make an appointment to give in the coming weeks to help ensure a sufficient blood supply moving forward," the Red Cross said in a statement to Tonic. "Accident and burn victims, heart surgery and organ transplant patients, and those receiving treatment for leukemia, cancer or sickle cell disease all count on blood donations to battle illness and injury."
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