MARY LOUISE KELLY, HOST:
For decades, scientists have been trying to create artificial blood for first aid after accidents or in war. Well, those efforts have failed so far, but scientists are now optimistic they may be inching closer to success. A warning, this story lasts about five minutes and includes descriptions and sounds of research on animals. Here's NPR health correspondent Rob Stein.
ROB STEIN, BYLINE: It's early on a Wednesday morning at the University of Maryland School of Medicine in Baltimore. Dr. Allan Doctor hands me something that looks like a surgeon's gown.
ALLAN DOCTOR: This is a lab coat and a mask before we can go into the rabbit room.
STEIN: Oh, OK. Sure thing.
(SOUNDBITE OF DOOR OPENING)
STEIN: The rabbit room is where Doctor's team has been testing their artificial blood. Doctor says extensive animal tests are conducted before the blood can be tried in humans.
DOCTOR: So this is a special intensive care unit that we've created for our rabbit resuscitation.
STEIN: Inside, three big, fluffy white rabbits huddle in metal cages. Doctor's team just drained half the blood from one of them to simulate what happens to someone who's hemorrhaging at a car crash or on the battlefield.
DOCTOR: This rabbit is still in shock. You can see he's lying very still. It's as if he was at the scene of an accident.
STEIN: But they're going to save this rabbit today. They're going to fill its veins with their artificial blood.
(SOUNDBITE OF RABBIT CAGE UNLATCHING)
DANIELLE WATERS: Good bunny.
STEIN: A technician, Danielle Waters, gently lifts out the rabbit...
(SOUNDBITE OF MEDICAL EQUIPMENT PACKAGES BEING OPENED)
STEIN: ...So she can infuse him with three big syringes of artificial blood.
(SOUNDBITE OF MEDICAL EQUIPMENT RUNNING)
WATERS: Here we go.
STEIN: Allan Doctor's team makes this synthetic blood from the protein that nourishes the body with oxygen, called hemoglobin. They extract hemoglobin from expired blood and slip it inside a fat bubble to create artificial red blood cells. That's the new trick that Doctor thinks will solve the safety problems caused by earlier synthetic blood.
DOCTOR: We have to veil the hemoglobin inside a cell. It's an artificial cell. It makes it safe and effective.
STEIN: They then freeze-dry the artificial red blood cells into a powder that stays good until it's needed.
DOCTOR: It's designed so that at the moment it's needed, a medic can mix it with water and within a minute, you have blood.
STEIN: Right now, ambulances and military medics can't routinely carry blood because it would go bad too fast. So tens of thousands of people bleed to death each year in the United States before they can get to a hospital.
DOCTOR: It is shelf stable for years, and it can be easily transported. And so the point is so you can give a transfusion at the scene of an accident.
STEIN: Or on a battlefield. The Defense Department is spending more than $58 million to develop Doctor's artificial red blood cells, along with components needed for clotting and blood pressure.
DOCTOR: We've been able to successfully recapitulate all the functions of blood that are important for a resuscitation in a system that can be stored for years at ambient temperature and be used at the scene of an accident.
STEIN: That's this artificial blood.
DOCTOR: That's right. That's the artificial blood we have here.
(SOUNDBITE OF MEDICAL EQUIPMENT RUNNING)
WATERS: You're being such a good bunny.
(SOUNDBITE OF LONG BEEP)
STEIN: After about 10 minutes, Waters is done infusing the rabbit...
WATERS: Oh, my goodness, Bunny. You did it.
(SOUNDBITE OF RABBIT CAGE OPENING)
STEIN: ...And gently places him back into his cage. The rabbit's vitals immediately shoot back from near death to nearly normal. He's starting to move around again, drink water.
DOCTOR: His eyes are pink. His ears are pink. You know, that's a good sign. He's got a lot of oxygen in his blood, and it's being effectively distributed. And he's breathing comfortably and calm.
STEIN: Yes. His little nose is twitching and paws are moving around. Yeah. He's scrambling around in the cage there now.
(SOUNDBITE OF RABBIT CAGE LATCHING)
DOCTOR: Yeah. It's amazing how quickly it can work.
STEIN: Doctor's team has tested their artificial blood on hundreds of rabbits, making them optimistic.
DOCTOR: It would change the way that we can take care of people who are bleeding outside of hospitals. It'd be transformative.
STEIN: Other experts say, well, lots of promising artificial blood turned out to be dangerous. Tim Estep is a scientist who consults on blood substitute development.
TIM ESTEP: I think it's a reasonable approach, but because this field has been so challenging, the proof will be in the clinical trials. And so although I'm overall optimistic, placing a bet on any one particular technology right now is difficult.
STEIN: Doctor, who cofounded a company to develop his artificial blood, knows he still has to prove to the Food and Drug Administration that it would be safe and effective for people, but he hopes to start human testing within two years. A Japanese team is already testing a similar artificial blood in people.
Rob Stein, NPR News, Baltimore.
(SOUNDBITE OF RODRIGO Y GABRIELA'S "THE SOUNDMAKER") Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.
