Tuesday, March 11, 2014
By MICHAEL E. RUANE The Washington Post
(Continued from page 1)
Army Sgt. Brendan Marrocco, 26, of Staten Island, N.Y., wears a prosthetic arm at an event at the 9/11 Memorial in New York last July 4. He is the first soldier from the wars in Iraq and Afghanistan to survive losing all four limbs.
The Associated Press
Donor and recipient do not necessarily have to be of the same gender, but the limbs should match in size, skin color, and tissue and blood type. About two years ago, he said, at a California hospital, a female recipient successfully received a transplanted hand from a male donor.
Time is critical.
In a double transplant, all four arms must be carefully readied, with the skin peeled back and the bone ends often cut at angle, as a good carpenter might, for a solid connection, according to a textbook on transplantation Lee and his colleagues are writing.
Inside the arm, individual muscle-tendon units, nerves and blood vessels are identified. They are then tagged with pieces of light blue sterile bandages that are sewn in place and labeled in permanent black marker to ensure proper connection.
The connecting sequence begins with the bones, which are joined with metal plates. "It's not as easy as fixing a fracture," Lee said, "because the two ends of the bone belong to different people."
Next, he said, "we typically connect the muscles and tendons."
After that, "we put together the blood vessels," he said. "That's the critical part, where we need to restore circulation to the transplanted limb by connecting the arteries and the veins. And they're typically done under a microscope."
Finally, the skin is sewn together.
Lee said war injuries have often resulted in amputations higher up the arm.
That is more problematic, in part, because nerves in the donor arm are dead and must be replaced by the recipient's nerves, which regenerate down the arm at a rate of about an inch a month.
Rejection, and especially the drugs used to combat it, pose other problems.
"We want the best of both worlds," Lee said. "We want to do the transplant, improve the quality of life, but not incur the side effects of the traditional anti-rejection regimen."
Experimenting in the laboratory with pigs, he said, the team discovered that infusions of bone marrow cells from the donor can reduce the amount of anti-rejection drugs required.
He said experts must use care in approaching donors' families about arm transplants.
"We typically relay through (the organ-procurement organization) the story of the recipient," he said. "For that reason, I think, we were very rarely turned down by the grieving family," he said.