Facts don’t add up in ‘Seven’
“Seven Pounds”
Columbia Pictures, released Dec. 19
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The premise
Tim Thomas (Will Smith) was the careless driver in a fatal car accident that led to the death of his fiancee and six others. Now extremely depressed and masquerading as his brother Ben, he plans to end his life and donate his organs (7 pounds’ worth) and his home to seven worthy recipients. He gives his bone marrow, a kidney, a lobe of his liver and a lobe of his lung while still alive. He intends to donate his eyes to a blind pianist and his heart to a woman with congenital heart disease. But while waiting for the woman, Emily, to become sick enough to require a heart transplant, he gets to know her and falls in love. She eventually is moved up on the organ-transplant waiting list, but Tim is told that because of her rare blood type, she has only a 3% to 5% chance of receiving a compatible heart. Tim’s blood type is compatible, and he conceives a plan in which he would die while in ice, thus preserving his heart.
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The medical questions
Do the organs and tissue donated amount to 7 pounds? Would an ethics board at a hospital allow someone to donate multiple organs while alive? Could a smoker be saved from lung cancer with a transplant? Are bone marrow transplants so easily done or are they carefully screened for compatibility? Could Tim’s eyes (corneas) be donated to a person of his choice? What are the chances of his heart being compatible with someone with a rare blood type?
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The reality
The organs transplanted don’t quite add up to 7 pounds. “A lobe of the liver is about 2 pounds, but the kidney and a lobe of the lung are only a quarter-pound each, and the heart is only a pound,” says Dr. Lloyd Ratner, director of renal and pancreatic transplantation at Columbia University College of Physicians and Surgeons. Most living donors don’t donate more than one organ, in part because of the physical toll on the body, he says. Further, all donors are screened for depression, and no ethics board at a hospital would allow a person in Tim’s mental state to donate any organ, much less more than one.
Lung cancer: About 1,000 people in the U.S. receive a lung transplant every year (25% of those who are waiting for a lung). But lung transplantation is generally not recommended as a treatment for lung cancer, according to the American College of Chest Physicians. The chance of recurrence or metastasis is high in these patients. Further, “one needs two donors donating one lobe each for living donor lung transplantation,” says Dr. Selim Arcasoy, medical director of the lung transplantation program at Columbia University College of Physicians and Surgeons.
Designating donors: Whether before or after death, liver, kidney and lung donation can all be directed to someone the donor knows. With the heart, this can occur after death. But “a person doesn’t decide to donate his/her marrow to a designated person,” says Susan Stewart, executive director of the Blood & Marrow Transplant Information Network. “The chances of matching someone you specifically choose are minuscule.” In the real world, potential bone marrow donors are HLA (human leukocyte antigen) typed by DNA analysis before being entered into a national registry. When a patient needs a marrow donor, a doctor searches the registry to see whether anyone matches the patient. Searches are conducted anonymously, and donors and recipients don’t know each other.
In addition to HLA typing, potential donors are screened for exposure to infectious diseases, as well as health issues -- including depression -- that would make donating marrow risky for the donor.
Corneas: The cornea is the only tissue in the body that can be transplanted without blood type matching. Corneas are harvested from the newly deceased, as the movie shows, but though it is possible medically for a donor to choose his or her recipient as with other organs, this is not generally done for corneas.
“The overriding factors in determining the recipient are the ages of the donor and recipient, and the quality of the corneal tissue,” says Dr. Anthony J. Aldave, director of the Cornea Service at the Jules Stein Eye Institute at UCLA.
Blood type: The idea of a rare blood type limiting the potential for heart transplant is plausible. In real life, only the four major blood types are screened for compatibility, and according to Ratner, overall there is a 65% chance of compatibility. But the chances of the rarest AB blood type is only 3% to 5%, as the movie depicts, and according to Arcasoy, with heart and lungs, doctors always stick to exact donor matches and do not use universal donors (type O).
Finally, the possibility that someone could die in a bath of ice and still have a donatable heart is also ridiculous, Ratner says, as surgeons look for a donor with a still beating or just-stopped heart.
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Siegel is an internist and an associate professor of medicine at New York University’s School of Medicine. marc@doctorsiegel.com.