Sarah Murnaghan's aunt speaks to media after her niece receives an adult lung for a transplant to combat her cystic fibrosis.

The lungs offered Wednesday to a dying 10-year-old girl whose transplant plight changed the nation’s organ allocation rules came from an adult donor, perhaps proving that her parents were right all along.

Sarah Murnaghan of Newtown Square, Pa., underwent more than six hours of surgery to receive two lobe transplants, meaning that a pair of adult lungs was cut down to fit her small size, according to a statement from her family, including parents Janet and Francis Murnaghan.

"We are thrilled to share that Sarah is out of surgery," the statement read. "Her doctors are very pleased with both her progress during the procedure and her prognosis for recovery."

Murnaghan family. Sarah Murnaghan, 10, who has been waiting for a lung transplant for 18 months, had surgery on Wednesday, her family said.

That indicates that a giant push by Sarah's parents, which resulted in a lawsuit and a federal court order, actually worked as they’d hoped: to allow their daughter to receive adult lungs based on the severity of her illness instead of existing rules.

“It is wonderful that the transplant is proceeding,” said Art Caplan, director of medical ethics at New York University’s Langone Medical Center. “The parents really went the extra mile.”

It wasn’t immediately clear if the lungs came from someone who designated the organs specifically for Sarah or whether she was the sickest recipient included on the adult lung transplant waiting list in her region. The girl, who suffers from end-stage cystic fibrosis, had been waiting on the pediatric lung list since 2011.

The surgeons had no challenges resizing and transplanting the donor lungs, the family said. "The surgery went smoothly and Sarah did extremely well."

As of Wednesday, 217 people were waiting for lungs -- including six children younger than 10 -- in Sarah’s geographical area, Region 2, according to data from the Organ Procurement and Transplantation Network, or OPTN. That includes Washington D.C., Delaware, Maryland, New Jersey, Pennsylvania and West Virginia. Nationwide, nearly 1,700 people are waiting for lungs, including 30 children younger than 10.

Learn more about how to become an organ donor

Officials and doctors at Children’s Hospital of Philadelphia, where Sarah has been in worsening health for three months, refused to comment on her status or to discuss the larger issue of pediatric organ transplants. The family thanked the surgeon who performed the operation, Dr. Thomas Spray, and Sarah's team of doctors and nurses.

The move came days after a federal judge ordered Health and Human Services Secretary Kathleen Sebelius to direct OPTN to place Sarah in line on the adult list, while at the same time maintaining her priority on a pediatric list for children younger than 12.

Under U.S. District Court Judge Michael Baylson's order, OPTN added Sarah on the adult list as of 10:34 p.m. June 5, according to a letter from Sebelius.

The Murnaghan family took pains to thank the organ donor's family.

"We are elated this day has come, but we also know our good news is another family's tragedy," they wrote. "That family made the decision to give Sarah the gift of life -- and they are the true heroes today."

On Monday, the OPTN board of directors voted to allow special consideration for children needing lung transplants. Under the decision, the children’s doctors can classify certain kids under age 12 as adolescents, then petition OPTN to give them access to a larger pool of lungs while ensuring that organs do not go to waste.

Anne Paschke, an OPTN spokeswoman, said the agency could not provide information about any particular patient.

“That said, we certainly wish the best for Sarah and all transplant candidates and recipients,” added Paschke.

A second mother, Milagros Martinez, also filed suit last week on behalf of her 11-year-old son, Javiar Acosta, who also has severe cystic fibrosis and is waiting for a lung transplant. Both families challenged rules that prevented children younger than 12 from being offered adult lungs until after the organs were offered others on the adult list – even if the kids were sicker.

They argued that a 2005 system that revamped the way lungs were allocated for adults and teens may have cut waiting list deaths in that group, but actually penalized children who were younger than 12 but large enough to get adult or teenage-sized lungs.

Critics contended that changing the rules would allow Sarah and others to “jump the line” for organ transplants, bumping other equally deserving recipients. But the parents argued that they weren’t looking for special consideration, just an equal chance at receiving life-saving organs based on the severity of illness.

Experts cautioned that the transplant process is difficult and delicate. Nearly 80 percent of lung transplant patients survive the first year, but only about half survive after five years, according to the National Heart Lung and Blood Institute.

Sarah Murnaghan, the 10-year-old Pennsylvania girl who sparked a national debate about transplant rules about children receiving lungs, will receive a transplant. Dr. Ben Gaston from University Hospital Case Western weighs in on the effects of this case on other kids awaiting transplants.

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