Changes in donor care doubles number of lungs for transplants

Some simple changes in how patients who have been declared brain-dead are cared for prior to organ donation could double the number of lungs available for transplant, researchers say.

TORONTO — Some simple changes in how patients who have been declared brain-dead are cared for prior to organ donation could double the number of lungs available for transplant, researchers say.

Altering settings on the ventilator that artificially breathes for the patient can help prevent injury to delicate lung tissue and keep the organs viable for transplantation, said Dr. Arthur Slutsky, an intensive care unit specialist at St. Michael’s Hospital in Toronto.

In a study conducted at 12 centres in Italy and Spain, researchers compared two different artificial breathing strategies in 118 patients whose organs were to be donated.

Half were put on a ventilator using conventional settings, while the other half had “protective” settings that lowered air flow and decreased pressure on exhalation.

In the first group of 59, the lungs of 16 donors could be used for transplantation; in the protective group, the lungs of 32 patients were healthy enough to be transplanted.

“The idea behind this was that many patients are waiting on the list for lung transplants, and unfortunately there’s a shortage of lungs available for transplantation, much more of a shortage than for kidneys and other organs,” Slutsky said.

Lungs deteriorate more quickly than other donor organs, making them unsuitable for transplant, he said, noting that about 15 per cent of patients needing new lungs die on the waiting list.

“So it’s a real shame because transplants can really dramatically change their lives … increase quality of life.”

Slutsky, whose research focuses on mechanical ventilation, collaborated with European colleagues on the study, providing data analysis and co-writing the paper published in this week’s Journal of the American Medical Association.

When a person suffers severe brain injury from which they will not recover, the lungs become more susceptible to injury, explained Slutsky.

“And one of the injuries they’re susceptible to is damage due to the ventilation strategy — that is when you put a tube down and you put a patient on a ventilator, you can actually cause injury.”

“So the idea here was since we have lungs that are more susceptible to injury, we have to treat them very gently as we ventilate the patient.”

Recipients of the lungs, most of whom needed transplants due to chronic obstructive pulmonary disease or pulmonary hypertension, received the same post-operative treatment and their recovery outcomes were similar.

“But there were just twice as many people who got transplants that wouldn’t have got transplants otherwise,” said Slutsky.

The idea of changing ventilator settings isn’t new and ICU doctors at some Canadian hospitals may already be using similar strategies to protect the lungs of organ donors, he said.

“But one of the potentials of this paper is that now that there’s been a formal study done, perhaps people will look at that and say maybe that should be the standard.”

In an accompanying editorial, Dr. Mark Roberts of the School of Public Health at the University of Pittsburgh writes that the study breaks new ground, with results that have “the potential to help eliminate the disparity between demand and supply,” at least for lung transplants.

“The study … provides sobering evidence that conventional lung preservation practices, which have been used for many years, are remarkably inefficient in their task and that improved lung preservation strategies can markedly increase the proportion of donated lungs that are transplanted.”