New Technique Expands Donor Pool

Photo: Human bowels between stomach and throat

The patient who received the
repaired lung was able to breathe
without assistance four days
after the surgery; © SXC

In their research, a team of lung transplant surgeons led by Shaf Keshavjee developed an “ex vivo” or outside the body technique capable of continuously perfusing or pumping a bloodless solution containing oxygen, proteins and nutrients into injured donor lungs. This technique, allows the surgeons the opportunity to assess and treat injured donor lungs, while they are outside the body, to make them suitable for transplantation.

Unlike current cooling lung preservation techniques which inhibit cell metabolism and the possibility of any active repair processes prior to transplantation, the Toronto technique maintains donor lungs at a normal body temperature of 37 degrees Celsius, allowing for future organ repair and gene and cell therapy strategies to be used on them. Although lung perfusion systems have been used in Sweden and England, these systems were blood-based, short-term assessment strategies which were not capable of long-term maintenance or techniques to repair or recondition the lungs.

The Toronto System was used on donor lungs for Andy Dykstra, 56, who received his transplant on December 5, 2008. He had been waiting for a transplant since July 30, 2008. Andy is part of an ongoing clinical trial which uses the novel Toronto strategy to identify donor lungs which do not meet current transplant criteria, repair them, and then transplant them into patients. Andy was the first patient who received lungs which did not meet standard transplant criteria and which could not have been used if they had not been repaired first by the Toronto System.

“We are extremely pleased that Andy is doing so well,” said Keshavjee, adding that Andy was able to breathe without any mechanical assistance just four days after the transplant and was discharged from hospital twelve days after the procedure. “It means that many more donor lungs which we could not have used before can now potentially be used safely, and it sets the stage for more sophisticated molecular and cellular repair techniques to be applied in the Toronto System so that transplant outcomes can be further improved. The potential exists to immunologically pre-prepare the organ before it even sees the recipient’s immune system.”; Source: University Health Network (UHN)