The respiratory system, consisting of the lungs and air passages, provides the body with a continuous supply of oxygen as well as a means of removing carbon dioxide. The life-sustaining oxygen that we inhale 17,000 times a day passes from the lungs to the bloodstream, which then transports it to cells throughout the body.
Respiratory disorders serious enough to cause long-term breathing problems are common in the United States and will increase in prevalence as the Baby Boom population ages. Almost 400,000 Americans die of lung diseases every year, and over 35 million are now living with chronic lung disease.
Fortunately, technological advances are producing opportunities to replace lungs permanently damaged by end-stage diseases such as chronic obstructive pulmonary disease, cystic fibrosis, pulmonary hypertension, or alpha-1 antitrypsin deficiency. As a result, people with these disorders are living longer and better lives today than they just a decade ago.
Since the early 1990s, more than 25,000 lung transplants have been performed at medical centers around the world. In the United States, more than 1,800 lung transplants out of a pool of over 100,000 potential candidates are expected to be completed in 2012. These people had no other medical options and were expected to die from lung disease within one to two years.
While lung transplantation is a lifesaver, donor lung shortage is a major limiting factor to the number of transplants that can be performed annually. Lungs are harvested from only 15 percent of donors due to the lung’s vulnerability to complications that arise before and after donor brain deaths such as pneumonia, thoracic trauma, ventilator associated lung injury, or pulmonary edema.
That is all about to change. Experts believe that as many as 40 percent of previously rejected donor lungs may now be suitable for transplantation thanks to a new approach called ex vivo—outside the body—lung perfusion. This novel “lung washing” procedure can reverse lung injury in many donor organs deemed unsuitable and allow for transplantation.
With scores of successful transplantation cases of ex vivo lungs that have been repaired and regenerated, this is not science fiction. In this new pioneering procedure, the damaged lungs are removed from a donor, placed in a bubble-like transparent chamber, and connected to a cardiopulmonary pump and a ventilator. Over a four- to six-hour period, the lungs are then repaired and assessed. Special proprietary fluids are forced through the blood vessels and nutrients are used to renourish the lungs as they inflate and deflate as oxygen is pumped through. When necessary, targeted medications are introduced to clear infections. Once determined as being viable, they are ready for immediate transplantation.
Ex vivo lung perfusion, which is approved in Europe and Canada, and is now undergoing a major multicenter clinical trial in the United States, has the potential to significantly increase the number available lungs as the reconditioning process is adopted, refined, and improved at multiple transplant centers. This increased availability of quality-tested donor lungs is going to make a huge difference to the 100,000 American patients with severe breathing problems who now wait on the lung transplant standby list.
Where Are They Now
Receiving FDA approval in 2014, this lung preservation and healing technique has allowed hospitals to preform 28% more lung transplants with the same amount of donors, saving countless lives. 2,075 lung transplants were performed in the U.S. in 2015, but more than 200 people died waiting for transplantable lungs. The first lung transplant in Texas using donated lungs treated with the new technology was performed in June 2016. Ex vivo lung perfusion is expected to increase the number of lungs available for transplant by 10 to 15 percent.