Only about 15% of the potential candidates for lung donation are considered suitable for
transplantation. Thus, a strategy that could improve the quality and precision of assessment
of nonacceptable donor lungs could have a major impact on reducing waiting time and mortality
while on the list.
A new method for ex vivo lung perfusion (EVLP) has been developed recently by Steen and
colleagues to assess the quality of lungs from a non-heart-beating donor. The method can also
be used to recondition "marginal" and nonacceptable donor lungs.
After harvesting, the lungs were perfused ex vivo with Steen Solution, an extracellular
matrix with high colloid osmotic pressure. A membrane oxygenator connected to the circuit
received gas from a mixture of nitrogen and carbon dioxide, maintaining a normal mixed venous
blood gas level in the perfusate. The lungs were gradually rewarmed, reperfused, and
ventilated for evaluation through analyses of oxygenation capacity, pulmonary vascular
resistance (PVR), lung compliance (LC), and biopsy.