β2-Adrenoreceptor Agonist Inhalation During Ex Vivo Lung Perfusion Attenuates Lung Injury.

Background: Attenuation of ischemia reperfusion injury (IRI) is important in lung transplantation. Our group previously reported that β2-adrenoreceptor agonist inhalation during the period before procurement successfully attenuated IRI in donated lungs after cardiac death. We therefore hypothesized that β2-adrenoreceptor agonist inhalation during ex vivo lung perfusion (EVLP) after procurement might also have a protective effect.

Methods: Cardiac-dead beagles were left at room temperature for 210 minutes, and all lungs were subsequently procured and subjected to EVLP for 240 minutes. The beagles were allocated to 2 groups: the β2 group (receiving an aerosolized β2-adrenoreceptor agonist 20 minutes after initiation of EVLP; n = 7) and the control group (receiving an aerosolized control solvent at the same time point; n = 6). Physiologic data, including lung function, were evaluated during EVLP.

Results: The β2 group showed significantly lower peak airway pressure and pulmonary artery pressure than the control group. Dynamic pulmonary compliance was higher, pulmonary vascular resistance (PVR) was lower, and the wet-to-dry lung weight ratio was lower in the β2 group than in the control group. Cyclic adenosine monophosphate (cAMP) and total adenosine nucleotide (TAN) levels in lung tissue after EVLP were higher in the β2 group than in the control group. The β2 group also showed more cystic fibrosis transmembrane conductance regulator (CFTR) gene expression.

Conclusions: After procurement, β2-adrenoreceptor agonist inhalation during EVLP attenuates lung injury in a canine model of organ donation after cardiac death.