An experimental study of the recovery of injured porcine lungs with prolonged normothermic cellular exvivo lung perfusion following donation after circulatory death.

Abstract

Donation after circulatory death (DCD) is an underused source of donor lungs. Normothermic cellular exvivo lung perfusion (EVLP) is effective in preserving standard donor lungs but may also be useful in the preservation and assessment of DCD lungs. Using a model of DCD and prolonged EVLP, the effects of donor warm ischemia and postmortem ventilation on graft recovery were evaluated. Adult male swine underwent general anesthesia and heparinization. In the control group (n=4), cardioplegic arrest was induced and the lungs were procured immediately. In the four treatment groups, a period of agonal hypoxia was followed by either 1h of warm ischemia with (n=4) or without (n=4) ventilation or 2h of warm ischemia with (n=4) or without (n=4) ventilation. All lungs were studied on an EVLP platform for 24h. Hemodynamic measures, compliance, and oxygenation on EVLP were worse in all DCD lungs compared with controls. Hemodynamics and compliance normalized in all lungs after 24h of EVLP, but DCD lungs demonstrated impaired oxygenation. Normothermic cellular EVLP is effective in preserving and monitoring of DCD lungs. Early donor postmortem ventilation and timely procurement lead to improved graft function.