Ex Vivo Lung Perfusion in the Rat: Detailed Procedure and Videos

Ex vivo lung perfusion (EVLP) is a promising procedure for evaluation, reconditioning, and treatment of marginal lungs before transplantation. Small animal models can contribute to improve clinical development of this technique and represent a substantial platform for bio-molecular investigations. However, to accomplish this purpose, EVLP models must sustain a prolonged reperfusion without pharmacological interventions. Currently available protocols only partly satisfy this need. The aim of the present research was accomplishment and optimization of a reproducible model for a protracted rat EVLP in the absence of anti-inflammatory treatment. A 180 min, uninjured and untreated perfusion was achieved through a stepwise implementation of the protocol. Flow rate, temperature, and tidal volume were gradually increased during the initial reperfusion phase to reduce hemodynamic and oxidative stress. Low flow rate combined with open atrium and protective ventilation strategy were applied to prevent lung damage. The videos enclosed show management of the most critical technical steps. The stability and reproducibility of the present procedure were confirmed by lung function evaluation and edema assessment. The meticulous description of the protocol provided in this paper can enable other laboratories to reproduce it effortlessly, supporting research in the EVLP field.