Ex vivo Lung Perfusion: A Technique for Pulmonary Research in a Rabbit Model

An ex vivo lung perfusion system allows the recreation of blood circulation and ventilation in isolated human and animal lungs to assess their function. Begin with isolated rabbit lungs with an attached heart on sterile gauze. Insert a tracheal cannula and ventilate the lungs via positive pressure for continuous lung activity.

Cut off the heart ventricles and insert cannulae into the pulmonary artery and the left atrium. Secure the cannulae with the neighboring tissues to avoid distention during perfusion. Inject isotonic saline through the arterial cannulae to flush out residual blood. Assemble the isolated lungs into a lung chamber by attaching the tracheal cannula to the ventilation system and the arterial cannulae to the perfusion system. Both systems are connected to a data acquisition system that measures different physiological parameters.

Now, switch the ventilation from positive to negative pressure to ensure optimal oxygenation and perfusion in the lungs. Then, slowly perfuse the lungs with artificial perfusate and gradually step up to a maximum flow rate. Modify the arterial and venous pressure to achieve zone three ventilation, a physiological state when both the arterial and venous pressures are higher than the alveolar pressure, causing maximum pulmonary vessels to open. This allows the proper distribution of perfusate into the pulmonary capillaries.

Collect real-time data for the desired parameters to evaluate lung function.