Ex-PALM: a negative pressure ventilation system for air leak evaluation in ex vivo lungs

Introduction Prolonged air leaks (PAL) are considered to be one of the leading causes of postoperative complications following lung surgery. There are currently no clinically relevant methods for efficiently and systematically evaluating the underlying causes of PAL. Here, we introduce a new intuitive, physiologically-representative system for ex vivo negative pressure ventilation of lungs, equipped with PAL-oriented features. Methods Reproducibility and system capabilities were assessed using a lung simulation model capable of controlling the effective area of the defect, then validated with ex vivo specimens. Results Our system enables dynamic control of ventilation using either pressure (PCV) or volume (VCV) targets, with respective standard deviations of ±0.08 cm H2O and ±2.1 mL with moderate air leaks (1,000 mL/min). Additionally, leak quantification features proved comparable to that of the Thopaz+ (Medela Healthcare, Baar, Switzerland), a standard commercial digital thoracic drainage system, offering sufficient resolution to differentiate among clinically relevant air leaks. In the lower leak ranges (