This work provides a foundation for future studies aimed at increasing the understanding of air leaks to better inform means of mitigating the risk of air leaks under clinically relevant conditions.

PurposeThoracic air leaks are a common complication following pulmonary resections. Limitations in clinical studies and preclinical models have hindered efforts to understand the pathophysiology of air leaks. With an emphasis on staple-line specific air leaks, we hypothesize that ventilation modality – intraoperative positive pressure vs postoperative negative pressure – and stapler design may play a role in air leaks.MethodsUsing a novel physiologic lung model, air leaks associated with graduated and uniform staple designs were evaluated under positive and negative pressure ventilation, simulating perioperative breathing in porcine lungs. Air leak incidence, air leak volume, and air leak rate were captured along with ventilation pressure and tidal volume.ResultsIn all cases, negative pressure ventilation was associated with a higher occurrence of leaks when compared to positive pressure ventilation. Lungs leaked more air and at a faster rate under negative pressure ventilation compared to positive pressure ventilation. Graduated staple designs were associated with higher occurrence of leaks as well as larger leak rates when compared to uniform staples. Tissue thickness was not associated with differences in air leaks when tested with appropriate staple heights.ConclusionUsing a novel lung model to investigate the pathophysiology of air leaks, we have identified breathing modality and staple design as two important variables that may impact air leaks. This work will help guide device design and drive future studies in human tissue, and it may help inform clinical practice to ultimately improve patient outcomes.

Background: Staple line reinforcement (SLR) is a popular tool used by surgeons to increase staple line strength and improve peri-operative hemostasis. However, currently marketed buttress materials require special attention in attachment to the staple anvil and cartridge and may come loose during typical maneuvering of stapling procedures. We have evaluated a new SLR that has an attachment material that affixes buttress across the entire anvil and cartridge face to prevent slipping, twisting, sliding and/or bunching. Methods: In benchtop and preclinical testing, the new buttress material (ECHELON ENDOPATH™ Staple Line Reinforcement) was compared to a commercially available SLR for physical characteristics, including strength, absorption, security on the anvil and cartridge during stapler manipulation, impact on the tissue healing response and tissue abrasion. The two SLR's were also compared to a staple line without buttress for hemostasis. Results: The new SLR was 180% stronger initially and maintained a greater strength for up to 14 days of exposure to an in vitro solution (p≤0.001), even though it was lighter and exhibited a faster rate of degradation. The new buttress material maintained complete adherence to the anvil and cartridge throughout tissue manipulation, whereas the commercial product lost substantial coverage in 72% of samples. Both SLR's provided superior hemostasis to the non-buttress control, with minimal impact on tissue healing or abrasion. Conclusion: Because the new buttress material comes with attachment material affixed across the entire anvil and cartridge face of the stapler and maintains coverage during manipulations, it should be much easier to use. The physical characteristics of the new SLR were as good as or better than current product that requires the buttress to be applied to the cartridge and anvil. In addition, the new SLR is similar in hemostasis to standard products and superior to stapling without the use of buttress. Further research is needed to determine whether these preclinical benefits carry over into a clinical setting.