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Pulmonary air leak is the most common complication of lung surgery, with air leaks that persist longer than 5 days representing a major source of post-surgery morbidity. Clinical management of air leaks is challenging due to limited methods to precisely locate and assess leaks. Here, we present a sound-guided methodology that enables rapid quantitative assessment and precise localization of air leaks by analyzing the distinct sounds generated as the air escapes through defective lung tissue. Air leaks often present after lung surgery due to loss of tissue integrity at or near a staple line. Accordingly, we investigated air leak sounds from a focal pleural defect in a rat model and from a staple line failure in a clinically relevant swine model to demonstrate the high sensitivity and translational potential of this approach. In rat and swine models of free-flowing air leak under positive pressure ventilation with intrapleural microphone 1 cm from the lung surface, we identified that: (a) pulmonary air leaks generate sounds that contain distinct harmonic series, (b) acoustic characteristics of air leak sounds can be used to classify leak severity, and (c) precise location of the air leak can be determined with high resolution (within 1 cm) by mapping the sound loudness level across the lung surface. Our findings suggest that sound-guided assessment and localization of pulmonary air leaks could serve as a diagnostic tool to inform air leak detection and treatment strategies during video-assisted thoracoscopic surgery (VATS) or thoracotomy procedures.
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Lung‐Mimetic Hydrofoam Sealant to Treat Pulmonary Air Leak
Abstract Pulmonary air leak is the most common complication of lung surgery, contributing to post‐operative morbidity in up to 60% of patients; yet, there is no reliable treatment. Available surgical sealants do not match the demanding deformation mechanics of lung tissue; and therefore, fail to seal air leak. To address this therapeutic gap, a sealant with structural and mechanical similarity to subpleural lung is designed, developed, and systematically evaluated. This “lung‐mimetic” sealant is a hydrofoam material that has alveolar‐like porous ultrastructure, lung‐like viscoelastic properties (adhesive, compressive, tensile), and lung extracellular matrix‐derived signals (matrikines) to support tissue repair. In biocompatibility testing, the lung‐mimetic sealant shows minimal cytotoxicity and immunogenicity in vitro. Human primary monocytes exposed to sealant matrikines in vitro upregulate key genes (MARCO, PDGFB, VEGF) known to correlate with pleural wound healing and tissue repair in vivo. In rat and swine models of pulmonary air leak, this lung‐mimetic sealant rapidly seals air leak and restores baseline lung mechanics. Altogether, these data indicate that the lung‐mimetic sealant can effectively seal pulmonary air leak and promote a favorable cellular response in vitro.
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- Award ID(s):
- 2143620
- PAR ID:
- 10640933
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 13
- Issue:
- 13
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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