BackgroundControversies surrounding the efficacy of surgical sealants against alveolar air leaks (AAL) in lung surgery abound in the literature. We sought to test the sealing efficacy of a novel synthetic sealant, TissuePatch™ in an in vitro lung model.MethodsThe lower lobe of freshly excised swine lung (n = 10) was intubated and ventilated. A superficial parenchymal defect (40 × 25 mm) was created, followed by AAL assessment. After sealant application, AAL was assessed again until burst failure occurred. The length of defect was recorded to evaluate the elasticity of the sealant.ResultsSuperficial parenchymal defects resulted in AAL increasing disproportionally with ascending maximal inspiratory pressure (Pmax). Multiple linear regression analysis revealed strong correlation between AAL and Pmax, compliance, resistance. After sealant application, AAL was sealed in all ten tests at an inspired tidal volume (TVi) of 400 ml, in nine tests at TVi = 500 ml, in seven at TVi = 600 ml and in five at TVi = 700 ml. The mean burst pressure was 42 ± 9 mBar. Adhesive and cohesive sealant failures were found in six and three tests respectively. The length of defect before sealant failure was 8.9 ± 4.9% larger than that at TVi = 400 ml, demonstrating an adequate elasticity of this sealant film.ConclusionsTissuePatch™ may be a reliable sealant for alternative or adjunctive treatment for repair of superficial parenchymal defects in lung surgery. The clinical benefits of this sealant should be confirmed by prospective, randomised controlled clinical trials.AbstraktHintergrundDie Wirksamkeit von chirurgischen Klebstoffen zur Prävention von alveolo-pleuralem Luftleck (APL) ist trotz zunehmenden klinischen Anwendungen in Lungenchirurgie immer noch kontrovers diskutiert. Wir evaluierten die Abdichtungswirksamkeit von einem neuartigen synthetischen Kleber, TissuePatch™ mittels eines in vitro Lungenmodels.MethodeDer Unterlappen von frisch entnommenen Schweinlungen (n = 10) wurde intubiert und beatmet. Eine pleurale Läsion (40 × 25 mm) wurde erstellt und APL mit steigendem inspiratorischem Tidalvolumen (TVi) untersucht. Nach Applikation von TissuePatch™ wurde APL auf die gleiche Weise gemessen bis zur Auftritt von Kleberbruch. Zur Untersuchung der Elastizität des Klebers wurde die Länge der pleuralen Läsion gemessen.ErgebnisPleurale Läsion führte bei aufsteigendem maximalem inspiratorischem Druck (Pmax) zu überproportionalem Anstieg von APL. Multiple lineare Regressionsanalyse ergab eine starke Korrelation zwischen APL und Pmax, Lungencompliance sowie Widerstand. Nach der Applikation von Klebstoff wurde APL bei TVi = 400 ml in allen zehn Testen versiegelt, bei TVi = 500 ml in neun Testen, bei TVi = 600 ml in sieben und bei TVi = 700 ml in fünf Testen. Der mittlere Pmax, der zu Kleberbruch führte, betrug 42 ± 9 mBar. Bei den Versuchen wurden adhäsiver und kohäsiver Kleberbruch in jeweils sechs und drei Testen gefunden. Die Länge der pleuralen Läsion vor dem Kleberbruch war 8,9 ± 4,9% größer als die bei TVi = 400 ml.SchlussfolgerungUnsere...

BackgroundAlbumin-glutaraldehyde glue gained a widespread acceptance in repair of superficial lung defects associated with alveolar air leaks (AAL). As its sealing efficacy has not yet been thoroughly corroborated by clinical studies, we sought to assess the properties of commercially available albumin-glutaraldehyde glue (BioGlue™) in an in vitro lung model.MethodsThe lower lobe of freshly excised swine lung (n = 10) was intubated and ventilated. A focal superficial parenchymal defect (40 × 25 mm) was created on the inflated lung. AAL was assessed with increasing inspired tidal volume (TVi). After glue application, AAL was assessed until burst failure occurred. To evaluate glue elasticity, the length of defect was recorded in the inflated lung.ResultsSuperficial parenchymal defects resulted in AAL increasing with ascending TVi. Multiple linear regression analysis revealed strong correlation between AAL and maximal inspiratory pressure. There was one application error. At TVi = 400, 500, 600, 700, 800 and 900 ml, BioGlue™ achieved complete sealing in nine, six, five, four two and one specimens, respectively. Mean burst pressure was 38.0 ± 4.2 cmH2O. All sealant failures were cohesive. BioGlue™ allowed an expansion of covered lung defects of 1.5 ± 1.7 mm.ConclusionsOur in vitro tests demonstrated a high sealing efficacy of BioGlue™ for repair of superficial lung defects. Due to the rigid nature, caution should be taken to use this kind of sealant in trapped lungs.

Background Controversies surrounding the efficacy of sealants against alveolar air leak (AAL) are abundant in the literature. We sought to test the widely used sealants, TachoSil (Takeda Pharmaceutical Company Limited, Osaka, Japan) and BioGlue (CryoLife Europa Ltd., Surrey, United Kingdom) in an in vitro model. Materials and Methods After creation of a focal superficial defect (40 Â 25 mm) in swine lungs (n ¼ 40), AAL was assessed with increasing inspired tidal volume (TVi). Upon sealant application in a randomized order, AAL was assessed in the same way until sealant burst. Results At TVi ¼ 400, 500, 600, and 700 mL, BioGlue achieved sealing in 19, 19, 16, and 14 tests, while TachoSil sealed in 19, 14, 4, and no test, respectively. The maximally tolerated pressure of BioGlue was higher than TachoSil (40.3 AE 3.0 vs. 36.0 AE 4.9 cm H 2 O, p ¼ 0.003). Cohesive and adhesive failures were found in 10 and 1 tests of BioGlue, respectively, while all burst failures of TachoSil were adhesive. Concerning elasticity, TachoSil allowed more expansion of the covered defect than BioGlue (6.3 AE 3.9 vs. 1.4 AE 1.0 mm, p < 0.001). Conclusion The tested sealants demonstrated high sealing efficacy. While BioGlue was superior in resisting higher ventilation pressure, TachoSil possessed better elasticity.

BackgroundAlbumin-glutaraldehyde glue has gained widespread acceptance for treatment of alveolar air leaks (AAL) in thoracic surgery. As liquid run-off during application is detrimental to its sealing efficacy, we developed a modified technique and assessed it in vitro.MethodsCaudal lobes of freshly excised swine lungs (n = 20) were intubated and ventilated. A standardized focal superficial parenchymal defect (40 × 25 mm) was created on the inflated lung. AAL was assessed under exposure to increasing inspired tidal volume (TVi). Lung lobes were randomly selected and subjected to either a standard sealing suggested by the manufacturer (control group) or a modified technique relying on placement of a square silicone frame around the lesion site (study group). AAL was subsequently assessed until burst failure occurred and the occuring lesions length was recorded on the inflated lung to evaluate elasticity of underlying tissue.ResultsSuperficial parenchymal defects resulted in AAL increasing with ascending TVi. AAL prior to sealant application was comparable in both groups. An application error occurred once in our control group. At TVi = 400, 500, 600 and 700 ml, the albumin-glutaraldehyde glue achieved complete sealing in 10, 10, 9 and 8 lungs respectively in our study group, as opposed to 9, 7, 6 and 4 lobes in the control group. The required mean burst pressure was significantly higher in our study group (41.0 ± 1.0 vs. 37.5 ± 4.2 cmH2O, p = 0.0195), but there was no difference in expansion of covered defect between both groups (1.0 ± 0.4 vs. 1.5 ± 1.7 mm, p = 0.3772).ConclusionsOur tests suggest that frame-assisted sealant application might prevent glue run-off and thus improves its sealing efficacy. We encourage further investigation of this technique in well-designed, controlled clinical trials.Electronic supplementary materialThe online version of this article (doi:10.1186/s13019-016-0544-6) contains supplementary material, which is available to authorized users.

TachoSil demonstrated a strong sealing efficiency and marked elasticity in treating AAL. These results are consistent to that of the previously published animal experiment, suggesting the reliability of the presented in vitro model.