Background. Air leakage is a common postoperative complication in pulmonary surgery, and surgical sealants have been developed to prevent or reduce the incidence of air leaks. In this study, we evaluated the efficacy of cross-linked gelatin glue (gelatin plus glutaraldehyde) in canine lung surgery models. Methods. Pulmonary fistulas and injuries were created in dogs and sealed with gelatin glue, fibrin glue, or fibrin glue with a polyglycolic acid (PGA) sheet. Seal-breaking pressures were measured in the fistula model, and pleural adhesions were assessed 28 days postoperatively in the lung injury model. Results. The seal-breaking pressures for canine cadaver and living lung surgeries (; the maximum pressures were 80 and 40 cm H₂O) were respectively: gelatin glue, 77 ± 6 and 32.3 ± 8.9cm H₂O; fibrin glue using spray, 39.2 ± 9.3 and 32 ± 6cm H₂O; fibrin glue using the rub-and-soak method, 35 ± 13.4 and 40 ± 0 cm H₂O; and fibrin glue with a PGA sheet, 55.5 ± 18.2 and 39 ± 2cm H₂O. In the lung injury model, there were no chest wall adhesions in the gelatin and fibrin glue alone groups, while strong adhesions were observed when treated with fibrin glue with a PGA sheet. Conclusions. Gelatin glue's sealing effect was superior to that of fibrin glue while preventing postoperative pleural adhesions. These findings suggest that gelatin glue may be effective as a surgical sealant or anti-adhesion materialin lung surgery
