Quantitation of lung sealing in the survival swine model

Small intercostal spaces and limited pleural space significantly limits the use of 12-mm stapling devices in pediatric thoracoscopic surgery. The goal of this study was to compare sealing of lung tissue by the 5-mm Ligasure (Valley Lab, Boulder, CO) device to a standard 12-mm Endo-GIA stapler (US Surgical, Norwalk, CT).

Institutional Animal Care and Use Committee (IACUC) approval was obtained (#A3-02). Sixteen 10-kg female swine were divided between 2 survival surgical groups. Lung biopsy sections of the lingula were taken by 2 methods: group A, left anterolateral thoracotomy employing a 12-mm Endo-GIA stapler and group B, left thoracoscopy employing the Ligasure 5-mm instrument. After a 7-day survival period, lung burst pressures were measured by flow-controlled insufflation into the trachea.

Burst pressure measurement reflects the first air leak. By Student's t test analysis there were no statistically significant differences between the burst pressures, biopsy weights, or operating times. Fifty percent (4 of 8) of the animals in group A (Endo-GIA), and 50% (4 of 8) of the animals in group B (Ligasure) developed the first air leak in the nonoperative lung. Two animals, one from each group, had evidence of intrapleural infections at the time of necropsy. These were asymptomatic and did not appear to affect burst pressure measurement.

After 7 days of healing, lung biopsy sites created with both the Ligasure and the Endo-GIA stapler have burst strengths equal to or greater than that of normal lung tissue in the swine survival model.