RESUMO
PURPOSE: We performed lung volume reduction surgery (LVRS) in an experimental model using a simple stapling technique (SST) for pulmonary emphysema. The technique uses a stapler to isolate the affected lung from the remaining lung instead of removing it. We performed the present experiment using dogs to study the effects and safety of LVRS using the SST. METHODS: Pulmonary emphysema was induced in 12 dogs with papain. They were divided into three groups: those operated on with SST composed the operation (Op) group; those receiving an experimental thoracotomy composed the sham-operation (Sham-op) group; and those not operated on composed the nonoperation (Non-op) group. Respiratory function was compared among the groups before induction of emphysema (baseline), after induction of emphysema (preoperation), and at 8 weeks after the operation (postoperation Op and Sham-op groups only). The lung was removed and histologically examined 8 weeks after the SST operation. RESULTS: In the Op group, alteration in forced expiratory volume (FEV) 0.5%, airway resistance (Raw) and specific airway conductance (sGaw) showed significantly favorable results. Histologically, the isolated area was widely replaced by fibrous tissue with numerous blood vessels in the circumference in the Op group; no signs of infection such as polykaryoleukocytes or microabscesses were observed in any of the samples. CONCLUSION: The LVRS for pulmonary emphysema using a simple stapling technique improved the expiratory flow and alleviated airway resistance. The isolated remaining lung was well organized without any infectious events or secondary adversity, thus demonstrating the safety of this technique. From these results, this technique is therefore suggested to be effective and applicable to clinical use.
