Surgical wound-site inflammation: video-assisted thoracic surgery versus thoracotomy

OBJECTIVES: Mechanical trauma occurring during pulmonary resection through both video-assisted thoracic surgery (VATS) or thoracotomy causes profound alterations in cytokines and the cellular network. The aim of this study was to analyse biological changes occurring in both the microenvironment (wound site) and macroenvironment (systemic circulation) following pulmonary lobectomy via the VATS or thoracotomic approach. METHODS: From October 2016 to July 2017, 30 patients with clinical Stage I lung cancer were recruited. In 12 cases (the VATS group), surgery was performed through a video-assisted thoracoscopic approach and in 15 cases (the thoracotomy group) through a muscle-sparing minithoracotomy. Following the skin incision, the wound was irrigated with a saline solution (20 ml) and then collected. After the pulmonary resection, the surgical incision was re-irrigated. The number of polymorphonuclears, granulocytes and lymphocytes in the fluids was determined by the fluorescence activated cell sorting (FACS) analysis. Cytokine profiles of interleukin (IL)-6, tumour necrosis factor (TNF)-α, IL-1 and IL-8 from sera and fluids were detected by the enzyme linked immunosorbent assay (ELISA) assay. Functional results were evaluated through spirometry, and pain was assessed using the visual analogue scale. RESULTS: In the postoperative fluids of the VATS group, fewer polymorphonuclears were seen compared to the thoracotomy group (P = 0.001), as well as a decreased percentage of granulocytes (P = 0.01) and a parallel increased lymphocytes fraction (P = 0.001). Only the systemic IL-1β levels were significantly lower in postoperative sera of the VATS group (P = 0.038). No differences were observed regarding other cytokines. CONCLUSIONS: The local microenvironment during VATS differs from that of thoracotomy by not producing the same inflammatory phenotype. The clinical efficacy of a less invasive surgical approach is confirmed by a reduced inflammation of the systemic and local districts.