Immunomodulatory Effects of Anesthetics during Thoracic Surgery

Background. One-lung ventilation (OLV) during thoracic surgery may induce alveolar cell damage and release of proinflammatory mediators. The current trial was planned to evaluate effect of propofol versus isoflurane anesthesia on alveolar and systemic immune modulation during thoracic surgery. Methods. Fifty adult patients undergoing open thoracic surgery were randomly assigned to receive propofol (n = 25) or isoflurane (n = 25) anesthesia. The primary outcome measures included alveolar and plasma concentrations of interleukin-8(IL-8) and tumour necrosis factor-α (TNF-α), whereas secondary outcome measures were alveolar and plasma concentrations of malondialdehyde (MDA), superoxide dismutase (SOD), and changes in alveolar albumin concentrations and cell numbers. Results. Alveolar and plasma concentrations of IL-8 and TNF-α were significantly lower in the isoflurane group, whereas alveolar and plasma concentrations of MDA were significantly lower in the propofol group. Alveolar and plasma SOD levels increased significantly in the propofol group whereas they showed no significant change in the isoflurane group. Furthermore, the isoflurane group patients developed significantly lower alveolar albumin concentrations and cell numbers. Conclusion. Isoflurane decreased the inflammatory response associated with OLV during thoracic surgery and may be preferable over propofol in patients with expected high levels of proinflammatory cytokines like cancer patients.