Effects of volatile vs. propofol-based intravenous anesthetics on the alveolar inflammatory responses to one-lung ventilation: a meta-analysis of randomized controlled trials

The aim of this meta-analysis is to compare the potential effects of inhalation anesthetics with total intravenous anesthetics on alveolar cytokine expression and lung-related clinical outcomes in patients undergoing one-lung ventilation (OLV) for thoracic surgery. We retrieved the PubMed, EMBASE, and the Cochrane Library respectively to identify randomized controlled trials comparing different anesthetics (volatile anesthetics vs. intravenous anesthetics) on the pulmonary inflammatory response to OLV. The primary outcomes were the levels of alveolar concentrations of inflammatory cytokines. Eight randomized controlled trials that included 365 patients were screened. Overall, there were significant differences in the concentration of alveolar inflammatory mediators between volatile group and intravenous group, in which volatile group had lower levels of TNF-alpha (SMD -1.51; 95 % CI -2.15 to -0.87; p < 0.001), IL-6 (SMD -0.70; 95 % CI -0.99 to -0.41; p < 0.001) and IL-8 (SMD -1.32; 95 % CI -2.20 to -0.45; p = 0.003). The overall number of pulmonary complications in the volatile group was smaller (RR 0.42; 95 % CI 0.23-0.77; p = 0.005) and patients in that group had significantly abridged hospitalization stay (WMD -3.59 days; 95 % CI -5.70 to -1.48 days; p = 0.001). Inhalation anesthetics might be preferable in patients undergoing OLV for thoracic surgery and their protective effects might work via attenuating inflammatory responses.