One-lung ventilation during thoracoabdominal esophagectomy elicits complement activation

One-lung ventilation (OLV) during thoracoabdominal esophagectomy may induce an inflammatory response that can contribute to the induction and propagation of frequently occurring postoperative respiratory distress. Markers of such a response might be detected in the pulmonary as well as in the systemic circulation. Inflammation and tissue damage may be key pathogenetic pathways and we hypothesized that 1-lung ventilation may induce an inflammatory cascade reflected by markers for such a response.

Thirty patients with esophageal cancer were randomized to OLV (n = 16) or 2-lung ventilation (TLV; n = 14) during the thoracic part of the operation. Compounds involved in inflammation and coagulation were measured perioperatively and during the 1st, 2nd, 3rd, and 10th postoperative d.

During the perioperative phase, the proinflammatory cytokine interleukin-6 and thrombin, measured as thrombin-antithrombin complexes, started to increase. Thrombin, which can induce complement activation, peaked at the end of surgery and interleukin-6 at the 1st to 2nd postoperative d, but there were no differences between the OLV and TLV groups. C3a and terminal complement complex (TCC) started to increase on the 2nd postoperative d and continued to do so for the rest of the study period. The increase of TCC was significantly higher in the OLV group compared to the TLV group, whereas C3a attained similar levels in the 2 groups.

OLV is associated with an augmented inflammatory response as reflected by the activation of the TCC. This may induce pulmonary tissue damage and recruitment of inflammatory cells.