Thoracic duct in patients with multiple organ failure: No major route of bacterial translocation

Objective To determine whether translocation of bacteria or endotoxin occur red into the thoracic duct in patients with multiple organ failure (MOF). Summary Background Data Translocation of bacteria or endotoxin has been pro posed as a causative factor for MOF in patients without an infectious focus , although it has rarely been demonstrated in patients at risk for MOF. Mos t studies have investigated the hematogenic route of translocation, but It has been argued that lymphatic translocation of bacteria or endotoxin by th e thoracic duct is the major route of translocation. Methods The thoracic duct was drained for 5 days in patients with MOF cause d either by generalized fecal peritonitis (n = 4) or by an event without cl inical and microbiologic evidence of infection (n = 4). Patients without MO F who were undergoing a transthoracic esophageal resection served as contro ls. In lymph and blood, concentrations of endotoxin, proinflammatory cytoki nes, and antiinflammatory cytokines were measured. Results Endotoxin concentrations in lymph and blood of patients with MOF ra nged from 39 to 63 units per liter and were not significantly different fro m concentrations in patients without MOF. The quantity of endotoxin transpo rted by the thoracic duct in the study group was small. In patients with MO F, low levels of proinflammatory cytokines and high levels of antagonists o f these cytokines were found. Conclusion This study provides evidence that translocation (especially of e ndotoxin) occurs into the thoracic duct. However, these data do not support the concept that the thoracic duct is a major route of bacterial transloca tion in patients with MOF.