Lower limb ischaemia–reperfusion injury causes endotoxaemia and endogenous antiendotoxin antibody consumption but not bacterial translocation

Background It has been suggested that reperfusion of the acutely ischaemic lower limb alters gut permeability. The effect of lower limb ischaemia-reperfusion on systemic endotoxin and antiendotoxin antibody concentrations and the incidence of bacterial translocation was investigated. Methods Systemic endotoxin and antiendotoxin antibody concentrations were measured in five groups of male Wistar rats: control, after 3 h of bilateral hind limb ischaemia alone, and after 3 h of bilateral hind limb ischaemia followed by 1, 2 or 3 h of reperfusion. A second experiment examined translocation of indigenous bacteria following 2 h of reperfusion in a similar model. Results Ischaemia followed by reperfusion for 1, 2 or 3 h caused a significant increase in plasma endotoxin concentration to mean(s.e.m.) 10.0(3.0), 44.8(19.2) and 20.2(6.2) pg/ml compared with that in control animals (2.58(0.91) pg/ml) or animals in the ischaemia alone group (1.2(0.8)pg/ml) (P<0.05). This was associated with a significant reduction in endogenous antiendotoxin antibody (immunoglobulin (Ig)G and IgM) concentration. No significant bacterial translocation was detected in any of the groups studied. Conclusion These results demonstrate that a remote and isolated ischaemia-reperfusion injury to the lower limb, in the absence of infection or bacterial translocation, causes endotoxaemia. Further studies are needed to evaluate the role of endogenous antiendotoxin antibodies in this situation.