LAZAROID IMPROVES INTESTINAL BLOOD-FLOW IN THE RAT DURING HYPERDYNAMIC BACTEREMIA

Background Intestinal mucosal hypoperfusion and loss of barrier functi on during sepsis may contribute to maintaining the septic state. Free radicals are produced during sepsis and antioxidants improve survival from experimental sepsis. It is unclear whether endothelial cell injur y from free radicals results in altered microvascular reactivity. Laza roids are antioxidants which scavenge radicals and block lipid radical chain reactions. The authors sought to determine whether lazaroids al tered the intestinal microvascular responses to sepsis. Methods In viv o video microscopy was used to study the ileal microcirculation of the rat. Al (inflow) arteriolar diameter and flow, A3 (premucosal) arteri olar diameters, and cardiac output were measured. Lazaroid or vehicle was infused before a bolus injection of live Escherichia coli or salin e. Results Lazaroid alone had no effect on the intestinal vessels or h aemodynamics. E. coli caused vasoconstriction (Al, -21 per cent, A3, - 19) per cent of baseline) and hypoperfusion (-36 per cent) despite inc reased cardiac output (+31 per cent). Lazaroid significantly attenuate d both constriction(Al, -11 per cent; A3, 10 to -1 per cent) and hypop erfusion (-15 per cent), but did not increase cardiac output (30 per c ent). Conclusion E. coli bacteraemia led to intestinal vasoconstrictio n and hypoperfusion. Lazaroid reduced this effect without altering cen tral haemodynamic responses, suggesting that free radicals have a dele terious effect on the intestinal microcirculation during bacteraemia.