ACTIVATION OF THE L-ARGININE NITRIC-OXIDE PATHWAY IN SEVERE SEPSIS

Aims-To determine in children with sepsis syndrome and septic shock th e time course of nitric oxide metabolites: nitrate and nitrite (nitrog en oxides). To determine whether serum concentrations of nitrogen oxid es distinguished those children who died from sepsis from those who su rvived; those who required prolonged inotropic support compared with t hose who did not; and whether there was any relationship of the levels of nitrogen oxides to markers of tissue perfusion. Methods-Nitrogen o xides were measured in 30 children with sepsis syndrome or septic shoc k at admission, 12, 24, and 48 hours. A non-septic control group had s erum nitrogen oxides measured at admission. Markers of haemodynamics a nd tissue perfusion measured were mean arterial pressure, blood lactat e, base deficit, gastric intramucosal pH, and deltaCO(2) (DCO2: the di fference between arterial and gastric intraluminal carbon dioxide tens ions). Inotrope doses, number of organ systems failing at 48 hours, an d outcome as survival were recorded. Results-Children with sepsis had increased nitrogen oxide concentrations at presentation compared with a group of non-septic controls. Children with organ failure at 48 hour s had higher serum nitrogen oxide concentrations than those with sepsi s uncomplicated by organ failure at 48 hours. There was no difference in nitrogen oxide when patients were subgrouped according to the recei pt of inotropes at 48 hours, and no association with markers of tissue perfusion, or survival. Conclusions-White this study shows that nitri c oxide production is increased in sepsis in children, there was a lim ited relationship with clinically important markers of illness severit y and no relationship to survival.