Sepsis and the Trauma Patient

Plasma levels of glutathione, alpha-tocopherol and lipid peroxides in polytraumatized patients; evidence for a stimulating effect of TNF alpha on glutathione synthesis

Prognosis and outcome of polytraumatized patients are determined by the possible development of multiple organ failure (MOF). Among the direct traumatic organ damage, it is caused by a systemic inflammatory reaction. This might be triggered by an activation of the inflammatory mediator cascade following hemorrhagic-traumatic shock as well as by oxygen-derived free radicals (ROS). The aim of our present study was to answer the following questions: 1. Is the "oxidative stress" measurable during the development of MOF after polytraumatic injury? 2. Is there a relation between the activation of the inflammatory mediator cascade and changes of the organism's antioxidative system? The study group included 26 patients (15 survivors, 11 non-survivors) suffering from severe polytraumatic injury (Hannover Polytrauma Score 12-63 points). Plasma levels of reduced (GSH) and oxidized (GSSG) glutathione alpha-tocopherol (TOC), lipid peroxides (expressed in terms of thiobarbituric acid reagible substances = TBARS), and tumor necrosis factor alpha (TNF) were measured each day from the point of admission on the ICU until the discharge or death of the patients. The following results were obtained: Independent from the outcome, we observed a continuous loss of plasma sulfhydryl groups and TOC. In the patients developing a MOF score > 5 on 10th day after injury (n = 6), a significant increase in plasma GSSG level was measurable. Additionally, a total loss of plasma GSH was seen in some of these patients indicating the collapse of the GSH-dependent antioxidative system. Similar changes were never observed in patients with MOF score < or = 5 on 10th day after injury (n = 15). In this group, a significant correlation between plasma TNF peaks and short time GSH boosts was obtained as a possible indicative for a stimulating effect of TNF on GSH synthesis. It can be concluded that processes of oxidative stress in connection with a consumption of endogenic antioxidants might be able to promote the development of MOF after polytraumatic injury.

Continuous infusion of Escherichia coli endotoxin in vivo primes in vitro superoxide anion release in rat polymorphonuclear leukocytes and Kupffer cells in a time-dependent manner

Continuous infusion of a nonlethal dose of Escherichia coli lipopolysaccharide (LPS) (0.5 mg/kg) induced early (3 h) accumulation of polymorphonuclear leukocytes (PMNL) in rat liver followed by later (30 h) greater extravasation of mononuclear phagocytes (MNP) (E. B. Rodriguez de Turco and J. A. Spitzer, J. Leukocyte Biol. 48:488-494, 1990). Nonparenchymal liver cells from rats treated for 3 and 30 h with LPS were recovered by centrifugal elutriation, yielding a 23-ml/min fraction (endothelial cells) and a 45-ml/min fraction (PMNL, Kupffer cells, and MNP), and compared for their capacity for basal and agonist-stimulated superoxide (O2-) production. Stimulation with phorbol myristate acetate and opsonized zymosan caused a dose-dependent release of O2- from the 45-ml/min fraction derived from rats treated for 3 h with saline, but not from the 23-ml/min fraction. Further purification of the 45-ml/min fraction by discontinuous density gradient centrifugation into a Kupffer and a PMNL fraction revealed that most of the agonist-induced O2- release was generated by infiltrating PMNL at this early time point of LPS infusion. By 30 h of LPS infusion, although enhancement of the phorbol-12-myristate-13-acetate- and opsonized zymosan-stimulated release of O2- was observed in the 45-ml/min fraction, but not in the 23-ml/min fraction, the maximum release of O2- was smaller than that observed in the rats treated for 3 h. Our results support the following conclusions: (i) after a 3-h LPS infusion, PMNL found in the liver in increased numbers are also highly primed for agonist-stimulated release of O2-, while Kupffer cell priming is of a lesser extent; (ii) after a 30-h infusion of LPS, infiltrating MNP found in the liver in increased numbers are primed for agonist-induced O2- release, while priming of PMNL has diminished; (iii) at both 3 and 30 h of LPS infusion, liver endothelial cells are not significantly primed for agonist-stimulated O2- release; and (iv) in vivo priming by LPS infusion at both 3 and 30 h was not reversed by the experimental method used for cell recovery (ca. 3 h), thus suggesting that in vivo LPS priming of O2- release may ultimately lead to severe impairment of liver function and metabolism observed during endotoxemia and sepsis if not therapeutically blocked at an early time point.