[Significance of selenium in intensive care medicine. Clinical studies of patients with SIRS/sepsis syndrome]

Abstract

Selenium is an essential component of the intracellular antioxidant system as a structural component of the active center of the glutathione peroxidase enzymes. These selenoenzymes play a major role in protecting cells against peroxidation, especially lipid peroxidation and selenium seems to play a direct role in the regulation of inflammatory processes. In conditions of systemic inflammatory response or sepsis, patients are exposed to severe oxidative stress. These patients already have both, a decreased plasma selenium and glutathione peroxidase activity at admission to the ICU as has been shown in several studies. The degree of selenium deficiency is correlated with the severity of disease and the incidence of mortality. The reason for the low plasma selenium levels is unknown. Especially it would be of interest a) if the low plasma selenium is the consequence of the systemic inflammatory response with distribution of selenium in other compartments of the body, b) most important, whether the substitution of selenium might improve the outcome and decrease the mortality rate of these patients. In 2 independently performed intention-to-treat studies including patients with systemic inflammatory response syndrome or sepsis a beneficial effect of selenium supplementation on multiple organ function and outcome could already be demonstrated as well as a tendency of an improved mortality rate. A prospective analytical study clearly could demonstrate the inverse relationship between low plasma selenium and morbidity and mortality of patients with SIRS/sepsis. The results of these studies are so convincing, that we propose a randomized, prospective, double blind multicenter phase-III study including patients with systemic inflammatory response syndrome or sepsis to investigate, whether a high-dose selenium substitution in addition to the recommended treatment strategies for patients with sepsis improves outcome and mortality rate of these patients.