[Lipid peroxidation in critical patients].
Lipid peroxidation is a part of normal metabolism. The degree of peroxidation of membrane depends on the quantity and the quality of his fatty acids, both as components of the membrane, as constituents of the cellular environment. The magnitude of the changes which result in response to an exogenous load of hydrogen peroxides, shall depend, in part, on the pre-existing tissue levels of endogenous hydrogen peroxide. The exposure of the membrane to oxygen free radicals produced in excess, stimulates the process of lipid peroxidation. An update is made on lipid peroxidation in different nosological entities, with special emphasis on the special context of critical patients, and within this group, on the concept of ischemia-reperfusion. On the other hand, a brief review is made of the possible antioxidant defenses which may be used in the clinical situation, and a more extensive review is made of the correct analytical methodology to be used for determining the peroxidation.