Organ failure and central nervous system

Summary Organ failure during acute or chronic illness can impair cerebral functions and manifest as coma or delirium; these are associated with adverse outcomes including prolonged hospitalization, increased morbidity and mortality. Despite high variability in the physiopathology of critical illness, many adverse conditions share common pathways which evolve in central nervous system (CNS) alterations. A deeper understanding of the mechanisms underlying the consciousness alteration induced by critical illness could help in preventing this serious complication. In fact a high percentage of patients suffer from long-term brain dysfunction, which manifests primarily as memory deficits and executive dysfunction. Interventions directed at reducing the occurrence of brain dysfunction during organ failure could improve patients outcome and seem promising, but further research is needed in order to assess the real efficacy of the different treatment options. In our review we examine the main clinical syndrome causing brain dysfunction, trying to elucidate the physiopathology and the processes that evolve into coma or delirium despite their different aetiology.