Redox imbalance in the critically ill

Abstract

The majority of deaths amongst critically ill patients requiring intensive care are attributable to sepsis and its sequelae: septic shock, the systemic inflammatory response syndrome (SIRS) and the acute respiratory distress syndrome (ARDS). Clinically, sepsis/SIRS and ARDS are characterised by disordered vascular control, manifest as systemic hypotension and peripheral vasodilation refractory to intravascular volume resuscitation and vasopressor therapy; and pulmonary hypertension. Experimental and clinical evidence demonstrates that these patients suffer from severe oxidative stress. Thus, our own and other groups have shown that the vascular pathology of sepsis/SIRS and ARDS is initiated through the uncontrolled production of reactive oxygen (ROS) and reactive nitrogen species (RNS) which modulate inflammatory cell adhesion and cause direct injury to endothelium.