Monitoring of organ dysfunction in sepsis/systemic inflammatory response syndrome: Novel strategies

Sepsis and systemic inflammatory response syndrome-induced severe disruptio n of microcirculation and consecutive tissue hypoxia is considered a key fa ctor in the development of organ dysfunction and multiple organ failure. Th e conventionally measured global variables such as lactate or macrohemodyna mic parameters using a pulmonary artery catheter do not adequately mirror m icrocirculatory disturbances. Evaluation of the severity of microcirculator y distress and the effectiveness of resuscitation strategies requires new c linical technologies aimed at the microcirculation. It is anticipated that novel techniques such as optical spectroscopy and intelligent biosensors wi ll play a major role in the development of new monitoring systems. In gener al, the current monitoring of organ dysfunction is characterized by a trend from invasive to noninvasive and "safe" techniques, which provide bedside or even on-line monitoring and allow a more precise and earlier detection o f organ dysfunction. Techniques for the assessment of regional perfusion an d microcirculatory bioenergetics to direct therapeutic procedures are expec ted to refine and optimize clinical treatment of critically ill patients in the future. This article addresses the question of which variables should be monitored, what is feasible, and what is valid for therapeutic consequen ces. Recent developments in monitoring of macro- and microcirculation and o rgan-specific dysfunction, e.g., lung, kidney, are described with respect t o their advantages and limitations, and future directions are outlined.