[Cardio-renal-axis--physiology, pathophysiology, and clinical relevance?]

[Hemodynamic target variables in the intensive care unit]

Despite broad availability, extended hemodynamic monitoring is used in practice only in the minority of critical care patients. Pathophysiological reasoning suggests that systemic perfusion pressure (and thereby arterial as well as central venous pressure), cardiac stroke volume, and the systemic oxygen balance are key variables in maintaining adequate organ perfusion. In line with these assumptions, several studies support that a goal-directed optimization of these hemodynamic variables leads to a reduction in morbidity and mortality. The appropriate monitoring modality should be selected following echocardiographic evaluation of biventricular function. Ideally, high-risk patients with limited right ventricular function should be monitored with a pulmonary artery catheter. In patients with preserved right ventricular function, transpulmonary thermodilution with special consideration of extravascular lung water seems to be sufficient to guide hemodynamic therapy.