Clinical management using direct and derived parameters

In the past, left heart function was estimated from the level of CVP, clinical information and chest x-ray; cardiac output was estimated from mixed venous oxygen saturation or content. These indirect assessments frequently led to incorrect conclusions and irrationale therapy. Currently, direct and derived hemodynamic parameters have been invaluable in the diagnosis, management, and prognosis in critically ill patients. Continuous mixed venous oxygen saturation monitoring affords yet another valuable parameter to facilitate optimal patient care outcomes.