Hemodynamic goal-directed therapy. A review

Patients can show arterial pressure and cardiac index within the normal range and still be in circulatory shock if oxygen and metabolic demand is increased or blood flow distribution is altered. Lactate is produced in anaerobic environment to preserve cellular integrity and physicians use its blood concentration value as a reliable marker of tissue hypoxia and energy failure. The authors review the recent literature on the importance of mixed venous oxygen saturation (SvO(2)) as an early sign of inadequate DO(2) that precede the lactate production