Tissue perfusion assesment in shock

Abstract

Although new technologies have emerged and the tissue perfusion assessment has improved, shock remains with a high mortality ratio. Multiple organ dysfunction syndrome (MODS) due to tissue hypoperfusion is the best reason to explain this high mortality ratio in these patients. Hence, tissue perfusion assessment has the pivotal role in the shocked patient evaluation, because some therapeutic interventions can be performed. In this review, will be highlighted the main clinic signs and laboratories findings observed in hypoperfusion syndromes, including oxygen transport, oxygen delivery, oxygen consumption, oxygen extraction ratio, oxygen mixed venous saturation, arterial lactate end gastric-arterial CO2 gradient. These concepts are very important to understand and choose the best intervention for breaking events that are responsible for MODS development and death. The goals of resuscitation are also provided including mean arterial pressure above 65 mm Hg, mixed venous oxygen saturation above 65%, and lactate levels below 2 mMol/L. However, regional hypoperfusion can persist despite of restoring global hemodynamic variables. Hence, gastric-mucosal PCO2 could be a therapy-guide.