Tissue Oxygenation Measurement in Patients with Sepsis Compared to the Lactate Levels and Hemodynamical Monitoring

Abstract

Near-infrared spectroscopy (NIRS) is a noninvasive method for measuring tissue oxygenation. The method allows for monitoring tissue perfusion in shock by revealing tissue hemoglobin oxygen saturation (StO₂). The current study aims to compare tissue oxygenation levels with hemodynamical monitoring and lactate levels in patients in severe shock. Study encompasses 19 patients treated in intensive care unit (ICU) at Alexandrovska University Hospital. Ten of the patients cover the criteria for severe sepsis, the remaining nine patients have no data for septic condition. In both groups of patients tissue oxygenation levels measured with INVIOS monitor, mean arterial pressure (MAP), oxygen saturation in mixed venous blood (SvO₂) and lactate levels within 72 h of intensive care unit admission are compared. The patients with severe sepsis have significantly lower levels of StO₂ in comparison with patients without sepsis. Tissue oxygenation levels correspond to the mean arterial pressure levels, oxygen saturation in mixed venous blood. StO₂ levels in the current study do not correlate significantly with the lactate levels in patients with sepsis. Near-infrared spectroscopy as StO₂ levels correlate with the hemodynamical monitoring in patients with severe sepsis, but do not correlate significantly with the severity of the disease. This data might indicate that tissue oxygenation monitoring has clinical significance in patients with sepsis. Further profound studies are necessary for assessing the role of tissue oxygenation monitoring in the early phase of resuscitation in septic patients.