Abstract
IntroductionThe prognostic value of continuous monitoring of tissue oxygen saturation (StO2) during early goal-directed therapy of critically ill patients has not been investigated. We conducted this prospective study to test the hypothesis that the persistence of low StO2 levels following intensive care admission is related to adverse outcome.MethodsWe followed 22 critically ill patients admitted with increased lactate levels (>3 mmol/l). Near-infrared spectroscopy (NIRS) was used to measure the thenar eminence StO2 and the rate of StO2 increase (RincStO2) after a vascular occlusion test. NIRS dynamic measurements were recorded at intensive care admission and each 2-hour interval during 8 hours of resuscitation. All repeated StO2 measurements were further compared with Sequential Organ Failure Assessment (SOFA), Acute Physiology and Chronic Health Evaluation (APACHE) II and hemodynamic physiological variables: heart rate (HR), mean arterial pressure (MAP), central venous oxygen saturation (ScvO2) and parameters of peripheral circulation (physical examination and peripheral flow index (PFI)).ResultsTwelve patients were admitted with low StO2 levels (StO2 <70%). The mean scores for SOFA and APACHE II scores were significantly higher in patients who persisted with low StO2 levels (n = 10) than in those who exhibited normal StO2 levels (n = 12) at 8 hours after the resuscitation period (P < 0.05; median (interquartile range): SOFA, 8 (7 to 11) vs. 5 (3 to 8); APACHE II, 32(24 to 33) vs. 19 (15 to 25)). There was no significant relationship between StO2 and mean global hemodynamic variables (HR, P = 0.26; MAP, P = 0.51; ScvO2, P = 0.11). However, there was a strong association between StO2 with clinical abnormalities of peripheral perfusion (P = 0.004), PFI (P = 0.005) and RincStO2 (P = 0.002). The persistence of low StO2 values was associated with a low percentage of lactate decrease (P < 0.05; median (interquartile range): 33% (12 to 43%) vs. 43% (30 to 54%)).ConclusionsWe found that patients who consistently exhibited low StO2 levels following an initial resuscitation had significantly worse organ failure than did patients with normal StO2 values, and found that StO2 changes had no relationship with global hemodynamic variables.
Highlights
The prognostic value of continuous monitoring of tissue oxygen saturation (StO2) during early goal-directed therapy of critically ill patients has not been investigated
The mean scores for Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were significantly higher in patients who persisted with low StO2 levels (n = 10) than in those who exhibited normal StO2 levels (n = 12) at 8 hours after the resuscitation period (P
There was no significant relationship between StO2 and mean global hemodynamic variables (HR, P = 0.26; mean arterial pressure (MAP), P = 0.51; ScvO2, P = 0.11)
Summary
The prognostic value of continuous monitoring of tissue oxygen saturation (StO2) during early goal-directed therapy of critically ill patients has not been investigated. The analysis of changes in StO2 during a vascular occlusion test, such as a brief episode of forearm ischemia, has been used as a marker of integrity of the microvasculature – in particular, the StO2 recovery after the vascular occlusion test [5,6,7] These reports, have studied the correlation of intermittent StO2 measurements and outcome where there are only limited data describing whether continuous monitoring of StO2 during the early resuscitation phase is related to morbidity or to mortality
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have