Please see Bibliography of References for a list of abstracts, manuscripts and posters.
Nanas S, Renieris P, Gerovasili V, Poriazi M, Kritikos K, Aggelopoulos E, Kolias S, Zervakis D, Routsi C, Roussos C. Crit Care. 2006;10(Supp 1):S132. Abstract P318.
Introduction: Microcirculation is severely affected in sepsis. The non invasive evaluation of microcirculation and its association with the severity of sepsis has not been sufficiently studied.
Objective: To compare microcirculation parameters with sepsis severity.
Method: We studied 23 patients of a general ICU (age 56 ± 21 years) and 11 healthy volunteers (age 28 ± 4 years). Severity of sepsis was assessed with SOFA score (5 ± 2), APACHE II score (13 ± 5) and sepsis severity category (SIRS n=15, Severe Sepsis n=4 and Septic Shock n=4). InSpectra® Near Infrared Spectrometer was used to measure thenar muscle tissue oxygen saturation (StO2) before, during and after a 3−minute occlusion of the brachial artery. For the occlusion we used a brachial cuff and raised pressure 50 mmHg above measured systolic blood pressure. For the StO2 curve analysis we used InSpectra® Software Analysis program. For the statistical analysis we used SPSS 11.5 for Windows® and applied one−way ANOVA.
Results: StO2 base line value was significantly lower in patients with Severe Sepsis when compared to healthy controls (65±15 [49, 85] vs. 83±6 [72, 93] p=0,009). During the 3−minute occlusion of the brachial artery StO2 decrease rate was significantly lower in the Septic Shock group compared to healthy controls (15,5±6,3 [6,5 to 21,4] vs. 38,7±10,3 [22,1 to 52,9] p<0,001) as well as compared to SIRS group (15,5±6,3 [6,5 to 21,4] vs. 25,4±7,2 [17,8 to 43,4] p=0,036). StO2 decrease rate was also significantly lower in the Severe Sepsis group when compared to healthy controls (15,0±0,6 [14,4 to 16,0] vs. 38,7±10,3 [22,1 to 52,9] p<0,001) as well as compared to SIRS group (15,0±0,6 [14,4 to 16,0] vs. 25,4±7,2 [17,8 to 43,4] p=0,028). After the release of the occlusion, StO2 increase rate was significantly lower in the SIRS, Severe Sepsis and Septic Shock groups when compared to healthy controls (402,1±140,1 [206,2 to 653,5] vs. 643,8±241,4 [389,0 to 1275,0] p=0,002, 322,4±162,6 [185,5 to 520,5] vs. 643,8±241,4 [389,0 to 1275,0] p=0,005 and 219,3±136,3 [82,4 to 404,5] vs. 643,8±241,4 [389,0 to 1275,0] p<0,001 respectively).
Conclusions: Tissue oxygen saturation is related to the severity of sepsis. Additionally, tissue oxygen consumption is significantly lower in patients with Septic Shock or Severe Sepsis compared to healthy subjects or patients with SIRS. The lower StO2 increase rate in ICU patients may indicate affected endothelium reactivity.