Please see Bibliography of References for a list of abstracts, manuscripts and posters.
Renieris P, Gerovasili V, Poriazi M, Loukas T, Markaki V, Routsi C, Roussos C, Nanas S. Int Care Med. 2006;32(Supp 1):S98. Abstract 0371.
Introduction: Microcirculatory impairement in septic patients has long been implicated as a major causative factor of post-rescucitation multiple organ failure. The aim of the study was to investigate the microcirculatory alterations in septic patients with different severity of disease with the non invasive method of Near Infrared Spectroscopy.
Methods: We studied 39 (25 males/14 females, age 57±21) patients of a general ICU devided in 3 severity groups: SIRS (n=22), Severe Sepsis (n=9) and Septic Shock (n=8). We also studied 66 healthy volunteers. We used the InSpectra Near Infrared Spectroscopy device to continuously measure tissue oxygen saturation (StO2) at the thenar muscle before, during, and after a 3-minute occlusion of the brachial artery via pneumatic cuff. The decrease rate of the StO2 signal during the occlusion period was used as an index of tissue O2 consumption rate, and the increase rate of the StO2 signal after the cuff was released was used as an index of reperfusion to assess endothelial reactivity.
Results: Tissue oxygen saturation (StO2, %) was significantly lower in patients with SIRS or Severe Sepsis when compared to healthy volunteers ( 76±12 vs. 84±6 p=0.001 and 74±14 vs. 84±6 p=0.002 respectively). Oxygen consumption rate (StO2 decrease rate, %/min) was significantly lower in patients with Severe Sepsis when compared to healthy volunteers or patients with SIRS (15.9±52.4 vs. 31.2±9.1 p<0.001 and 15.9±52.4 vs. 26.5±13.1 p=0.006 respectively). Patients with Septic Shock also had a significantly lower oxygen consumption rate when compared to healthy volunteers or patients with SIRS (p<0.001 and p=0.002 respectively. Reperfusion rate (StO2 increase rate, %/min) was significantly lower in patients with SIRS of Severe Sepsis when compared to healthy volunteers (342±139 vs. 553±193 p<0.001 and 189±138 vs. 553±193 p<0.001 respectively). Patients with Septic Shock had significantly lower reperfusion rate when compared to healthy volunteers (p <0.001).
Conclusion: The microcirculation of septic patients is severely impaired, and this seems to depend upon severity of disease. Further studies should evaluate the potential role of Near Infrared Spectroscopy in guiding therapy and in providing prognostic information in this patient population.