Effect of EGDT on tissue perfusion in patients with septic shock

Abstract

Objective To observe the effect of early goal directed therapy (EGDT) on tissue perfusion,microcirculation and tissue oxygenation in patients with septic shock.Methods A prospective observational study was carried out in 20 patients with early septic shock admitted to ICU within 24 hours after onset.Patients with one of following conditions,including stroke,brain injury,other types of shock,severe heart failure,acute myocardium infarction,ages below 18,pregnancy,terminal stage of disease,cardiac arrest,extensive bums,mouth bleeding,oromandiblular dyetonia (difficult to open the mouth),and the time elapsed over 24 hours after onset of septic shock,were excluded.The eligible patients were treated with the standard procedure of EGDT.The partial pressure of transcutaneous oxygen and carbon dioxide (PtcO2,PtcCO2) was monitored and hemodynamic data were recorded.Sidestream dark field imaging device was applied to detect the sublingual microcirculation.Hemodynamics,tissue oxygen,and sublingual microcirculation were compared before treatment and after EGDT.When the variables met the normal distribution,t test was applied.Otherwise,Wilcoxon test was used.Correlation between variables was analyzed with Pearson Correlation Analysis.Results Of 20 patients,19 met all 4 elements in criteria of EGDT after treatment and were eligible for study.PtcO2 and PtcCO2 were monitored in 19 patients.Sublingual microcirculation was obtained in four of them.(1) After the criteria of EGDT were entirely met,PtcO2 increased from (62.7 ± 24.0) mm Hg to (78.0 ± 30.9) mm Hg (P ＜ 0.05) ; tissue oxygenation index (PtcO2/FiO2) was (110.7 ± 60.4) mm Hg before treatment and (141.6 ± 78.2) mm Hg after EGDT (P ＜ 0.05).PtcCO2 and PaCO2 gap (difference between PtcCO2 and PaCO2) decreased significantly after EGDT (P ＜ 0.05).(2) Both proportion of small vessels with perfusion (PVP) and microcirculatory flow index of small vessels (MFI) showed a trend of increase after EGDT,but there were no significant differences between pre-and post-EGDT (P was 0.051 and 0.074 respectively).(3) PtcO2,PtcO2/FiO2,and PtcCO2 were not linearly related to central venous saturation,lactate,oxygen delivery,and oxygen consumption (All P ＞ 0.05).Conclusions Peripheral perfusion improved after EGDT in patients with septic shock but those hemodynamic variables might not exactly reflect the authenticity of global perfusion. Key words: Transcutaneous pressure of oxygen; Transcutaneous pressure of carbon dioxide; Microcirculation; Septic shock; Early goal directed therapy; Tissue perfusion; Tissue oxygenation; Sidestream dark field imaging