21 Mar 08
Cryptic septic shock: A sub-analysis of early, goal-directed therapy
By M W Donnino, B Nguyen, G Jacobsen, M Tomlanovich and E Rivers
Despite the current definition of septic shock, patients with normal or high blood pressure may still display global tissue hypoxia. The following study evaluates early, goal-directed therapy (EGDT) in patients with severe sepsis in the absence of hypotension.
METHODS
This is a post-hoc anlysis of patients presenting to an urban ED in severe sepsis and septic shock. Patients were included if they had SIRS critieria, lactic acidosis (> 4 mmol/liter), and mean arterial pressure (MAP) > 100 mm Hg. Patients were randomized to conventional care (inclusive of central venous pressure (CVP) monitoring) or EGDT. EGDT consisted of 6 hours of resuscitation to goals of CVP between 8–12, MAP between 65–90, and central venous oximetry (ScvO2) greater than 70%.
RESULTS
There was no difference in mean MAP (116.0 mm Hg in the control and 117.6 mm Hg in the treatment group), and there was no difference in APACHE, MODS, and SAPS scores between groups. Forty-eight patients (23 in the control group and 25 in the EGDT group) were analyzed. The mortality was 60.9% in the control group compared to 20% in the EGDT group [p < 0.004]. The mean initial ScvO2 was 45 % and 44 % in the control and treatment groups respectively. At six hours, ScvO2 was higher in the EGDT (76% versus 59%), whereas the lactate and MODS score were reduced (p < 0.05). The EGDT group received more total intravenous fluids than the treatment group (p < 0.05) during the first six hours. At sixty days, mortality in the control (70%) and in the treament group (24%) remained significant (p=0.002).
CONCLUSIONS
This study confirms that patients with severe sepsis accompanied by lactic acidosis may display global tissue hypoxia in the absence of hypotension. Early identification and goal-directed therapy of this subgroup leads to a reduction in morbidity and mortality.