Septic shock (SS) is associated with 50% mortality. Severity is usually estimated from indexes of MODS, but hemodynamic dysfunction, despite its main role, has traditionally been underscored. The aim of this study was to test a severity classification for SS according to noradrenaline (NA) requirements.
An algorithm for hemodynamic treatment in SS, which established NA as the initial vasoactive drug (followed by dobutamine or adrenaline as required), was followed prospectively in all SS patients from December 1999 to August 2000. We evaluated APACHEII and SOFA scores, maximum values for C-reactive protein (CPR) and lactate, hemodynamic profiles, and renal, respiratory and hepatic dysfunction. Patients were classified in three groups according to the maximum NA requirement: mild, NA <0.1 μg/kg/min; moderate, NA 0.1-0.3 μg/kg/min; and severe, NA >0.3 μg/kg/min.
Results are expressed as mean ± SD (Table).
Noradrenaline requirement >0.3 μg/kg/min is associated with high mortality in SS. Based on these results, a new and strong criterium for severe septic shock is proposed. We also showed the feasibility of applying a predefined algorithm for hemodynamic treatment.