Severity stratification of septic shock according to noradrenaline requirement

Introduction

Septic shock (SS) is associated with 50% mortality. Severity is usually estimated from indexes of multiorgan dysfunction, 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.

Methods

An algorithm for hemodynamic treatment in SS, which established NA as the first drug (followed by dobutamine or adrenaline as required), was followed prospectively in all SS patients from December 1999 to August 2000. We evaluated Apache II and SOFA scores, maximum values for C-reactive protein (CRP) and lactate, hemodynamic profiles, and renal, respiratory and hepatic dysfunction. Patients were classified in three groups according to the maximum NA requirement: G1 (mild shock), NA < 0.1 μg/kg/min; G2 (moderate shock), NA from 0.1 to 0.3 μg/kg/min; and G3 (severe shock), NA > 0.3 μg/kg/min.

Results

Results are shown in the Table, expressed as mean ± standard deviation.

Table

Conclusion

Septic shock severity as assessed by noradrenaline requirement could aid in selecting patients for future trials. A NA requirement higher than 0.3 μg/kg/min is associated with high mortality.