Utility of Sodium Lactate Infusion During Septic Shock

Inclusion Criteria: * Presence of septic shock * requiring vascular filling within 12 hours after introduction of Noradrenaline. Septic shock is defined as sepsis with persistent hypotension requiring the administration of vasopressors to maintain RTE \> 65mmHg. * social insurance Exclusion Criteria: * pregnancy * cardiac arrest * more than 50ml/kg of fluid loading * chronic renal failure with chronic hemodialysis or the investigators estimate a need for renal replacement therapy in the following 24hrs * child C or acute liver failure with PT\<40% (unless AVK) * plasmatic sodium \<120 or \>145mmol/l * metabolic alkalosis with pH\>7.45