Beta-Lactam Antibiotics InitiaL ExpoSure OptimisEd in CriticallY Ill Patients with SEpsis

Inclusion Criteria: * ≥18 years of age * Receiving intravenous antibiotic therapy of the target drugs (including continuous infusion of beta-lactam antibiotics) * Primary infection * Admitted to the ICU * Meeting the Sepsis-3 criteria for septic shock: sepsis in addition to shock requiring the start of vasopressors to maintain a mean arterial pressure 65 mmHg or greater, and a serum lac tate level greater than 2.0 mmol/L following "adequate fluid resuscitation". Exclusion Criteria: * Patient or legal representative not available to give informed consent within 72 hours after admittance * Pregnancy * Admittance for burn wounds * Patients receiving target antibiotics only as prophylaxis within the context of Selective Diges tive tract Decontamination (SDD) * Enrolment in another interventional trial * Patient received the study antibiotic for more than 24 hours before inclusion * Patient receiving extracorporeal membrane oxygenation (ECMO) * Patient is already treated with a double dose of antibiotics based on suspected infection