Septic shock is a major cause of morbidity and mortality in critically ill children. Continuous renal replacement therapy (CRRT) is increasingly used as adjunctive support in pediatric septic shock to improve hemodynamic stability, modulate inflammatory responses, and correct metabolic disturbances. However, evidence regarding optimal indications, timing, and clinical outcomes of early CRRT use in children remains limited.

This prospective observational study aims to evaluate associations between early CRRT use and changes in hemodynamics, organ dysfunction, inflammatory cytokine levels, and short-term clinical outcomes in pediatric patients with septic shock admitted to pediatric intensive care units

This is a prospective observational cohort study conducted in pediatric intensive care units (PICUs). Children diagnosed with septic shock who receive early continuous renal replacement therapy (CRRT) as part of routine clinical care will be consecutively enrolled.

Baseline assessments will be performed prior to CRRT initiation and include clinical status, hemodynamic parameters, echocardiographic indices, laboratory markers, and inflammatory cytokine levels. Follow-up assessments will be conducted at predefined time points after CRRT initiation.

CRRT initiation, modality, and management will follow institutional protocols and treating physician judgment. No randomization or intervention assignment is performed. Patients will be followed during PICU stay and up to Day 28 after PICU admission

Inclusion Criteria:

• Age from 1 month to <18 years

• Diagnosis of septic shock according to Phoenix Sepsis Criteria, defined as:

  • Phoenix Sepsis Score ≥ 2, and
  • Presence of circulatory dysfunction

• Fulfillment of at least one of the following:

  • Acute kidney injury KDIGO stage 2 or higher
  • Requirement for vasoactive support with Vasoactive-Inotropic Score (VIS) ≥ 50

• Admission to a Pediatric Intensive Care Unit (PICU)

• Written informed consent obtained from parent(s) or legal guardian(s)

Exclusion Criteria:

• Expected survival <24 hours at time of screening

  o End-stage organ failure, including: End-stage renal disease requiring chronic dialysis or eGFR <15 mL/min/1.73 m²

  • End-stage liver disease
  • End-stage heart failure

• Known immunosuppression, including HIV infection or primary immunodeficiency disorders

• Emergency indications for CRRT unrelated to septic shock (e.g., severe hyperkalemia, severe dysnatremia, symptomatic uremia, or fluid overload >10%)

• PICU length of stay <24 hours

• CRRT duration <6 hours

Pediatric patients with septic shock admitted to the PICU and receiving early continuous renal replacement therapy as part of routine clinical care