Capillary Leak Index Versus Conventional Biomarkers in Predicting Sepsis-Related Outcomes

Inclusion Criteria: Age ≥ 18 years. Postoperative secondary peritonitis requiring ICU admission, with clinical evidence of: Diffuse or localized abdominal pain/tenderness. Peritoneal signs (e.g., guarding, rigidity, rebound tenderness). Imaging or intraoperative confirmation of purulent/exudative intra-abdominal fluid. Systemic inflammation (e.g., fever, leukocytosis, or vasopressor requirement). Sepsis diagnosis per Sepsis-3 criteria: Suspected/confirmed infection with acute increase in SOFA score ≥2 points (6). Anticipated ICU stay ≥48 hours postoperatively. Exclusion Criteria: * Pregnancy * Advanced liver disease (Child-Pugh class B or C) that might independently affect albumin levels * Advanced kidney disease (CKD stage 4 or 5) or patients on chronic dialysis * Expected mortality within 48 hours of ICU admission * Patients with primary peritonitis or tertiary peritonitis * Immunocompromised patients (e.g., on chronic immunosuppressive therapy, solid organ transplant recipients, patients with HIV and CD4 count \<200/mm³) * Patients with pre-existing systemic inflammatory diseases that might affect baseline CRP levels * Patients participating in interventional trials that might affect outcomes