Hour-1 Sepsis Bundle: Updated Evidence.

Sepsis and septic shock remain leading causes of disability, mortality and healthcare utilization worldwide. Increasing evidence has established sepsis as a time-dependent emergency in which delays in diagnosis and treatment are associated with worsening organ dysfunction and increased mortality. To standardize early management, the Surviving Sepsis Campaign (SSC) developed evidence-based care bundles, culminating in the current Hour-1 Bundle, which emphasizes rapid implementation of key diagnostic and therapeutic interventions. This narrative review critically examines the scientific rationale, clinical evidence, implementation challenges, and future perspectives surrounding the SSC Hour-1 Bundle. Lactate remains a valuable marker of illness severity and treatment response, although its interpretation requires consideration of multiple non-hypoperfusion-related mechanisms. Blood cultures represent the microbiological gold standard, while emerging rapid diagnostic technologies are transforming pathogen identification and antimicrobial stewardship. Early effective antimicrobial therapy remains strongly associated with improved outcomes, although balancing prompt treatment with antimicrobial stewardship remains challenging. Fluid resuscitation strategies have evolved from fixed-volume approaches toward individualized assessment of fluid responsiveness and tolerance, whereas early vasopressor initiation is increasingly recognized as complementary to fluid administration. Although observational studies frequently associate bundle adherence with improved outcomes, real-world compliance remains variable and evidence supporting strict one-hour completion targets remains heterogeneous. Future developments are expected to move beyond standardized protocols toward personalized sepsis management integrating rapid diagnostics, immune phenotyping, advanced haemodynamic monitoring, and artificial intelligence-driven clinical decision support. These innovations may enable more precise therapeutic strategies while preserving the fundamental principles of sepsis management, that remain the cornerstone of contemporary sepsis care.