(1602) Contrasting Epidemiology of Pediatric Sepsis and Septic Shock Based on Phoenix Versus IPSCC Criteria

Introduction: Sepsis remains a major cause of morbidity and mortality in children. In 2024, the Phoenix criteria for pediatric sepsis and septic shock were released, updating the 2005 International Pediatric Sepsis Consensus Conference (IPSCC) criteria. The Phoenix criteria reframed sepsis from the IPSCC definition of infection with systemic inflammatory response to that of infection with life-threatening organ dysfunction. We sought to contrast the epidemiology of sepsis and septic shock between the Phoenix and IPSCC criteria in a cohort of patients in the pediatric intensive care unit (PICU).

Methods: Retrospective cohort study of all patients admitted to the combined cardiac and medical/surgical PICU at our institution from July 2020 to June 2024. We defined infection as blood culture collection and initiation or broadening of parenteral antibiotics. Individual chart review was performed to assess for the presence of sepsis with or without septic shock based on either the IPSCC or Phoenix criteria. Repeat sepsis events in individual patients were excluded if occurred with 14 days of an index event.

Results: There were 507 sepsis events (366 in cardiac patients, 141 in medical/surgical patients) included in the analysis. 228 (45%) events met both Phoenix and IPSCC criteria, 149 (29%) met Phoenix only, and 130 (26%) met IPSCC only. 38% of IPSCC sepsis events also met criteria for septic shock. 85% of Phoenix sepsis events also met criteria for septic shock. 29% of Phoenix septic shock events met criteria solely based on milrinone administration. Case fatality for IPSCC sepsis and septic shock was 18% and 26%, respectively. Case fatality for both Phoenix sepsis and septic shock was 19%.

Conclusions: We observed that less than half of sepsis events met both IPSCC and Phoenix criteria, illustrating the shift in sepsis definition from infection with systemic inflammatory response to infection with life-threatening organ dysfunction. The Phoenix septic shock criteria, validated in emergency department patients, may be confounded in the cardiac PICU population by the high prevalence of routine milrinone administration. External validation of the Phoenix criteria in the cardiac PICU population is needed.