Phoenix Sepsis Score in Children Transported to PICUs

Source: Carter, Michael J. et al. Evaluation of Phoenix sepsis score criteria: exploratory analysis of characteristics and outcomes in an emergency transport PICU cohort from the United Kingdom, 2014–2016. Pediatr Crit Care Med. 2025;26(2):e186-e196; doi: 10.1097/PCC.0000000000003682.Investigators from multiple institutions conducted a retrospective study to characterize Phoenix Sepsis Scores (PSS) in children transported from community hospitals to PICUs because of suspected or confirmed infection and evaluate the association between PSS and poor outcomes in these patients. For PSS, quantitative criteria are used to score dysfunction in 4 organ systems—cardiovascular, respiratory, coagulation, and neurologic—to define “sepsis” and “septic shock” in children with suspected infection. For each component of the scoring system, the worst value obtained during the first 24 hours of the hospital encounter is used. An overall score of ≥2 is used to define sepsis, and a score of ≥2 with at least 1 point in the cardiovascular domain denotes septic shock. For the current study, data prospectively collected in a cohort of children <16 years old transported to 1 of 4 PICUs in England between 2014 and 2016 with suspected or confirmed infection were analyzed. The data included demographics, clinical characteristics, laboratory values, and outcomes. Patients were classified as having definitive or probable bacterial or viral infections based on specific criteria and grouped into diagnostic groups (bronchiolitis, meningoencephalitis, pneumonia, severe sepsis, and septic shock). The PSS in these children were calculated using the available data, with some specific component scores inferred if the available data could not be directly used. The proportion of patients with sepsis and septic shock was determined for different diagnostic groups. The association between a poor outcome, defined as death or need for mechanical ventilation at 30 days, and a PSS ≥2 also was evaluated.Data were analyzed on 444 children with confirmed or suspected infection. The median PSS in the study participants was 2; 260 (58.6%) met PSS criteria for sepsis, and 177 (68.1% of those with sepsis defined by a PSS ≥2) met criteria for septic shock. The rate of sepsis based on a PSS ≥2 among patients in different diagnostic groups included 55.2% for those with bronchiolitis, 57.6% of those with meningoencephalitis, 63.8% of children with pneumonia, 82.6% of those with septic shock, and 60% of patients with a diagnosis of severe sepsis. Among those with culture proven sepsis, 79.3% had a PSS ≥2. PSS scores were significantly higher among 27 children who died compared to survivors (median scores, 4 and 2, respectively; P = 0.004), and in those who died or required mechanical ventilation at 30 days (P <0.001).The authors conclude that a majority of patients transported to a PICU because of suspected infection met PSS criteria for sepsis.Dr Miller-Smith has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.The definition of pediatric sepsis and septic shock has been evolving, with many attempts at identifying accurate criteria. (See AAP Grand Rounds. 2017;38[1]:11.)1 In 2024, a Society of Critical Care Medicine expert workgroup developed the PSS and provided criteria to define sepsis and septic shock in children.2,3 The authors of the PSS strove to create a tool that could be utilized in high- and low-resource settings and across the health care continuum.2 Because >80% of pediatric patients with sepsis present initially before the PICU encounter,4 the score was derived from patients within the ED, general floor, and PICU.2 The PSS already has been externally validated by multiple groups, demonstrating better correlation with mortality than the old criteria.5 To assure validity, the PSS authors have welcomed additional validation studies from multiple clinical domains.Until the current study, investigators had not looked at the PSS score for children transferred from community hospitals to a PICU. In this retrospective study, researchers assessed data obtained prior to PICU admission. They found that more than half of patients transferred to a PICU because of suspected infection had PSS-defined sepsis. PSS-defined sepsis was associated with higher mortality and fewer ventilator-free days. Participants in this study, however, were more likely to have sepsis than the original cohort. The utilized database is likely a higher acuity subset than in the derivation study, as patients were captured only if they had invasive arterial and central venous access. Additionally, these patients were more frequently ventilated and sedated, potentially impacting their PSS and/or indicating higher acuity. Despite differences in patient characteristics, the score appears reasonable and useful in defining sepsis. The externally validated PSS will potentially benefit clinical care and quality improvement initiatives.The PSS likely is useful for diagnosing children with suspected or confirmed infection transferred to a PICU.