Empirically Derived Age-Based Vital Signs for Children in the Out-of-Hospital Setting

To compare Pediatric Advanced Life Support (PALS) vital signs criteria to empirically derived vital signs cut-points for predicting out-of-hospital interventions in children.

We performed a cross-sectional study of pediatric encounters (<18 years) using the 2019 to 2020 datasets of the National Emergency Medical Services Information System, which we randomly divided into equal size derivation and validation samples. We developed age-based centile curves for initial heart rate, respiratory rate, and systolic blood pressure using generalized additive models for location, scale, and shape, which we evaluated in the validation sample. In addition, we compared the proportion of encounters with at least 1 abnormal vital sign when using empirically derived and PALS criteria and calculated their associations with the delivery of out-of-hospital medical interventions (eg, vascular access, medication delivery, or airway maneuvers).

We included 3,704,398 encounters. Among encounters with all 3 vital signs recorded (n=2,595,217), 45.9% had at least 1 abnormal vital sign using empirically derived criteria and 75.6% with PALS derived criteria. A higher proportion of encounters with a heart rate, respiratory rate, or systolic blood pressure less than 10th or more than 90th age-based empirically derived percentile had medical interventions than those with abnormal vital signs using PALS criteria.

PALS criteria classified a high proportion of children as having abnormal vital signs. Empirically derived vital signs developed from out-of-hospital encounters more accurately predict the delivery of the out-of-hospital medical interventions. If externally validated and correlated to inhospital outcomes, these cut-points may provide a useful assessment tool for children in the out-of-hospital setting.