UMEM Educational Pearls

Category: EMS

Title: Should there be a different set of vital sign "norms" for EMS?

Keywords: vital signs, age, pediatric, prehospital intervention (PubMed Search)

Posted: 2/21/2024 by Jenny Guyther, MD (Updated: 4/13/2024)
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Vital signs in children can be difficult to remember since they vary with age.  Using a standardized card or app (such as PALS) can help EMS clinicians remember the values.  Most pediatric vital sign reference ranges were derived from samples of healthy children in the outpatient setting (ie PALS).  This study attempted to validate a range of pediatric vital signs that were more accurate in predicting the need for prehospital interventions compared to the standard PALS vital sign ranges. The thought was that by using EMS data, these vital sign ranges could better alert EMS to patients in need of acute intervention.

The authors used a large EMS database to determine the vital signs for the patients age and correlated that to prehospital interventions (including IV, medication, EKG, advanced airway management, ect).  They used the <10% and >90% for the age values (termed "extreme" vitals signs) as a cut off to be considered abnormal.  Using the EMS derived values, 17.8% of the encounters with an extreme vital sign received medication.  If the PALS abnormal vital sign range was used, only 15.2% of those patients were given medications.  Overall, encounters with an extreme vital sign had a higher proportion of any intervention being performed compared to other vital sign criteria (i.e. only 33.7% with PALS).

These extreme vital signs also had a greater accuracy in predicting mortality.

Bottom line: While vital signs are based on physiology that does not change based on location, using a seperate criteria for the EMS population, can improve discrimination between sick and sicker patients and hopefully allow EMS to recognize and intervene on sicker patients sooner.


Ramgopal S, Sepanski RJ, Crowe RP, Martin-Gill C. External validation of empirically derived vital signs in children and comparison to other vital signs classification criteria [published online ahead of print, 2023 Apr 27]. Prehosp Emerg Care. 2023;1-15. doi:10.1080/10903127.2023.2206473