Comparison of Prehospital Calculated Age-Adjusted Pediatric Shock Index (SIPA) to Those Calculated in the ED for Identifying Trauma Patients That Needed the Highest-Level Activation Based on Consensus Criteria

Abstract

Background: The shock index (SI) is defined as the ratio of the heart rate to systolic blood pressure and a pediatric age-adjusted SI (SIPA) is more specific than the standard adult cutoff of 0.9 in identifying the sickest children presenting to a trauma center.

Goal: To utilize prehospital vital signs to calculate the SIPA score and compare them to the SIPA calculated in the trauma bay to determine if they have the same validity in identifying critically ill children as determined by the consensus based standard criteria for trauma activation.

Methods: Retrospective study using a cohort of patients transferred by EMS to a free standing, urban, level one, pediatric trauma center aged 1 to 16 years inclusive, and seen between January 1, 2016 and December 31, 2017. Vital signs collected during the patch call from the EMS agency were used to calculate the EMS SIPA. The first set of vital signs collected in the trauma bay was used to calculate the ED SIPA. Patients were dichotomized to an elevated or non-elevated ED SIPA and an elevated or non-elevated EMS SIPA.

Results: Our cohort consisted of 2651 patients. 546 (20.6%) patients had an elevated EMS SIPA and 438 (16.5%) had an elevated ED SIPA. When compared to their non-elevated counterparts, EMS and ED SIPA were both able to identify patients who met consensus criteria in all areas except the need for IR intervention, and unstable spinal fracture/spinal cord injury. For these criteria, the ED SIPA was better than the EMS SIPA. Sensitivity and specificity analysis reveal poor sensitivity for both measures but a high specificity for ED and EMS SIPA. Both SI and SIPA have a poor PPV but high NPV.

Conclusions: This study utilized prehospital vital signs to calculate the SIPA score and compare them to the SIPA calculated in the trauma bay. Both scores had similar test metrics when based on the consensus based standard trauma criteria and could be utilized in the triage traumatic injuries.

Key words:

• pediatrics
• trauma
• shock