The role of shock index as a predictor of multiple-trauma patients' pathways

Abstract

Objectives: This research was conducted with the aim of investigating the accuracy of the shock index (SI) in distinguishing which multiple-trauma patients should be admitted to an intensive care unit (ICU) after treatment in an emergency room (ER).

Background: The SI is an easily obtained indicator, as it corresponds to an arithmetic ratio between the two parameters that are always measured during the first-aid treatment of multiple-trauma patients: heart rate (HR) and systolic blood pressure (SBP). There are many studies examining the SI in the multiple-trauma patients as a possible predictor of the destination unit. The SI is evaluated both at the trauma scene (pre-hospital SI-pH) and in the emergency room (SI-ER).

Design and methods: An observational study with a retrospective approach was conducted on 158 adult patients with multiple trauma.

Results: The mean SI-pH and SI-ER values were higher in ICU patients than in-patients discharged or admitted to a normal ward, but the difference between these two patient groups was significant only for the SI-ER. Analysis of the receiver operating characteristic (ROC) curves confirmed that only the SI-ER is significant as a reliable indicator for ICU admission with a best cut-off of 1·05. However, a threshold value of 0·75 was still able to establish the correct type of destination for multiple-trauma patients, with a sensitivity of 57·3% and a specificity of 62·5%.

Conclusions: This research showed that the SI-pH and SI-ER values are correlated, but only the SI-ER has shown statistical significance in terms of distinguishing the type of destination of multiple-trauma patient (ICU, ordinary ward or discharge) after initial treatment in the ER.

Relevance to clinical practice: The results of this study suggest the possibility of using SI in multiple-trauma patients as a triage indicator to assess the patients' care complexity and to guide the choice of proper clinical paths.

Keywords: Intensive care unit; Multiple trauma; Shock index.