Take Two: Second Systolic Blood Pressure Provides Prognostic Information in Trauma

An initial systolic blood pressure (SBP1) of <110 mmHg has been shown to predict mortality. However, SBP1 may not reflect hemodynamic changes during initial resuscitation. We aimed to determine if the second recorded blood pressure (SBP2) could provide additional prognostic value.

An 8-year retrospective chart review was performed including patients who underwent trauma activations at a single institution. The initial systolic blood pressure (SBP 1) and second systolic blood pressure (SBP 2) were analyzed. Difference between the first and second systolic blood pressure (ΔSBP) was defined as SBP2 - SBP1. The primary outcome was inhospital mortality, and the secondary outcome was receipt of ≥2 units of blood in the first 4 h of admission. Univariable analysis and logistic regression analysis were performed to assess the relationship of SBP2 and ΔSBP with the study outcomes. Regression model fit was assessed by the likelihood ratio test and Akaike information criterion.

Eight thousand seven hundred and ninety-eight patients were included with 12% and 13% presenting with SBP1 <110 mmHg and SBP2 <110 mmHg, respectively. Four hundred and six (5%) died and 327 (4%) received ≥2 units of blood in the first 4 h. The addition of ΔSBP to regression models improved model fit in explaining the primary and secondary outcomes. Subgroup analysis found that the addition of ΔSBP improved model fit for those with penetrating mechanism of injury and those with Injury Severity Score of ≥9, but not for those with blunt moderate or severe traumatic brain injury.

SBP2 offers additional prognostic value in predicting trauma outcomes. Incorporating subsequent hemodynamic data during resuscitation beyond the initial SBP in trauma databases should be considered.