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

Area of Science:

• Trauma Resuscitation
• Hemodynamic Monitoring
• Clinical Outcomes Research

Background:

• Initial systolic blood pressure (SBP1) <110 mmHg predicts mortality but may not capture dynamic hemodynamic changes during resuscitation.
• The prognostic value of subsequent blood pressure measurements in trauma is not fully established.

Purpose of the Study:

• To evaluate the additional prognostic value of the second recorded systolic blood pressure (SBP2) and the change in systolic blood pressure (ΔSBP) in trauma patients.
• To determine if SBP2 and ΔSBP improve prediction of inhospital mortality and need for blood transfusion.

Main Methods:

• Retrospective chart review of 8,798 trauma activations over 8 years.
• Analysis of initial (SBP1) and second (SBP2) systolic blood pressures, and their difference (ΔSBP = SBP2 - SBP1).
• Logistic regression models used to assess the association of SBP2 and ΔSBP with inhospital mortality and early blood transfusion, with model fit assessed by likelihood ratio test and AIC.

Main Results:

• 12% had SBP1 <110 mmHg and 13% had SBP2 <110 mmHg; 5% died and 4% received ≥2 units of blood within 4 hours.
• Addition of ΔSBP significantly improved the model fit for predicting both mortality and blood transfusion.
• ΔSBP improved prediction for penetrating injuries and high Injury Severity Scores (≥9), but not for blunt traumatic brain injuries.

Conclusions:

• The second systolic blood pressure (SBP2) and the change (ΔSBP) provide significant additional prognostic information in trauma care.
• Monitoring subsequent hemodynamic data beyond the initial blood pressure is crucial for improving trauma outcome prediction.
• Consideration should be given to incorporating ΔSBP into trauma databases for enhanced prognostic capabilities.