Pulse Pressure as an Early Warning of Hemorrhage in Trauma Patients

Hypotension based on low systolic blood pressure (SBP) is a well-documented indicator of ongoing blood loss. However, the utility of pulse pressure (PP) for detection of hemorrhage has not been well studied. The purpose of this study was to determine whether a narrowed PP in nonhypotensive patients is an independent predictor of critical administration threshold (CAT+) hemorrhage requiring surgical or endovascular control.

We performed a retrospective single-center study (January 2010 to October 2014), including trauma patients ≥16 years old with SBP ≥ 90 mmHg upon emergency department (ED) admission. We identified patients who were both CAT+ and required either surgical or interventional radiology for definitive hemorrhage control as the active hemorrhage (AH) group. Analyses were then performed to elucidate the association between PP and hemorrhage.

Of the total 18,015 patients identified, 283 (1.6%) met the criteria for clinically significant hemorrhage. Mean PP was significantly lower in the AH group compared with the non-AH group (39 ± 18 mmHg vs 53 ± 19 mmHg, p < 0.0001). Multivariate analysis revealed that narrowed initial ED PP is an independent predictor of AH (adjusted odds ratio [AOR] 0.975) along with age (AOR 1.01), penetrating mechanism (AOR 9.476), field SBP (AOR 0.985), ED heart rate (AOR 1.024), and Injury Severity Score (AOR 1.126). Cutoff analysis of PP values identified a significantly higher risk of AH at a PP cutoff of 55 mmHg (AOR 3.44, p = 0.005, AUC 0.955) in patients 61 years or older vs 40 mmHg (AOR 2.73, p < 0.0001, AUC 0.940) for patients 16 to 60 years old. The predicted probability of AH increases as PP narrows.

In patients who are nonhypotensive, a narrowed PP is an independent early predictor of active hemorrhage requiring blood product transfusion and intervention for hemorrhage control.