The critical threshold value of systolic blood pressure for aortic occlusion in trauma patients in profound hemorrhagic shock.

BACKGROUND: This study aimed to determine the critical threshold of systolic blood pressure (SBP) for aortic occlusion (AO) in severely injured patients with profound hemorrhagic shock. METHODS: All adult patients (>15 years) undergoing AO via resuscitative endovascular balloon occlusion of the aorta (REBOA) or thoracotomy with aortic cross clamping (TACC) between 2014 and 2018 at level I trauma center were included. Patients who required cardiopulmonary resuscitation in the prehospital setting were excluded. A logistic regression analysis based on mechanism of injury, age, Injury Severity Score, REBOA/TACC, and SBP on admission was done. RESULTS: A total of 107 patients underwent AO. In 57, TACC was performed, and in 50, REBOA was performed. Sixty patients who underwent AO developed traumatic cardiac arrest (TCA), and 47 did not (no TCA). Penetrating trauma was more prevalent in the TCA group (TCA, 90% vs. no TCA, 74%; p < 0.05) but did not modify 24-hour mortality (odds ratio, 0.51; 95% confidence interval, 0.13-2.00; p = 0.337). Overall, 24-hour mortality was 47% (50) and 52% (56) for 28-day mortality. When the SBP reached 60 mm Hg, the predicted mortality at 24 hours was more than 50% and a SBP lower than 70 mm Hg was also associated with an increased of probability of cardiac arrest. CONCLUSION: Systolic blood pressure of 60 mm Hg appears to be the optimal value upon which AO must be performed immediately to prevent the probability of death (>50%). However, values of SBP less than 70 mm Hg also increase the probability of cardiac arrest. LEVEL OF EVIDENCE: Therapeutic study, level IV.