Efficacy and Safety of Prehospital Blood Transfusion in Traumatized Patients: A Systematic Review and Meta-Analysis

Background: Approximately five million individuals have traumatic injuries annually. Implementing prehospital blood-component transfusion (PHBT), encompassing packed red blood cells (p-RBCs), plasma, or platelets, facilitates early hemostatic volume replacement following trauma. The lack of uniform PHBT guidelines persists, relying on diverse parameters and physician experience.

Aim: This study aims to evaluate the efficacy of various components of PHBT, including p-RBCs and plasma, on mortality and hematologic-related outcomes in traumatic patients.

Methods: A comprehensive search strategy was executed to identify pertinent literature comparing the transfusion of p-RBCs, plasma, or a combination of both with standard resuscitation care in traumatized patients. Eligible studies underwent independent screening, and pertinent data were systematically extracted. The analysis employed pooled risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous variables, each accompanied by their respective 95% confidence intervals (CI).

Results: Forty studies were included in the qualitative analysis, while 26 of them were included in the quantitative analysis. Solely P-RBCs alone or combined with plasma showed no substantial effect on 24-hour or long-term mortality (RR = 1.13; 95% CI, 0.68 - 1.88; P = .63). Conversely, plasma transfusion alone exhibited a 28% reduction in 24-hour mortality with a RR of 0.72 (95% CI, 0.53 - 0.99; P = .04). In-hospital mortality and length of hospital stay were mostly unaffected by p-RBCs or p-RBCs plus plasma, except for a notable three-day reduction in length of hospital stay with p-RBCs alone (MD = -3.00; 95% CI, -5.01 to -0.99; P = .003). Hematological parameter analysis revealed nuanced effects, including a four-unit increase in RBC requirements with p-RBCs (MD = 3.95; 95% CI, 0.69 - 7.21; P = .02) and a substantial reduction in plasma requirements with plasma transfusion (MD = -0.73; 95% CI, -1.28 to -0.17; P = .01).

Conclusion: This study revealed that plasma transfusion alone was associated with a substantial decrease in 24-hour mortality. Meanwhile, p-RBCs alone or combined with plasma did not significantly impact 24-hour or long-term mortality. In-hospital mortality and length of hospital stay were generally unaffected by p-RBCs or p-RBCs plus plasma, except for a substantial reduction in length of hospital stay with p-RBCs alone.