Antibiotic regimen optimization for severe exsanguination in a live swine model

Sepsis is a significant contributor to mortality for trauma patients beyond 48 hours from their initial trauma, in addition to being a major source of morbidity in the elective surgery population. Prophylactic antibiotics are recommended for patients presenting with penetrating trauma due to this risk. Current guidelines do not provide definitive recommendations on redosing for patients requiring blood transfusions. We sought to characterize the bioavailability of prophylactic antibiotics in the setting of severe hemorrhage and whole-blood resuscitation in a swine model.

Sus Scrofa swine underwent a controlled hemorrhage and whole-blood resuscitation protocol following the administration of weight-based vancomycin. Control animals did not undergo hemorrhage or transfusion. Experimental animals underwent a controlled hemorrhage followed by a whole-blood resuscitation starting at 2 units and increasing to 10 units in 2-unit increments. Serum vancomycin levels were collected at regular time intervals over a 4-hour period.

There was a shorter time to reach subtherapeutic serum vancomycin levels within the 4, 6, 8, and 10-unit arms compared with the control arm. There was a significant decrease in serum vancomycin level immediately following the hemorrhage and transfusion in the 4, 6, 8, and 10-unit arms when compared with similar time intervals from vancomycin infusion of the control arm.

Prophylactic vancomycin dosing was subtherapeutic after four units of whole-blood resuscitation for massive hemorrhage in our swine model. Redosing at more frequent intervals may be considered for patients who have more than four to six units of hemorrhage. (J Trauma Acute Care Surg. 2026;100:929-935. Copyright © 2026 Wolters Kluwer Health, Inc. All rights reserved.).

Prognostic; Level II.