Citation

Dickson JM, Wang X, St John AE, Lim EB, Stern SA, White NJ. Mil. Med. 2018; ePub(ePub): ePub.

Affiliation

Department of Emergency Medicine, University of Washington and Harborview Medical Center, Box 359702 325 9th Ave, Seattle, WA 98104.

Copyright

(Copyright © 2018, Association of Military Surgeons of the United States)

DOI

10.1093/milmed/usy001

PMID

29547998

Abstract

INTRODUCTION: Traumatic brain injury (TBI) and hemorrhagic shock (HS) are the leading causes of traumatic death worldwide and particularly on the battlefield. They are especially challenging when present simultaneously (polytrauma), and clear blood pressure end points during fluid resuscitation are not well described for this situation. The goal of this study is to evaluate for any benefit of increasing blood pressure using a vasopressor on brain blood flow during initial fluid resuscitation in a swine polytrauma model.

MATERIALS AND METHODS: We used a swine polytrauma model with simultaneous TBI, femur fracture, and HS with uncontrolled noncompressible internal bleeding from an aortic tear injury. Five animals were assigned to each of three experimental groups (hydroxyethyl starch only [HES], HES + 0.4 U/kg vasopressin, and no fluid resuscitation [No Fluids]). Fluids were given as two 10 mL/kg boluses according to tactical field care guidelines. Primary outcomes were mean arterial blood pressure (MAP) and brain blood flow at 60 min. Secondary outcomes were blood flows in the heart, intestine, and kidney; arterial blood lactate level; and survival at 6 hr. Organ blood flow was measured using injection of colored microspheres.

RESULTS: Five animals were tested in each of the three groups. There was a statistically significant increase in MAP with vasopressin compared with other experimental groups, but no significant increase in brain blood flow during the first 60 min of resuscitation. The vasopressin group also exhibited greater total internal hemorrhage volume and rate. There was no difference in survival at 6 hours.

CONCLUSION: In this experimental swine polytrauma model, increasing blood pressure with vasopressin did not improve brain perfusion, likely due to increased internal hemorrhage. Effective hemostasis should remain the top priority for field treatment of the polytrauma casualty with TBI.

Language: en