Do Intravenous Gas Bubbles Formed from Blood Products Infuse in the Aeromedical Evacuation Environment Influence Outcomes in Traumatic Brain Injuries (TBI)

Abstract

Background: The combined injury of traumatic brain injury (TBI)/hemorrhagic shock has been shown to worsen coagulopathy/systemicinflammation thereby increasing post-traumatic morbidity/mortality. Aeromedical evacuation (AE) to definitive care may exacerbate postinjury morbidity due to inherent hypobaric hypoxic environment. We hypothesized that blood product resuscitation may mitigate adversephysiologic effects of flight post-injury. Methods: An established porcine model of controlled cortical injury was used to induce TBI.Intracerebral monitors were placed to record intracranial pressure (ICP), brain tissue oxygenation, and cerebral perfusion. Each of the 42models were bled while under general anesthesia to a goal mean arterial pressure of 40 +/- 5 mmHg for 1 hour. Models were grouped according to resuscitation strategy utilized - Lactated Ringers (LR) or shed whole blood (WB) - then placed into an altitude chamber for 2 hours at ground, 8,000ft, or 22,000ft, and observed for 4 hours. Hourly blood samples were analyzed for pro-inflammatory cytokines and lactate. Internal jugular vein blood flow was monitored continuously for microbubble formation with altitude changes. Results: Cerebral perfusion, tissue oxygenation, and ICP were unchanged among the 6 groups. No internal jugular venous microbubbles were observed with differing altitude or resuscitation strategy. Serum lactate levels from hour-2 of flight to the end of the 4-hour observation were significantly elevated in 22,000+LR compared to both 8,000+LR and 22,000+WB. Serum IL-6 levels were significantly elevated in 22,000+LR compared to22,000+WB, 8,000+LR and ground+LR hour-1 of observation. Serum TNF-alpha was significantly elevated hour-2 of flight in 8,000+LR vsground+LR, and 22,000+LR vs 22,000+WB hour-1 observation. Serum IL-1beta levels were significantly elevated hour-1 flight between8,000+LR and ground+LR.

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Document Details

Document Type
Technical Report
Publication Date
May 28, 2021
Accession Number
AD1148303

Entities

People

  • Kathleen E. Singer
  • Mackenzie C. Morris
  • Michael D Goodman
  • Richard Strilka
  • Sabre M. Stevens-topie
  • Taylor E. Wallen
  • Thomas C Blakeman

Organizations

  • United States Air Force School of Aerospace Medicine
  • University of Cincinnati

Tags

DTIC Thesaurus Topics

  • Acid-Base Imbalance
  • Aeromedical Evacuation
  • Air Force
  • Air Force Research Laboratories
  • Altitude
  • Altitude Chambers
  • Anesthesia
  • Blood
  • Brain Injuries
  • Cardiovascular Physiological Phenomena
  • Cardiovascular System
  • Casualties
  • Cerebral Hypoxia
  • Department Of Defense
  • Detection
  • Evacuation
  • Governments
  • Hemorrhage
  • Hemorrhagic Shock
  • Jugular Vein
  • Laboratory Animals
  • Medical Evacuation
  • Oxygenation
  • Proteins
  • Veins

Fields of Study

  • Medicine

Readers

  • Neurotrauma and Rehabilitation Medicine.
  • Trauma Surgery or Emergency Medicine.
  • Underwater engineering and Marine Technology.