Effects of sequential aeromedical evacuations following traumatic brain injury in swine.

Introduction: Traumatic brain injuries (TBI) represent a significant percentage of critical injuries in military conflicts. Following injury, wounded warfighters are often subjected to multiple aeromedical evacuations (AE) and associated hypobaria, yet the impact in TBI patients remains to be characterized. This study evaluated the impact of two consecutive simulated AEs in a fluid-percussion TBI model in swine to characterize these effects.

Emulsion Effect on the Measurement of Standard Laboratory Blood Parameters.

Background: A number of pharmaceutical agents have limited water solubility and are therefore often prepared in a lipid emulsion. Emulsion renders plasma opaque and this could interfere with the accuracy of some standardized laboratory measurements, especially for optical or mechanical based assays. We determined the interference on some laboratory diagnostic values of blood specimens after propofol addition in vitro as well as in vivo when infused into swine.

Treatment of Swine Closed Head Injury with Perfluorocarbon NVX-428.

Pre-hospital treatment of traumatic brain injury (TBI) with co-existing polytrauma is complicated by requirements for intravenous fluid volume vs. hypotensive resuscitation. A low volume, small particle-size-oxygen-carrier perfluorocarbon emulsion NVX-428 (dodecafluoropentane emulsion; 2% / could improve brain tissue with minimal additional fluid volume.

Histopathological Evidence of Multiple Organ Damage After Simulated Aeromedical Evacuation in a Swine Acute Lung Injury Model.

Introduction: Rapid aeromedical evacuation (AE) is standard of care in current conflicts. However, not much is known about possible effects of hypobaric conditions. We investigated possible effects of hypobaria on organ damage in a swine model of acute lung injury.

Simulated Aeromedical Evacuation in a Polytrauma Rat Model.

Hemorrhage and traumatic brain injury can be lethal if left unattended. The transportation of severely wounded combat casualties from the battlefield to higher level of care via aeromedical evacuation (AE) may result in unintended complications. This could become a serious concern at the time of evacuation of mass casualties or for prolonged field care scenarios with limited resources.

Hypobaria during aeromedical evacuation exacerbates histopathological injury and modifies inflammatory response in rats exposed to blast overpressure injury.

Background: Aeromedical evacuation (AE) is often used as a rapid and effective way to evacuate patients. However, little is known about the possible effects of AE on patients with blast and traumatic brain injury. In the current study, we used blast overpressure (BOP) as a method to introduce traumatic brain injury in rats and investigated the effects of hypobaria during AE on histology and inflammatory response.

Effect of acute restraint stress in a polytrauma rat model.

Introduction: A stressful environment may contribute to poor outcomes after TBI. The current study evaluates the impact of acute stress in a polytrauma rat model.

Methods: Rats were stressed by a 45-minute immobilization period before instrumentation under ketamine (t1).

Brain oxygenation with a non-vasoactive perfluorocarbon emulsion in a rat model of traumatic brain injury.

Objective: The aim of this study was to assess, in two experiments, the safety and efficacy of the PFC emulsion Oxycyte as an oxygen therapeutic for TBI to test the hypothesis that early administration of this oxygen-carrying fluid post-TBI would improve brain tissue oxygenation (P O ).

Methods: The first experiment assessed the effects of Oxycyte on cerebral vasoactivity in healthy, uninjured rats using intravital microscopy. The second experiment investigated the effect of Oxycyte on cerebral P O using the PQM in TBI model.

Storage of nitroglycerin (NTG) admixed with HBOC-201 for 30 days in polyolefin plastic bags: a pilot study.

Hemorrhaged animals have benefited from resuscitation with the hemoglobin-based oxygen carrier (HBOC-201). Co-infusion of nitric oxide (NO) via separate intravascular lines is effective in attenuating HBOC-induced elevation of blood pressure. We tested whether nitroglycerin (NTG) and HBOC-201 can be packaged together as a single drug for resuscitation.

Do vented chest seals differ in efficacy? An experimental evaluation using a swine hemopneumothorax model.

Objective: Airways compromise was the second leading cause of potentially preventable death among combat casualties. We investigated the ability of five Food and Drug Administration-approved nonocclusive chest seals (CSs) to seal a bleeding chest wound and prevent tension hemopneumothorax (HPTX) in a swine model.

Methods: Following instrumentation, an open chest wound was created in the left thorax of spontaneously air-breathing anesthetized pigs (n = 26; 43 kg).

Cerebral Microvascular and Systemic Effects Following Intravenous Administration of the Perfluorocarbon Emulsion Perftoran.

Oxygen-carrying perfluorocarbon (PFC) fluids have the potential to increase tissue oxygenation during hypoxic states and to reduce ischemic cell death. Regulatory approval of oxygen therapeutics was halted due to concerns over vasoconstrictive side effects. The goal of this study was to assess the potential vasoactive properties of Perftoran by measuring brain pial arteriolar diameters in a healthy rat model.

The Emulsified PFC Oxycyte Improved Oxygen Content and Lung Injury Score in a Swine Model of Oleic Acid Lung Injury (OALI).

Purpose: Perfluorocarbons (PFCs) can transport 50 times more oxygen than human plasma. Their properties may be advantageous in preservation of tissue viability in oxygen-deprived states, such as in acute lung injury. We hypothesized that an intravenous dose of the PFC emulsion Oxycyte would improve tissue oxygenation and thereby mitigate the effects of acute lung injury.

Adherence evaluation of vented chest seals in a swine skin model.

Objectives: Perforation of the chest (open pneumothorax) with and without lung injury can cause air accumulation in the chest, positive intrapleural pressure and lead to tension pneumothorax if untreated. The performance of chest seals to prevent tension physiology depends partially on their ability to adhere to the skin and seal the chest wound. Novel non-occlusive vented chest seals were assessed for their adhesiveness on skin of live swine under normal and extreme environmental conditions to simulate austere battlefield conditions.

Sanguinate's effect on pial arterioles in healthy rats and cerebral oxygen tension after controlled cortical impact.

Sanguinate, a polyethylene glycol-conjugated carboxyhemoglobin, was investigated for cerebral vasoactivity in healthy male Sprague-Dawley rats (Study 1) and for its ability to increase brain tissue oxygen pressure (PbtO2) after controlled cortical impact (CCI) - traumatic brain injury (TBI) (Study 2). In both studies ketamine-acepromazine anesthetized rats were ventilated with 40% O2. In Study 1, a cranial window was used to measure the diameters of medium - (50-100μm) and small-sized (<50μm) pial arterioles before and after four serial infusions of Sanguinate (8mL/kg/h, cumulative 16mL/kg IV), volume-matched Hextend, or normal saline.

Infusion of solutions of pre-irradiated components in rats.

Introduction: The objective of this study was to conduct a 14-day toxicology assessment for intravenous solutions prepared from irradiated resuscitation fluid components and sterile water.

Methods: Healthy Sprague Dawley rats (7-10/group) were instrumented and randomized to receive one of the following Field IntraVenous Resuscitation (FIVR) or commercial fluids; Normal Saline (NS), Lactated Ringer's, 5% Dextrose in NS. Daily clinical observation, chemistry and hematology on days 1,7,14, and urinalysis on day 14 were evaluated for equivalence using a two sample t-test (p<0.

Determination of methemoglobin and hemoglobin levels in small volume samples.

Background/aims Hemoglobin-based oxygen carriers (HBOCs) have been previously studied as resuscitation fluids. Due to HBOCs specific molecular conformation, hemoglobin (Hb) and methemoglobin (MetHb) determination is not always possible with automated apparatus. A practical technique was designed that allows simultaneous reading of MetHb and Hb in small volume samples.

Endovascular Cooling Method for Hypothermia in Injured Swine.

We evaluated an endovascular cooling method to modulate core temperature in trauma swine models with and without fluid support. Anesthetized swine (N = 80) were uninjured (SHAM) or injured through a bone fracture plus soft tissue injury or an uncontrolled hemorrhage and then subdivided to target body temperatures of 38°C (normothermia) or 33°C (hypothermia) by using a Thermogard endovascular cooling device (Zoll Medical). Temperature regulation began simultaneously at onset of injury (T0).

In vitro alteration of hematological parameters and blood viscosity by the perfluorocarbon: Oxycyte.

Unlabelled: While perfluorocarbons (PFCs) may be useful in some clinical situations, previous studies have shown that interferences with chemistry analytes can occur with blood samples containing PFCs. This in vitro study focused on how the PFC Oxycyte may affect hematology measurements in blood samples. Swine blood diluted with Oxycyte or saline (Controls) were analyzed for Hemoglobin (Hb), Mean Corpuscular Volume (MCV),Hematocrit (Hct) and Fluorocrit (Fct) using a HemaVet, ABL-735 (ABL), or microhematocrit.

Perfluorocarbon NVX-108 increased cerebral oxygen tension after traumatic brain injury in rats.

Background: Hypoxia is a critical secondary injury mechanism in traumatic brain injury (TBI), and early intervention to alleviate post-TBI hypoxia may be beneficial. NVX-108, a dodecafluoropentane perfluorocarbon, was screened for its ability to increase brain tissue oxygen tension (PbtO2) when administered soon after TBI.

Methods: Ketamine-acepromazine anesthetized rats ventilated with 40% oxygen underwent moderate controlled cortical impact (CCI)-TBI at time 0 (T0).

The effect of the perfluorocarbon emulsion Oxycyte on platelet count and function in the treatment of decompression sickness in a swine model.

Decompression from elevated ambient pressure is associated with platelet activation and decreased platelet counts. Standard treatment for decompression sickness (DCS) is hyperbaric oxygen therapy. Intravenous perfluorocarbon (PFC) emulsion is a nonrecompressive therapy being examined that improves mortality in animal models of DCS.

Cerebral Vasoactivity and Oxygenation with Oxygen Carrier M101 in Rats.

The severity of traumatic brain injury (TBI) may be reduced if oxygen can be rapidly provided to the injured brain. This study evaluated if the oxygen-carrier M101 causes vasoconstricton of pial vasculature in healthy rats (Experiment 1) and if M101 improves brain tissue oxygen (PbtO) in rats with controlled cortical impact (CCI)-TBI (Experiment 2). M101 (12.

Effects of the Oxygen-Carrying Solution OxyVita C on the Cerebral Microcirculation and Systemic Blood Pressures in Healthy Rats.

The use of hemoglobin-based oxygen carriers (HBOC) as oxygen delivering therapies during hypoxic states has been hindered by vasoconstrictive side effects caused by depletion of nitric oxide (NO). OxyVita C is a promising oxygen-carrying solution that consists of a zero-linked hemoglobin polymer with a high molecular weight (~17 MDa). The large molecular weight is believed to prevent extravasation and limit NO scavenging and vasoconstriction.

Effects of perfluorocarbon dodecafluoropentane (NVX-108) on cerebral microvasculature in the healthy rat.

NVX-108, a dodecafluoropentane-based perfluorocarbon (PFC) emulsion, has therapeutic potential as an oxygen- carrying fluid for emergency medical treatment for traumatic brain injury (TBI) and hemorrhagic shock. Potential cerebral vasoactive properties were assessed by directly measuring pial arteriolar vessel diameters before and after a 30 minute intravenous (IV) infusion of 1.0 ml/kg (high dose [H]) or 0.

Use of recombinant factor VIIa (rFVIIa) as pre-hospital treatment in a swine model of fluid percussion traumatic brain injury.

Context: Recombinant factor VIIa (rFVIIa) has been used as an adjunctive therapy for acute post-traumatic hemorrhage and reversal of iatrogenic coagulopathy in trauma patients in the hospital setting. However, investigations regarding its potential use in pre-hospital management of traumatic brain injury (TBI) have not been conducted extensively.

Aims: In the present study, we investigated the physiology, hematology and histology effects of a single pre-hospital bolus injection of rFVIIa compared to current clinical practice of no pre-hospital intervention in a swine model of moderate fluid percussion TBI.