Characterizing the gut microbiome in trauma: significant changes in microbial diversity occur early after severe injury.

Background: Recent studies have demonstrated the vital influence of commensal microbial communities on human health. The central role of the gut in the response to injury is well described; however, no prior studies have used culture-independent profiling techniques to characterize the gut microbiome after severe trauma. We hypothesized that in critically injured patients, the gut microbiome would undergo significant compositional changes in the first 72 hours after injury.

Exposing the bidirectional effects of alcohol on coagulation in trauma: Impaired clot formation and decreased fibrinolysis in rotational thromboelastometry.

Background: Alcohol has been associated with altered viscoelastic testing in trauma, indicative of impaired coagulation. Such alterations, however, show no correlation to coagulopathy-related outcomes. Other data suggest that alcohol may inhibit fibrinolysis.

Characterization of distinct coagulopathic phenotypes in injury: Pathway-specific drivers and implications for individualized treatment.

Background: International normalized ratio (INR) and partial thromboplastin time (PTT) are used interchangeably to diagnose acute traumatic coagulopathy but reflect disparate activation pathways. In this study, we identified injury/patient characteristics and coagulation factors that drive contact pathway, tissue factor pathway (TF), and common pathway dysfunction by examining injured patients with discordant coagulopathies. We hypothesized that patients with INR/PTT discordance reflect differing phenotypes representing contact versus tissue factor pathway perturbations and that characterization will provide targets to guide individualized resuscitation.

Correlation between factor (F)XIa, FIXa and tissue factor and trauma severity.

Background: It has been observed that trauma patients often display elevated procoagulant activity that could be caused, in part, by tissue factor (TF). We previously observed that trauma patients with thermal, blunt, and penetrating injuries have active FIXa and FXIa in their plasma. In the current study, we evaluated the effect of injury severity, with or without accompanying shock, on the frequency and concentration of TF, FIXa, and FXIa in plasma from trauma patients.

The acute respiratory distress syndrome following isolated severe traumatic brain injury.

Background: Acute respiratory distress syndrome (ARDS) is common after traumatic brain injury (TBI) and is associated with worse neurologic outcomes and longer hospitalization. However, the incidence and associated causes of ARDS in isolated TBI have not been well studied.

Methods: We performed a subgroup analysis of 210 consecutive patients with isolated severe TBI enrolled in a prospective observational cohort at a Level 1 trauma center between 2005 and 2014.

Discovering the truth about life after discharge: Long-term trauma-related mortality.

Background: Outcome after traumatic injury has typically been limited to the determination at time of discharge or brief follow-up. This study investigates the natural history of long-term survival after trauma.

Methods: All highest-level activation patients prospectively enrolled in an ongoing cohort study from 2005 to 2012 were selected.

The Massive Transfusion Score as a decision aid for resuscitation: Learning when to turn the massive transfusion protocol on and off.

Background: Previous work proposed a Massive Transfusion Score (MTS) calculated from values obtained in the emergency department to predict likelihood of massive transfusion (MT). We hypothesized the MTS could be used at Hour 6 to differentiate who continues to require balanced resuscitation in Hours 7 to 24 and to predict death at 28 days.

Methods: We prospectively enrolled patients in whom the MT protocol was initiated from 2005 to 2011.

The found down patient: A Western Trauma Association multicenter study.

Background: Unconscious patients who present after being "found down" represent a unique triage challenge. These patients are selected for either trauma or medical evaluation based on limited information and have been shown in a single-center study to have significant occult injuries and/or missed medical diagnoses. We sought to further characterize this population in a multicenter study and to identify predictors of mistriage.

Beyond emergency surgery: redefining acute care surgery.

Background: Considerable debate exists regarding the definition, skill set, and training requirements for the new specialty of acute care surgery (ACS). We hypothesized that a patient subset could be identified that requires a level of care beyond general surgical training and justifies creation of this new specialty.

Materials And Methods: Reviewed patient admissions over 1-y to the only general surgical service at a level I trauma center-staffed by trauma and/or critical care trained physicians.

Differences in degree, differences in kind: characterizing lung injury in trauma.

Background: Acute lung injury following trauma remains a significant source of morbidity and mortality. Although multiple trauma studies have used hypoxemia without radiographic adjudication as a surrogate for identifying adult respiratory distress syndrome (ARDS) cases, the differences between patients with hypoxemia alone and those with radiographically confirmed ARDS are not well described in the literature. We hypothesized that nonhypoxemic, hypoxemic, and ARDS patients represent distinct groups with unique characteristics and predictors.

The effects of alcohol on coagulation in trauma patients: interpreting thrombelastography with caution.

Background: The effects of alcohol on coagulation after trauma remain unclear. In vitro studies show that alcohol may decrease clot strength and inhibit fibrinolysis. Observational data indicate that alcohol leads to altered thrombelastography (TEG) parameters indicative of impaired clot formation.

The whole is greater than the sum of its parts: hemostatic profiles of whole blood variants.

Background: Mounting evidence highlighting the benefits of hemostatic resuscitation has led to a renewed interest in whole blood (WB) and reconstituted WB (RWB). However, few data exist to characterize the clotting profiles of these variants. This study characterizes banked WB variants and RWB in standard 1:1:1 and 2:1:1 transfusion ratios of packed red blood cells, fresh frozen plasma, and platelets (PLTs).

The natural history and effect of resuscitation ratio on coagulation after trauma: a prospective cohort study.

Objective: To investigate the natural history of coagulation factor perturbation after injury and identify longitudinal differences in clotting factor repletion by red blood cell:fresh frozen plasma (RBC:FFP) transfusion ratio.

Background: Hemostatic transfusion ratios of RBC to FFP approaching 1:1 are associated with a survival advantage in traumatic hemorrhage, even in patients with normal coagulation studies.

Methods: Plasma was prospectively collected from 336 trauma patients during their intensive care unit stay for up to 72 hours from February, 2005, to October, 2011.

Cause and timing of death in massively transfused trauma patients.

Background: The purpose of this study was to characterize the cause of death in severely injured trauma patients to define potential responses to resuscitation.

Methods: Prospective analysis of 190 critically injured patients who underwent massive transfusion protocol (MTP) activation or received massive transfusion (>10 U of packed red blood cells [RBC] per 24 hours). Cause of death was adjudicated into one of four categories as follows: (1) exsanguination, (2) early physiologic collapse, (3) late physiologic collapse, and (4) nonsurvivable injury.

A paradigm shift in trauma resuscitation: evaluation of evolving massive transfusion practices.

Importance: The evolution of damage control strategies has led to significant changes in the use of resuscitation after traumatic injury.

Objective: To evaluate changes in the administration of fluids and blood products, hypothesizing that a reduction in crystalloid volume and a reduced red blood cell (RBC) to fresh frozen plasma (FFP) ratio over the last 7 years would correlate with better resuscitation outcomes.

Design: Observational prospective cohort study.

Criteria for empiric treatment of hyperfibrinolysis after trauma.

Background: Recent studies identify a survival benefit from the administration of antifibrinolytic agents in patients with severe injury and trauma. However, identification of hyperfibrinolysis requires thromboelastography, which is not widely available. We hypothesized that analysis of patients with thromboelastography-diagnosed hyperfibrinolysis would identify clinical criteria for empiric antifibrinolytic treatment in the absence of thromboelastography.

Characterization of platelet dysfunction after trauma.

Background: The increased morbidity and mortality associated with coagulopathy and thrombocytopenia after trauma are well described. However, few studies have assessed platelet function after injury.

Methods: Blood samples were prospectively collected from 101 patients with critical injury and trauma on arrival to the emergency department and serially after admission to a Level I urban trauma intensive care unit from November 2010 to October 2011 and functionally assayed for responsiveness to adenosine diphosphate, thrombin receptor-activating peptide, arachidonic acid (AA), and collagen using multiple electrode impedance aggregometry.