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Background: Combination of traumatic brain injury (TBI) and hemorrhagic shock (HS) can result in significant morbidity and mortality. We have previously shown that early administration of fresh frozen plasma (FFP) in a large animal model of TBI and HS reduces the size of the brain lesion as well as the associated edema. However, FFP is a perishable product that is not well suited for use in the austere prehospital settings. In this study, we tested whether a shelf-stable, low-volume, lyophilized plasma (LSP) product was as effective as FFP., Methods: Yorkshire swine (42-50 kg) were instrumented to measure hemodynamic parameters, intracranial pressure, and brain tissue oxygenation. A prototype, computerized, cortical impact device was used to create TBI through a 20-mm craniotomy: 15-mm cylindrical tip impactor at 4 m/s velocity, 100-millisecond dwell time, and 12-mm penetration depth. Volume-controlled hemorrhage was induced (40-45% total blood volume) concurrent with the TBI. After 2 hours of shock, animals were treated with (1) normal saline (NS, n = 5), (2) FFP (n = 5), and (3) LSP (n = 5). The volume of FFP and LSP matched the shed blood volume, whereas NS was 3 times the volume. Six hours after resuscitation, brains were sectioned and stained with TTC (2, 3, 5-Triphenyltetrazolium chloride), and lesion size (mm) and swelling (percent change in volume compared with the contralateral, uninjured side) were measured., Results: This protocol resulted in a highly reproducible brain injury, with clinically relevant changes in blood pressure, cardiac output, tissue hypoperfusion, intracranial pressure, and brain tissue oxygenation. Compared with NS, treatment with LSP significantly (p < 0.05) decreased brain lesion size and swelling (51% and 54%, respectively)., Conclusion: In a clinically realistic combined TBI + HS model, early administration of plasma products decreases brain lesion size and edema. LSP is as effective as FFP, while offering many logistic advantages.

Background: We have previously shown that the extent of traumatic brain injury (TBI) in large animal models can be reduced with early infusion of fresh frozen plasma (FFP), but the precise mechanisms remain unclear. In this study, we investigated whether resuscitation with FFP or normal saline differed in their effects on cerebral metabolism and excitotoxic secondary brain injury in a model of polytrauma, TBI, and hemorrhagic shock., Methods: Yorkshire swine (n = 10) underwent Grade III liver injury, rib fracture, standardized TBI, and volume-controlled hemorrhage, (40% ± 5%) and were randomly resuscitated with either FFP or normal saline. Hemodynamic parameters and brain oxygenation were continuously monitored, while microdialysis was used to measure the brain concentrations of pyruvate, lactate, glutamate, and glycerol at baseline; 1 hour and 2 hours after shock; immediate postresuscitation (PR); as well as 2, 4, and 6 hours PR. Cells from the injured hemisphere were separated into mitochondrial and cytosolic fractions and analyzed for activity of the pyruvate dehydrogenase complex (PDH)., Results: There were no baseline differences in cerebral perfusion pressure, brain oxygenation, as well as concentrations of pyruvate, lactate, glutamate, and glycerol between the groups. At 2 hours and 4 hours PR, the FFP group had significantly higher cerebral perfusion pressures (52 [5] mm Hg vs. 43 [2] mm Hg, p = 0.016; and 50 [7] mm Hg vs. 37 [1] mm Hg, p = 0.008, respectively). There was a sustained and significant (p < 0.05) drop in the glutamate and glycerol levels in the FFP group, implying a decrease in excitotoxicity and brain damage, respectively. Mitochondrial PDH activity was significantly higher (2,666.2 [638.2] adjusted volume INT × mm vs. 1,293.4 [88.8] adjusted volume INT × mm, p = 0.008), and cytosolic PDH activity was correspondingly lower (671.4 [209.2] adjusted volume INT × mm vs. 3070.7 [484.3] adjusted volume INT × mm, p < 0.001) in the FFP group, suggesting an attenuation of mitochondrial dysfunction and permeability., Conclusion: In this model of TBI, polytrauma, and hemorrhage, FFP resuscitation confers neuroprotection by improving cerebral perfusion, diminishing glutamate-mediated excitotoxic secondary brain injury and reducing mitochondrial dysfunction.

Background: Heart rate complexity (HRC), commonly described as a "new vital sign," has shown promise in predicting injury severity, but its use in clinical practice has been precluded by the absence of real-time data. This study was conducted to evaluate the utility of real-time, automated, instantaneous, hand-held heart rate entropy analysis in predicting the need for lifesaving interventions (LSIs). We hypothesized that real-time HRC would predict LSIs., Methods: Prospective enrollment of patients who met criteria for trauma team activation was conducted at a Level I trauma center (September 2011 to February 2012). A novel, hand-held, portable device was used to measure HRC (by sample entropy) and time-domain heart rate variability continuously in real time for 2 hours after the moment of presentation. Electric impedance cardiography was used to determine cardiac output. Patients who received an LSI were compared with patients without any intervention (non-LSI). Multivariable analysis was performed to control for differences between the groups., Results: Of 82 patients enrolled, 21 (26%) received 67 LSIs within 24 hours of hospital arrival. Initial systolic blood pressure was similar in both groups. LSI patients had a lower Glasgow Coma Scale (GCS) score (9.2 [5.1] vs. 14.9 [0.2], p < 0.0001). The mean (SD) HRC value on presentation was 0.8 (0.6) in the LSI group compared with 1.5 (0.6) in the non-LSI group (p < 0.0001). With the use of logistic regression, initial HRC was the only significant predictor of LSI. A cutoff value for HRC of 1.1 yields sensitivity, specificity, negative predictive value, and positive predictive value of 86%, 74%, 94%, and 53%, respectively, with an accuracy of 77% for predicting an LSI., Conclusion: Decreased HRC on hospital arrival is an independent predictor of the need for LSI in trauma activation patients. Real-time HRC may be a useful adjunct to standard vital signs monitoring and predicts LSIs., Level of Evidence: Prognostic and diagnostic study, level III.

Background: Therapeutic angioembolization is a relatively new "rescue treatment" modality for gastrointestinal hemorrhage (GIH) for unstable patients who fail primary treatment approaches; however, the effectiveness of this treatment and the incidence of ischemic necrosis following embolization for acute GIH are poorly described. The purpose of this study was to evaluate the effectiveness and safety of "rescue" transcatheter superselective angioembolization (SSAE) for the treatment of hemodynamically unstable patients with GIH., Methods: A 10-year retrospective review of all hemodynamically unstable patients (systolic blood pressure < 90 mm Hg and ongoing transfusion requirement) who underwent "rescue" SSAE for GIH after failed endoscopic management was performed. All patients with evidence of active contrast extravasation were included. Data were collected on demographics, comorbidities, clinical presentation, and type of intravascular angioembolic agent used. Outcomes included technical success (cessation of extravasation), clinical success (no rebleeding requiring intervention within 30 days), and incidence of ischemic complications., Results: Ninety-eight patients underwent SSAE for GIH during the study period; 47 were excluded owing to lack of active contrast extravasation. Of the remaining 51 patients, 22 (43%) presented with a lower GIH and 29 (57%) with upper GIH. The majority underwent embolization with a permanent agent (71%), while the remaining patients received either a temporary agent (16%) or a combination (14%). The overall technical and clinical success rates were 98% and 71%, respectively. Of the 14 patients with technical success but clinical failure (rebleeding within 30 days) and the 1 patient with technical failure, 4 were managed successfully with reembolization, while 2 underwent successful endoscopic therapy, and 9 had surgical resections. Only one patient had an ischemic complication (small bowel necrosis) requiring resection., Conclusion: SSAE, with reembolization if necessary, is an effective rescue treatment modality for hemodynamically unstable patients with active GIH. Of the patients, 20% will fail SSAE and require additional intervention. Ischemic complications are extremely rare., Level of Evidence: Therapeutic study, level IV.

Background: Traumatic brain injury (TBI) and hemorrhage are the leading causes of trauma-related mortality. Both TBI and hemorrhage are associated with coagulation disturbances, including platelet dysfunction. We hypothesized that platelet dysfunction could be detected early after injury, and that this dysfunction would be associated with early activation, as measured by circulating levels of platelet activation markers., Methods: A total of 33 swine were allocated to TBI and hypotension (n = 27, TBI and volume-controlled 40% blood loss) or controls (n = 6, anesthesia and instrumentation only). Animals in the TBI/Hemorrhage group were left hypotensive, defined as mean arterial pressure of 35 mm Hg, for 2 hours. Blood samples were drawn at baseline and 3 minutes and 15 minutes following injury as well as following 2 hours of shock. Samples were analyzed for platelet aggregation using impedance aggregometry with agonists collagen, arachidonic acid, and adenosine diphosphate (ADP) and thromboelastography (TEG) and circulating levels of platelet activation markers transforming growth factor-β (TGF-β), CD40 ligand, and sP-selectin., Results: Platelet ADP aggregation was significantly lower in the TBI/Hemorrhage group when compared with the control group 15 minutes following injury (62.4 vs. 80.4 U, p = 0.03) as well as following 2 hours of hypotension (59.9 vs. 73.5 U, p < 0.01). The latter was associated with lower TEG measured clot strength (TEG-MA, 74.1 vs. 79.4 mm, p = 0.05). No difference in collagen or arachidonic acid aggregation was observed. TGF-β levels were significantly higher in the TBI/Hemorrhage group following 2 hours of hypotension (1,764 vs. 1,252 pg/mL, p = 0.01). No differences in CD40 ligand or sP-selectin levels were observed., Conclusion: In this combined model of TBI and hemorrhage, a significantly lower ADP-induced platelet aggregation was detected 15 minutes following injury that was further aggravated during the 2-hour shock period. This dysfunction was associated with an increase in platelet activation marker TGF-β.