Evaluation and management of blunt traumatic aortic injury: a practice management guideline from the Eastern Association for the Surgery of Trauma

BACKGROUND: Blunt traumatic aortic injury (BTAI) is the second most common cause of death in trauma patients. Eighty percent of patients with BTAI will die before reaching a trauma center. The issues of how to diagnose, treat, and manage BTAI were first addressed by the Eastern Association for the Surgery of Trauma (EAST) in the practice management guidelines on this topic published in 2000. Since that time, there have been advances in the management of BTAI. As a result, the EAST guidelines committee decided to develop updated guidelines for this topic using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework recently adopted by EAST. METHODS: A systematic review of the MEDLINE database using PubMed was performed. The search retrieved English language articles regarding BTAI from 1998 to 2013. Letters to the editor, case reports, book chapters, and review articles were excluded. Topics of investigation included imaging to diagnose BTAI, type of operative repair, and timing of operative repair. RESULTS: Sixty articles were identified. Of these, 51 articles were selected to construct the guidelines. CONCLUSION: There have been changes in practice since the publication of the previous guidelines in 2000. Computed tomography of the chest with intravenous contrast is strongly recommended to diagnose clinically significant BTAI. Endovascular repair is strongly recommended for patients without contraindications. Delayed repair of BTAI is suggested, with the stipulation that effective blood pressure control must be used in these patients.(AU)

Role of fibrinogen in massive injury.

Coagulation is a complex cascade whose intact functioning is essential in helping control hemorrhage after injury. While traditionally ascribed to the combined effects of acidosis, hypothermia, factor consumption and factor dilution, coagulopathy is also directly related to injury as well as hypofibrinogenemia and hyperfibrinolysis. Low fibrinogen concentration is readily determined with standard laboratory profiling, but direct analysis of hyperfibrinolysis relies on either thromboelastography or rotational thromboelastometry. Both conditions offer opportunities for therapeutic intervention, and inhibition or abrogation of hyperfibrinolysis in particular may significantly improve survival in patients with injury and massive hemorrhage. Herein, we explore the underpinnings of trauma associated coagulopathy, the basic science behind the role of fibrinogen in acute traumatic coagulopathy, and the rationale behind and the data derived from management of hypofibrinogenemia as well as hyperfibrinolysis.

Physical and biological regulation of proteoglycan turnover around chondrocytes in cartilage explants. Implications for tissue degradation and repair.

The development of clinical strategies for cartilage repair and inhibition of matrix degradation may be facilitated by a better understanding of (1) the chondrocyte phenotype in the context of a damaged extracellular matrix, and (2) the roles of biochemical and biomechanical pathways by which matrix metabolism is mediated. Using methods of quantitative autoradiography, we examined the cell-length scale patterns of proteoglycan deposition and turnover in the cell-associated matrices of chondrocytes in adult bovine and calf cartilage explants. Results highlight a rapid turnover in the pericellular matrix, which may indicate spatial organization of PG metabolic pools, and specific biomechanical roles for different matrix regions. Subsequent to injurious compression of calf explants, which resulted in grossly visible tissue cracks and caused a decrease in the number of viable chondrocytes within explants, cell-mediated matrix catabolic processes appeared to increase, resulting in apparently increased rates of proteoglycan turnover around active cells. Furthermore, the influences of cell-stimulatory factors such as IL-1 beta appeared to be delayed in their effects subsequent to injurious compression, suggesting interactions between biomechanical and biochemical pathways of PG degradation. These results may provide a useful reference point in the development of in vitro models for cartilage injury and disease, and hint at possible new approaches in the development of cartilage repair strategies.

Expansion of functional NK cells in multiple tissue compartments of mice treated with Flt3-ligand: implications for anti-cancer and anti-viral therapy.

The generation and activity of NK cells appear to be regulated by a particular set of cytokines. We examined the in vivo effects of recombinant human Flt3 ligand (Flt3-L), a recently cloned potent hemopoietic cytokine, on NK cell development in mice. Daily i.p. administration of Flt3-L consistently induced striking increases in both the absolute number and the total cytotoxic activity of mature nonactivated NK cells within various tissues. Dose- and time-dependent increases were observed in the bone marrow (approximately 2- and approximately 11-fold, respectively), thymus (approximately 2.8- and approximately 2.0-fold), blood (approximately 11- and approximately 15-fold), spleen (approximately 10- and approximately 9-fold), and liver (approximately 15- and approximately 39-fold). In addition, IL-2 induced a rapid increase in NK activity, NK cell proliferative responses, generation of lymphokine-activated killer activity, and development of activated adherent NK cells, which were all significantly increased by Flt3-L treatment. Thus, in addition to its recently reported capacity to stimulate dendritic cell production, Flt3-L has a prominent biologic role in NK cell generation in vivo. This is probably a result of selectively induced expansion of NK cell progenitors (pro-NK cells), because Flt3-L stimulates in vitro proliferation of pro-NK cells without affecting the cytotoxicity of mature NK cells. The results also indicate that either alone or in combination with a potent activator of NK cells, such as IL-2, Flt3-L could be used to markedly augment the number and activity of NK cells, especially in the liver. Flt3-L appears to have considerable potential for therapy of both cancer and viral infection.