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Background

Effective handoffs of care are critical for maintaining patient safety and avoiding communication problems. Using the flow disruption observation technique, we examined transitions of care along the trauma pathway. We hypothesized that more transitions would lead to more disruptions, and that different pathways would have different numbers of disruptions.

Methods

We trained observers to identify flow disruptions, and then followed 181 patients from arrival in the emergency department (ED) to the completion of care using a specially formatted PC tablet. We mapped each patient’s journey and recorded and classified flow disruptions during transition periods into seven categories.

Results

Mapping the transitions of care shows that approximately four of five patients were assessed in the ED, transferred to imaging for further diagnostics, and then returned to the ED. There was a mean of 2.2 ± 0.09 transitions per patient, a mean of 0.66 ± 0.15 flow disruptions per patient, and 0.31 ± 0.07 flow disruptions per transition. Most of these (53%) were related to coordination problems. Although disruptions did not rise with more transitions, patients who went directly to the operating room or needed direct admission to intensive care unit were significantly more likely (P = 0.0028) to experience flow disruptions than those who took other, less expedited pathways.

Conclusions

Transitions in trauma care are vulnerable to systems problems and human errors. Coordination problems predominate as the cause. Sicker, time-pressured, and more at-risk patients are more likely to experience problems. Safety practices used in motor racing and other industries might be applied to address these problems.  相似文献   
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The goal of the Air Force Nursing Research Program at WHMC is to conduct research on topics unique to Air Force and military nursing. The nine stressors of flight and the military environment of care have been used as a conceptual model to guide the development of research studies. The studies conducted to date describe how the environment affects practice and when the environment directly affects the patient. The studies conducted are examples of the numerous military nursing research projects supported by funding from the TSNRP. The research funded by TSNRP contributes to the body of nursing knowledge by supporting scientific research, particularly knowledge that is unique to the military. As our nation faces the threat of chemical and biologic attacks, terrorism, and increased deployment of soldiers to battlefields in remote locations throughout the world, it is more important than ever that we ensure the advancement of military nursing research. Supporting research that advances healthcare in peace and in war is critical to the care of our military members and their families. This will require that research funds continue to be available to support military nursing research, that a strong infrastructure to provide resources in support of nursing research programs continues to exist, and that the military nursing corps continues to attract, train, and retain PhD prepared nurse researchers. Given the results of the research completed to date, the following evidence-based practice can be applied to the care of the patient described at the beginning of this article: The nurse positions the patient in the center of the cargo compartment, away from the bulkhead, toward the front of the aircraft, the warmest location during flight. While enroute, the patient will need to be positioned on an aerovac mattress, repositioned frequently, and have his/her heels elevated at all times. Additional padding may be needed for areas adjacent to the litter cross members to reduce pressure on the skin in areas prone to pressure ulcer formation. Should the patient need endotracheal suctioning, the nurse knows that hyperoxygenation-hyperinflation is effective in preventing suctioning-induced hypoxemia. In addition, the suction pressure will need to be increased to account for the effects of altitude without exceeding the pressure limits on the transport ventilator and causing catastrophic ventilator failure. Because there is not enough room on the litter for the chest tube drainage tubing to lay straight, it will be coiled and should dependent loops develop, they should be drained every 15 minutes. This is Air Force nursing research in practice.  相似文献   
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OBJECTIVE: Acute renal failure remains a major challenge in critical care medicine. Both neutrophils and chemokines have been proposed as key components in the development of acute renal failure. Although the Duffy antigen receptor for chemokines (DARC) is present in several tissues and a highly specific ligand for various chemokines, its exact role in vivo remains unclear. DESIGN: Prospective, controlled experimental study. SETTING: University-based research laboratory. SUBJECTS: C57BL/6 wild-type and DARC gene-deficient mice (DARC-/-). INTERVENTIONS: To unravel the functional relevance of DARC in vivo, we compared wild-type and DARC-/- using neutrophil-dependent models of acute renal failure, induced by either local (renal ischemia-reperfusion) or systemic (endotoxemia, lipopolysaccharide) injury. MEASUREMENTS AND MAIN RESULTS: Plasma creatinine and blood urea nitrogen concentrations served as indicators of renal function or dysfunction. Enzyme-linked immunosorbent assays were used to measure tissue and plasma chemokine concentrations. We also performed immunostaining to localize chemokine expression and flow cytometry to evaluate neutrophil recruitment into the kidney. Following renal injury, wild-type mice developed moderate renal ischemia-reperfusion(lipopolysaccharide, 300% increase in plasma creatinine concentrations) to severe acute renal failure (renal ischemia-reperfusion, 40% mortality) as well as extensive renal neutrophil recruitment. DARC-/- mice exhibited no renal dysfunction (renal ischemia-reperfusion) or only very mild renal dysfunction (lipopolysaccharide, 20% increase in serum creatinine concentrations). DARC-/- mice showed no postischemic neutrophil infiltration. Although DARC-/- and wild-type mice exhibited similar global renal neutrophil-recruitment during endotoxemia, DARC-/- mice showed significantly impaired neutrophil extravasation. Total renal concentrations of the chemokine macrophage inflammatory protein 2, which has been shown to bind to DARC and to be crucial in postischemic acute renal failure, were either identical (lipopolysaccharide) or only moderately different (renal ischemia-reperfusion) between wild-type and DARC-/- mice. Immunostaining revealed an absence of macrophage inflammatory protein-2 in renal endothelial cells of DARC-/- mice. CONCLUSIONS: We suggest that DARC predominantly exerts its effects by controlling spatial chemokine distribution, which in turn regulates neutrophil recruitment and subsequent acute renal failure.  相似文献   
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Interaction of the T cell receptor (TCR) with peptide/major histocompatibility complexes (MHC) in the thymus is of critical importance for developing thymocytes. In a previous study, we described an antagonist peptide that inhibited negative selection of transgenic thymocytes induced by an agonist peptide. In this study we show that this antagonist peptide can induce positive selection of CD8+ thymocytes more efficiently than the agonist or the weak agonist peptides, whereas the opposite is true for their ability to cause negative selection. The intracellular signals induced in thymocytes by such peptides after TCR ligation was examined in CD4+8+ double-positive thymocytes from F5/β2mo/Rag-1o transgenic mice. TCR ligation with either the agonist, weak agonist, or antagonist peptide variants resulted in hyperphosphorylation of CD3ζ, CD3, ZAP-70, Syk, Vav, SLP-76, and pp36–38. The extent of phosphorylation of these intracellular proteins correlated with the efficiency with which the peptide analogs induced apoptosis of immature thymocytes. Unexpectedly, there was no correlation between the upstream TCR signaling pathways analyzed and the capacity of the different peptides to induce positive selection.  相似文献   
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Hoang  T; Haman  A; Goncalves  O; Wong  GG; Clark  SC 《Blood》1988,72(2):823-826
The effects of recombinant interleukin-6 (IL-6) on the proliferation of blast precursors present in the peripheral blood of patients with acute myeloblastic leukemia (AML) was investigated. IL-6 had little effect by itself; however, it synergized with granulocyte macrophage colony- stimulating factor (GM-CSF) and interleukin-3 (IL-3) in the stimulation of AML blast colony formation. Responsiveness of blast progenitors to IL-6 was heterogeneous. On normal bone marrow cells the same synergy was observed on granulocyte and monocyte precursors (GM-CFC), while there was no significant effect on erythroid and multipotential precursors.  相似文献   
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