NIRS-derived muscle StO2 measurements perform similarly to BD in identifying poor perfusion and predicting the development of MODS or death after severe torso trauma, yet have the additional advantages of being continuous and noninvasive.

We investigate the thermal properties of the potential model equation of state of Akmal, Pandharipande and Ravenhall. This equation of state approximates the microscopic model calculations of Akmal and Pandharipande, which feature a neutral pion condensate. We treat the bulk homogeneous phase for isospin asymmetries ranging from symmetric nuclear matter to pure neutron matter and for temperatures and densities relevant for simulations of core-collapse supernovae, proto-neutron stars, and neutron star mergers. Numerical results of the state variables are compared with those of a typical Skyrme energy density functional with similar properties at nuclear densities, but which differs substantially at supra-nuclear densities. Analytical formulas, which are applicable to non-relativistic potential models such as the equations of state we are considering, are derived for all state variables and their thermodynamic derivatives. A highlight of our work is its focus on thermal response functions in the degenerate and non-degenerate situations, which allow checks of the numerical calculations for arbitrary degeneracy. These functions are sensitive to the density dependent effective masses of neutrons and protons, which determine the thermal properties in all regimes of degeneracy. We develop the "thermal asymmetry free energy" and establish its relation to the more commonly used nuclear symmetry energy. We also explore the role of the pion condensate at supra-nuclear densities and temperatures. Tables of matter properties as functions of baryon density, composition (i.e., proton fraction) and temperature are being produced which are suitable for use in astrophysical simulations of supernovae and neutron stars.Comment: 44 pages, 40 figures, 6 table

MT progresses rapidly to significant morbidity and mortality despite level I TC care. Patients who require MT can be predicted early, and persistent low StO2 identifies those MT patients destined to have poor outcome. The ultimate goal is to identify these high risk patients as early as possible to test new strategies to improve outcome. Further validation studies are needed to analyze appropriate allocation and study appropriate use of damage control interventions.

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Hypothesis: The diagnosis of acute respiratory distress syndrome (ARDS) carries significant additional morbidity and mortality among critically injured patients. Design: Retrospective case-control study using a prospectively maintained ARDS database. Setting: Surgical intensive care unit (ICU) in an academic county hospital. Patients: All trauma patients admitted to the ICU from January 1, 2000, to December 31, 2003, who developed ARDS as defined by (1) acute onset, (2) a partial pressure of arterial oxygen-fraction of inspired oxygen ratio of 200 or less, (3) bilateral pulmonary infiltrates on chest radiographs, and (4) absence of left-sided heart failure. Each patient with ARDS was matched with 2 control patients without ARDS on the basis of sex, age (±5 years), mechanism of injury (blunt or penetrating), Injury Severity Score (±3), and chest Abbreviated Injury Score (±1). Main Outcome Measures: Mortality, hospital charges, hospital and ICU lengths of stay, and complications (defined as pneumonia, deep venous thrombosis, pulmonary embolism, acute renal failure, and disseminated intravascular coagulopathy). Results: Of 2042 trauma ICU admissions, 216 patients (10.6%) met criteria for ARDS. We identified 432 similarly injured control patients. Compared with controls, trauma patients with ARDS had more complications (43.1% vs 9.5%), longer hospital (32.2 vs 17.9 days) and ICU (22.1 vs 8.4 days) lengths of stay, and higher hospital charges ($267 037 vs $136 680) (PϽ.01 for all), but mortality was similar (27.8% vs 25.0%, P=.48). Conclusion: Although ARDS is associated with increased morbidity, hospital and ICU length of stay, and costs, it does not increase overall mortality among critically ill trauma patients.

We explore the thermal properties of hot and dense matter using a model that reproduces the empirical properties of isospin symmetric and asymmetric bulk nuclear matter, optical model fits to nucleon-nucleus scattering data, heavy-ion flow data in the energy range 0.5-2 GeV/A, and the largest well-measured neutron star mass of 2 M . This model, which incorporates finite range interactions through a Yukawa-type, finite-range force, is contrasted with a conventional zero-range Skyrme model. Both models predict nearly identical zero-temperature properties at all densities and proton fractions, including the neutron star maximum mass, but differ in their predictions for heavy-ion flow data. We contrast their predictions of thermal properties, including their specific heats, and provide analytical formulas for the strongly degenerate and non-degenerate limits. We find significant differences in the results of the two models for quantities that depend on the density derivatives of nucleon effective masses. We show that a constant value for the ratio of the thermal components of pressure and energy density expressed as Γ th = 1 + (P th /ε th ), often used in simulations of proto-neutron stars and merging compact object binaries, fails to adequately describe results of either nuclear model. The region of greatest discrepancy extends from sub-saturation densities to a few times the saturation density of symmetric nuclear matter. Our results suggest alternate approximations for the thermal properties of dense matter that are more realistic.

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