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Shallow-water Cretaceous, carbonate platform archives have only rarely been explored through their elemental signature. Yet, facies-sensitive geochemical records can shed light onto the specific dynamics of shallow/proximal settings, where changes in depositional conditions are pronounced. Changes stemming from early and later diagenetic processes must be considered, since they may alter the original geochemical signals, but still contribute to a better understanding of the evolution of ancient shallow carbonates. Here, the elemental record of a variety of carbonate materials from two middle Cenomanian coastal lagoon settings is examined. The two selected sections (Lousa and Lampas, W Portugal) provide a varied record of lithofacies, including matrix micrite, corresponding to diverse palaeoenvironments (marine, marine lagoon, restricted lagoon and subaerial exposed intervals), along with dolomitized beds and atypical darkened grey carbonate horizons. Sparry carbonate veinlets that intersect these materials are included for comparison. Based on the characteristic elemental composition of each carbonate material, and by means of a stepwise statistical approach, dolomitization was determined to be a rather early feature occurring exclusively along shallow to frequently exposed intervals. In contrast, carbonate veinlets were identified as the latest diagenetic event. Matrix micrite and darkened beds present the lowest degree of geochemical differentiation, though certain key elemental contrasts allow for their comparison. Accordingly, the atypical case of darkened beds was attributed to an early blackening process in which low contents of organic matter and non-carbonate mineral phases played a decisive role. Matrix micrite samples—presenting a rather narrow range of elemental fluctuations—were linked to previously identified palaeoenvironmental settings by means of stratigraphically constrained cluster analysis. Specific combinations of elemental trends identified for each established cluster reflect variations in palaeoclimatic regimes throughout the studied interval. Furthermore, the degree of connectivity between open waters and coastal lagoons emerged as predictive of the distribution of major and trace elements in ancient shallow carbonates. This study explores the depositional and diagenetic controls forcing elemental distribution across dynamic shallow carbonate settings, as is the case of coastal lagoons. Complex and atypical elemental fingerprints, established by means of statistical analysis, provide arguments to reconstruct the evolution of the examined carbonate materials. Our findings are highly pertinent, as they: (i) provide a rich dataset not only regarding Lusitanian Basin deposits, but also for coeval settings where basin evolution and diagenesis are pivotal; (ii) underline the insight to be gained from time series analyses of raw elemental data collected from carbonate facies; and (iii) place a suite of numerical analyses within a logical hierarchy for stratigraphic facies analysis, fully supported by independent data. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To identify predictive factors causing mortality in patients with injuries to the portal (PV) and superior mesenteric veins (SMV). Design: Retrospective analysis of prospectively collected data. Materials and methods: Adults admitted with blunt or penetrating PV and SMV injuries at an academic level I trauma center during a 20-year period. Results: Of 26,387 major trauma victims admitted from 1987 through 2006, 26 sustained PV or SMV injuries (PV=15, SMV=11). Mechanism of injury was penetrating in 19 (73%) and 20 were in shock. Active hemorrhage occurred in 21. Most patients had associated injuries (2.9±1.8/patient). Mean Injury Severity Score (ISS) was 27.8±16.8. All PV injuries underwent suture repair and 27% of SMV injuries were ligated. Overall mortality was 46% (PV=47%, SMV=45%). Stab wounds had a lower mortality (31%) compared to gunshot wounds (67%) and blunt injuries (57%). Nonsurvivors had a higher ISS (35.8 vs. 20.9; p =0.02), more associated injuries (3.7 vs. 2.2; p =0.02), were older, and had active hemorrhage. Active hemorrhage (p =0.04) was independently related to death while shock on admission (odds ratio=6.1, p =0.61) trended toward higher mortality. Conclusion: Despite improvements in trauma care, mortality of PV and SMV injuries remains high. Shock, active hemorrhage, and associated injuries were predictive of increased mortality. [Copyright &y& Elsevier]

Trauma has been perceived by the public as occurring as an isolated event, always resulting in favorable outcomes. There has therefore been a lack of discussion of futility of care and termination of care when dealing with the sick trauma patient. Several stages exist where issues of futility and early termination of care must be considered. These include the prehospital set- ting and involve the emergency medical service system in recognizing those patients who are nonsurvivors. Next is in the emergency room, where heroic measures may not benefit the very sick patient. In the operating room, the surgeon must always reassess and recognize when massive resuscitation will not benefit a particular trauma patient. Lastly, the intensivist must recognize those patients who may or may not benefit from continued efforts to sustain life. [ABSTRACT FROM AUTHOR]