Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

The southern Apennine Arc

The Southern Apennine Arc (SAA), stretching from Central Apennines to Sicily, is the southern Italian part of the Apennine-Maghrebian chain, important segment of the circum-Mediterranean Alpidic tem. It is a complex arcuate thrust belt, composed by minor arcs of different size and curvature, with general convexity and vergency towards the Adria-Apulia-Africa foreland. Like the other parts of the Apennine chain, the SAA developed through the deformation of two major palaeogeographic domains. The first one, internal, is of oceanic type and is represented by Upper Jurassic to Oligocene tectono-sedimentary successions of the Liguria-Piedmont Ocean, linked to the Neo-Tethyan sea. The second one, external, is represented by Triassic to lower Miocene sedimentary sequences deposited on deformed continental crust along the Adria-Apulia-Africa passive margin, and is featured by an extensive carbonate platform/basin system. The two main units represented contiguous palaeogeographic domains up to the end of Mesozoic. They were then progressively incorporated into the chain. The SAA fold-and-thrust belt developed from Late Cretaceous to early Pleistocene at the subduction-collisional boundary between the European and the westward subducted Ionian and Adria plates. Large parts of the Mesozoic oceanic crust were subducted during an Alpine phase from Late Cretaceous to Eocene, while the continental collision of the European margin against the Adria-Apulia-Africa margin probably occurred between late Oligocene and Langhian-Serravallian. The chain was built as an accretionary wedge over a sinking and roll-backing slab, which forced the opening of the Tyrrhenian back-arc basin. The frontal arcs of the SAA overthrust now the Miocene-lower Pliocene, prevailingly terrigenous sequence of the most recent and external foredeep (“Adriatic foredeep”) and the scarcely deformed margin of the Apulian foreland, while the stack of thrust sheets of the Maghrebian Sicily are verging toward the southern Hyblean foreland. The SAA appears composed of two main wings, Central-Southern Apennines to the North, and Sicily to the South, with the Kabylo-Calabride Arc as hinge. Mesozoic-Tertiary platform carbonates, and marly/siliceous pelagic deposits prevail in the northern and southern wing of the SAA, while Calabrian Arc mostly consists of metamorphic exotic terranes (Calabride units, part of the Kabylo-Calabride thrust belt). The Calabrian Arc is a composite terrane of likely Western Alpine origin, accreted on the back of the SAA. Within SAA, tectonic segmentation and variations in structural trend are controlled by thrust partitioning and strike-slip transfer along transverse discontinuities connected with thin-skinned differential rotations. The SAA shows in general much greater amount of shortening in respect of Northern Apennines. Its style is featured by duplexes and relevant out-of-sequence thrusts

Geological surveying in a Metropolitan area: the southern suburbs of Roma

The southern suburbs of Rome were built up for the most part during the second half of the last century. This contribution illustrates the case study of the Ostiense area, located across the Tiber River valley, where the cyty?s expansion has mostly not taken into account the geological and hydrogeological characteristic of the land. For this reason, many buildings and infrastructures of ther area have been damaged by differential dubsidence and flooding. This work proposes a hazard zonation based on the geotechnical, hydrogeological, hydraulic and seismic characteristics of the area, for the purposes of urban development planning and management

The late Messinian Lago-Mare episode in the central Italy: a regional review.

During the Messinian Lago-Mare episode, in the central Mediterranean area, compression- and extension-related basins developed as a consequence of the post-Tortonian evolution of the Tyrrhenian-Apennines system. In particular, in the frontal Apennine zone, which was affected by compressional tectonics, a foreland basin system developed, originating: thrust-top basins (such as Le Vicenne Basin), a foredeep basin (Pescosansonesco-Roccacaramanico) and a foreland basin (Roccamorice-S. Valentino in Abruzzo Citeriore) (fig. 1). Meanwhile, the Tyrrhenian area was affected by a strong subsidence rate with sedimentary basins developed in a syn-rift stage (Tyrrhenian Basin east of the R. Selli lineament, Garigliano plain, Tolfa-Blera Basin and Tuscan late Messinian basins). All these sedimentary basins were characterized by different subsidence rates and sedimentary processes, depending on both the tectonic and the subsiding regime they underwent. We examined foreland, foredeep, thrust-top, extension-related basins, and the results of the Mondragone 1 well in Tyrrhenian Basin.This regional review on the late Messinian Lago-Mare deposits in central Italy shows that the Tyrrhenian rifting process, the accretion of the Apennine thrust belt as well as the increase in subsidence rate in the foreland domain occurred synchronously. The total subsidence rates computed in the area of the Tyrrhenian Basin, which, during the Messinian Lago-Mare episode, was affected by rifting, evidence a different behaviour between the northern and the southern Tyrrhenian (Fig. 2). North of the Tiber delta, the Messinian post-evaporitic sedimentary basins show a mean total subsidence rate of 1 mm/a (Volterra, Val di Fine and Tolfa-Blera basins), whereas in the Garigliano plain the subsidence was at least 4 mm/a. This difference in the syn-rift subsidence could be explained with the segmentation model of the Tyrrhenian –Apennines system along a NNE-SSW lithosphere discontinuity (Cipollari et al., 1999), from Ancona to the Tyrrhenian Basin

Progetto MIUR-SETRIS.Corso di formazione a distanza per insegnanti di Scienze della Scuola media secondaria basato su mezzi multimediali (CD e sito WEB)

Sono state prodotte lezioni pilota di astronomia, chimica,fisica, geologia, matematica, destinate agli studenti della Scuola Media che sono state proposte nella forma di un corso di formazione a distanza agli insegnati di Matematica e Scienze.Oltre ai contenuti scientifici e didattici, sono stati curati anche gli aspetti metodologici e pedagogici

Magnetostratigraphy of the Collepardo Late Pliocene faunal assemblage (Early Villafranchian Triversa Faunal Unit), Ernici Mts., Central Italy

The chronological attribution of the Collepardo mammal faunal site (Ernici Mts., Central Italy) has been disputed for a long time. Recent studies have attributed the faunal site to the Early Villafranchian Triversa Faunal Unit (FU), on the base of the presence of Agriotherium cf. insigne, Sus arvernensis and Pseudodama lyra. In this paper we present magnetostratigraphic results from 27 cores, sampled in a 10 m thick stratigraphic section across the breccia layers and the interspersed red silty clays and travertine layer containing mammal fossils. In all the samples a normal polarity Characteristic Remanent Magnetization (ChRM) component has been isolated. The presence of magnetite as main magnetic carrier and the consistency of ChRM direction throughout different lithologies strongly suggest a primary origin of the isolated component. Taking into consideration the fossil chronological distribution, the normal polarity magnetozone can be correlated with one of the normal magnetic polarity subchrons within the 2An (Gauss) in the GPTS reference scale, corresponding with Early Villafranchian stage in the continental chronology. Our results support the attribution of the Collepardo mammal assemblage to the Triversa FU and, therefore, the "Travertine and Breccias" deposits to the Late Pliocene (Piacenzian)

Structural architecture of the Central Apennine: Interpretation of the Crop 11 seismic profile from the Adriatic coast to the orographic divide

We present an interpretation of the eastern halfportion of the CROP 11 line, a deep reflection seismicprofile 265 km long that cuts across the centralApennines from the Tyrrhenian coast to the Adriaticcoast. In the study area the line cuts across a pile ofthrust sheets that underwent tectonic transport betweenthe Messinian and the Pleistocene. In its easternmostpart, the line runs through the Plio-Pleistocene depositsof the Adriatic foredeep. In the foreland region theCROP 11 line integrates previous information on thecrustal structure derived from petroleum explorationand from deep seismic sounding refraction experiments.In particular, the CROP 11 line confirms the existenceof a very thick sedimentary sequence underlying theMesozoic-Tertiary carbonates of the Apulia Platforminterpreted as the Paleozoic-Triassic sedimentary coverof a pre-Cambrian crystalline basement. In the mountainchain, where the base thrust of the orogenic wedge reachesa depth of about 25 km, this sedimentary sequence appearsto be the deepest geological unit incorporated in the thrustsystem. This interpretation of the CROP 11 profilesuggests an unusual thin-skin tectonic style implyingthe detachment from the original basement and theincorporation in the post-Tortonian tectonic wedge of avery thick Paleozoic-Triassic sedimentary sequencepossibly affected by low-grade metamorphism in thelower part. Other new suggestions from the CROP 11seismic data concern the origin of the Fucino basin, oneof the most remarkable Plio-Pleistocene intramontanebasins. The normal faults bordering this structuraldepression, as other important normal faults present inthe central Apennines (e.g., the Caramanico fault systemin the Majella region), seem to have been controlled bygravitational-collapse processes driven by uplift duringcrustal shortening rather than by a generalized extensionsubsequent to the Apennine compression, as usuallyreported in the geological literature. If this interpretationis correct, the strong seismic activity in correspondenceto the Apennine watershed may be related to the veryrecent increase in the structural relief caused by an outof-sequence propagation of the active thrusts

Regional gravity anomaly map and crustal model of the Central-Southern Apennines,

The deep structures of the Central–Southern Apennines are analysed on the basis of the regional component of gravity anomalies, obtained applying a stripping technique. This procedure allows the accurate removal of the gravimetric effect of the three-dimensional shallow (within the first 10 km) geological bodies from the observed Bouguer anomaly. The resulting anomaly map differs quite significantly from the Bouguer anomaly map, providing new constraints on the nature of the deeper part of the crust and on the upper mantle. The stripping reveals that the regional gravity lows are shifted westward in comparison with Bouguer anomaly lows. Moreover, the gravimetric pattern indicates a lack of cylindrism for the deep structures of the Apennine Chain, which in the study area can be roughly divided into three main segments. The observed differences between the gravity anomalies pattern of the Central Apennines and that of the Southern Apennines are marked.The integration of gravimetric results with other geophysical data suggests that: (i) a ramp-dominated style for the buried Apulia (Adria) units and part of the underlying basement is compatible with gravimetric data and (ii) most of the regional gravity anomalies in the Central Apennines seem to originate within the lower crust