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array:24 [ "pii" => "S2173572723001327" "issn" => "21735727" "doi" => "10.1016/j.medine.2023.07.011" "estado" => "S300" "fechaPublicacion" => "2024-03-01" "aid" => "1912" "copyright" => "Elsevier España, S.L.U. and SEMICYUC" "copyrightAnyo" => "2023" "documento" => "article" "crossmark" => 1 "subdocumento" => "fla" "cita" => "Med Intensiva. 2024;48:133-41" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "Traduccion" => array:1 [ "en" => array:19 [ "pii" => "S0210569123002152" "issn" => "02105691" "doi" => "10.1016/j.medin.2023.07.002" "estado" => "S300" "fechaPublicacion" => "2024-03-01" "aid" => "1912" "copyright" => "Elsevier España, S.L.U. y SEMICYUC" "documento" => "article" "crossmark" => 1 "subdocumento" => "fla" "cita" => "Med Intensiva. 2024;48:133-41" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "en" => array:13 [ "idiomaDefecto" => true "cabecera" => "<span class="elsevierStyleTextfn">Original article</span>" "titulo" => "Characteristics and risk factors associated with mortality during the first cycle of prone secondary to ARDS due to SARS-CoV-2 pneumonia" "tienePdf" => "en" "tieneTextoCompleto" => "en" "tieneResumen" => array:2 [ 0 => "en" 1 => "es" ] "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "133" "paginaFinal" => "141" ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Características y factores de riesgo asociados a mortalidad durante el primer ciclo de prono por SDRA secundario a neumonía por SARS-CoV-2" ] ] "contieneResumen" => array:2 [ "en" => true "es" => true ] "contieneTextoCompleto" => array:1 [ "en" => true ] "contienePdf" => array:1 [ "en" => true ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:8 [ "identificador" => "fig0010" "etiqueta" => "Figure 2" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr2.jpeg" "Alto" => 2890 "Ancho" => 2170 "Tamanyo" => 368930 ] ] "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0290" "detalle" => "Figure " "rol" => "short" ] ] "descripcion" => array:1 [ "en" => "<p id="spar0010" class="elsevierStyleSimplePara elsevierViewall">Panel A. Patient mortality according to the different PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) changes after 24<span class="elsevierStyleHsp" style=""></span>h of prone positioning. Panel B. Patient mortality according to the different PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) change after 24<span class="elsevierStyleHsp" style=""></span>h of prone positioning in patients with baseline<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> 100<span class="elsevierStyleHsp" style=""></span>mmHg.</p>" ] ] ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "Cecilia Gonzalez, Gabriel Musso, Jesica Rodriguez Louzan, Juan Manuel Dominguez, Celeste Gomez, Gabriel Appendino, Analía Abaca, Lucio Clemente, Diana Latasa, Martin Manago, Carlos Lovesio, Elisa Estenssoro" "autores" => array:12 [ 0 => array:2 [ "nombre" => "Cecilia" "apellidos" => "Gonzalez" ] 1 => array:2 [ "nombre" => "Gabriel" "apellidos" => "Musso" ] 2 => array:2 [ "nombre" => "Jesica Rodriguez" "apellidos" => "Louzan" ] 3 => array:2 [ "nombre" => "Juan Manuel" "apellidos" => "Dominguez" ] 4 => array:2 [ "nombre" => "Celeste" 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"paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "142" "paginaFinal" => "154" ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Asociación de la obesidad en la evolución de los pacientes críticos afectados por COVID-19" ] ] "contieneResumen" => array:2 [ "en" => true "es" => true ] "contieneTextoCompleto" => array:1 [ "en" => true ] "contienePdf" => array:1 [ "en" => true ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:8 [ "identificador" => "fig0015" "etiqueta" => "Figure 3" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr3.jpeg" "Alto" => 969 "Ancho" => 1675 "Tamanyo" => 99871 ] ] "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0015" "detalle" => "Figure " "rol" => "short" ] ] "descripcion" => array:1 [ "en" => "<p id="spar0015" class="elsevierStyleSimplePara elsevierViewall">Additive Cox models with penalised smooth splines adjusted by confounding factors.</p>" ] ] ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "Alejandro Rodríguez, Ignacio Martín-Loeches, Gerard Moreno, Emili Díaz, Cristina Ferré, Melina Salgado, Judith Marín-Corral, Angel Estella, Jordi Solé-Violán, Sandra Trefler, Rafael Zaragoza, Lorenzo Socias, Marcio Borges-Sa, Marcos I Restrepo, Juan J Guardiola, Luis F Reyes, Antonio Albaya-Moreno, Alfonso Canabal Berlanga, María del Valle Ortiz, Juan Carlos Ballesteros, Susana Sancho Chinesta, Juan Carlos Pozo Laderas, Josep Gómez, María Bodí" "autores" => array:25 [ 0 => array:2 [ "nombre" => "Alejandro" "apellidos" => "Rodríguez" ] 1 => array:2 [ "nombre" => "Ignacio" "apellidos" => "Martín-Loeches" ] 2 => array:2 [ "nombre" => "Gerard" "apellidos" => "Moreno" ] 3 => array:2 [ "nombre" => "Emili" "apellidos" => "Díaz" ] 4 => array:2 [ "nombre" => "Cristina" "apellidos" => "Ferré" ] 5 => array:2 [ "nombre" => "Melina" "apellidos" => "Salgado" ] 6 => array:2 [ "nombre" => "Judith" "apellidos" => "Marín-Corral" ] 7 => array:2 [ "nombre" => "Angel" "apellidos" => "Estella" ] 8 => array:2 [ "nombre" => "Jordi" "apellidos" => "Solé-Violán" ] 9 => array:2 [ "nombre" => "Sandra" "apellidos" => "Trefler" ] 10 => array:2 [ "nombre" => "Rafael" "apellidos" => "Zaragoza" ] 11 => array:2 [ "nombre" => "Lorenzo" "apellidos" => "Socias" ] 12 => array:2 [ "nombre" => "Marcio" "apellidos" => "Borges-Sa" ] 13 => array:2 [ "nombre" => "Marcos I" "apellidos" => "Restrepo" ] 14 => array:2 [ "nombre" => "Juan J" "apellidos" => "Guardiola" ] 15 => array:2 [ "nombre" => "Luis F" "apellidos" => "Reyes" ] 16 => array:2 [ "nombre" => "Antonio" "apellidos" => "Albaya-Moreno" ] 17 => array:2 [ "nombre" => "Alfonso Canabal" "apellidos" => "Berlanga" ] 18 => array:2 [ "nombre" => "María del Valle" "apellidos" => "Ortiz" ] 19 => array:2 [ "nombre" => "Juan Carlos" "apellidos" => "Ballesteros" ] 20 => array:2 [ "nombre" => "Susana Sancho" "apellidos" => "Chinesta" ] 21 => array:2 [ "nombre" => "Juan Carlos Pozo" "apellidos" => "Laderas" ] 22 => array:2 [ "nombre" => "Josep" "apellidos" => "Gómez" ] 23 => array:2 [ "nombre" => "María" "apellidos" => "Bodí" ] 24 => array:1 [ "colaborador" => "on behalf COVID-19/SEMCYUC Working group" ] ] ] ] ] "idiomaDefecto" => "en" "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S2173572723001522?idApp=WMIE" "url" => "/21735727/0000004800000003/v1_202403010851/S2173572723001522/v1_202403010851/en/main.assets" ] "itemAnterior" => array:18 [ "pii" => "S2173572724000018" "issn" => "21735727" "doi" => "10.1016/j.medine.2024.01.001" "estado" => "S300" "fechaPublicacion" => "2024-03-01" "aid" => "1966" "documento" => "simple-article" "crossmark" => 1 "subdocumento" => "edi" "cita" => "Med Intensiva. 2024;48:131-2" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "en" => array:10 [ "idiomaDefecto" => true "cabecera" => "<span class="elsevierStyleTextfn">Editorial</span>" "titulo" => "Mechanical Power or the not harming power" "tienePdf" => "en" "tieneTextoCompleto" => "en" "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "131" "paginaFinal" => "132" ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Potencia mecánica o el poder de no hacer daño" ] ] "contieneTextoCompleto" => array:1 [ "en" => true ] "contienePdf" => array:1 [ "en" => true ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "Montse Batlle Solà, Rafael Fernández Fernández" "autores" => array:2 [ 0 => array:2 [ "nombre" => "Montse Batlle" "apellidos" => "Solà" ] 1 => array:2 [ "nombre" => "Rafael Fernández" "apellidos" => "Fernández" ] ] ] ] ] "idiomaDefecto" => "en" "Traduccion" => array:1 [ "es" => array:9 [ "pii" => "S0210569124000019" "doi" => "10.1016/j.medin.2023.12.006" "estado" => "S300" "subdocumento" => "" "abierto" => array:3 [ "ES" => true "ES2" => true "LATM" => true ] "gratuito" => true "lecturas" => array:1 [ "total" => 0 ] "idiomaDefecto" => "es" "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S0210569124000019?idApp=WMIE" ] ] "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S2173572724000018?idApp=WMIE" "url" => "/21735727/0000004800000003/v1_202403010851/S2173572724000018/v1_202403010851/en/main.assets" ] "en" => array:19 [ "idiomaDefecto" => true "cabecera" => "<span class="elsevierStyleTextfn">Original article</span>" "titulo" => "Characteristics and risk factors associated with mortality during the first cycle of prone secondary to ARDS due to SARS-CoV-2 pneumonia" "tieneTextoCompleto" => true "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "133" "paginaFinal" => "141" ] ] "autores" => array:1 [ 0 => array:4 [ "autoresLista" => "Cecilia Gonzalez, Gabriel Musso, Jesica Rodriguez Louzan, Juan Manuel Dominguez, Celeste Gomez, Gabriel Appendino, Analía Abaca, Lucio Clemente, Diana Latasa, Martin Manago, Carlos Lovesio, Elisa Estenssoro" "autores" => array:12 [ 0 => array:4 [ "nombre" => "Cecilia" "apellidos" => "Gonzalez" "email" => array:1 [ 0 => "ceciliagonzalez3383@gmail.com" ] "referencia" => array:2 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] 1 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">*</span>" "identificador" => "cor0005" ] ] ] 1 => array:3 [ "nombre" => "Gabriel" "apellidos" => "Musso" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 2 => array:3 [ "nombre" => "Jesica Rodriguez" "apellidos" => "Louzan" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 3 => array:3 [ "nombre" => "Juan Manuel" "apellidos" => "Dominguez" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 4 => array:3 [ "nombre" => "Celeste" "apellidos" => "Gomez" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 5 => array:3 [ "nombre" => "Gabriel" "apellidos" => "Appendino" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 6 => array:3 [ "nombre" => "Analía" "apellidos" => "Abaca" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 7 => array:3 [ "nombre" => "Lucio" "apellidos" => "Clemente" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 8 => array:3 [ "nombre" => "Diana" "apellidos" => "Latasa" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 9 => array:3 [ "nombre" => "Martin" "apellidos" => "Manago" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 10 => array:3 [ "nombre" => "Carlos" "apellidos" => "Lovesio" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 11 => array:3 [ "nombre" => "Elisa" "apellidos" => "Estenssoro" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">b</span>" "identificador" => "aff0010" ] ] ] ] "afiliaciones" => array:2 [ 0 => array:3 [ "entidad" => "Sanatorio Parque, Bv. Oroño 860, Rosario, Santa Fe, Argentina" "etiqueta" => "a" "identificador" => "aff0005" ] 1 => array:3 [ "entidad" => "Hospital Interzonal de Agudos General San Martín de La Plata, Av. 1 1850, La Plata, Argentina" "etiqueta" => "b" "identificador" => "aff0010" ] ] "correspondencia" => array:1 [ 0 => array:3 [ "identificador" => "cor0005" "etiqueta" => "⁎" "correspondencia" => "Corresponding author." ] ] ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Características y factores de riesgo asociados a mortalidad durante el primer ciclo de prono por SDRA secundario a neumonía por SARS-CoV-2" ] ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:8 [ "identificador" => "fig0005" "etiqueta" => "Figure 1" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr1.jpeg" "Alto" => 2255 "Ancho" => 1175 "Tamanyo" => 132591 ] ] "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0285" "detalle" => "Figure " "rol" => "short" ] ] "descripcion" => array:1 [ "en" => "<p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">Flowchart of ARDS patients due to SARS-CoV2 pneumonia in mechanical ventilation who required prone positioning.</p>" ] ] ] "textoCompleto" => "<span class="elsevierStyleSections"><span id="sec0005" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0105">Introduction</span><p id="par0005" class="elsevierStylePara elsevierViewall">The SARS-CoV-2 pandemic has increased the incidence of adult respiratory distress syndrome (ARDS) and has led to an increased need for rescue treatments for refractory hypoxemia, such as prone position. The physiological basis of the prone position lies in a more homogeneous distribution of the ventilation/lung tissue ratio, secondary to the more uniform opening of previously collapsed alveolar units. Prone position thus decreases overdistension and shear injury secondary to cyclic opening and closing in different alveolar populations and might be associated with lower mechanical ventilation induced injury.<a class="elsevierStyleCrossRefs" href="#bib0005"><span class="elsevierStyleSup">1–9</span></a></p><p id="par0010" class="elsevierStylePara elsevierViewall">Prone position improves oxygenation and decreases mortality in patients with ARDS. However, there is no clear definition of failure to this treatment: the number of prone cycles that determine that the treatment is insufficient has not been determined. On the other hand, the early identification of patients who will exhibit a poor response to prone position allows the consideration of other therapeutic alternatives, which could potentially decrease mortality. The use of ECMO (extracorporeal oxygenation membrane) in this population with hypoxemic respiratory failure and severe ARDS could reduce mortality from 80% to 40% in selected candidates who present with severe, potentially reversible hypoxemia which is not associated with multi-organ failure.<a class="elsevierStyleCrossRefs" href="#bib0040"><span class="elsevierStyleSup">8–14</span></a></p><p id="par0015" class="elsevierStylePara elsevierViewall">The need for a higher number of prone positioning cycles could be attributed to a more serious disease. However, it is unclear whether there are differences in mortality in patients requiring more cycles, or whether this is linked to treatment failure.<a class="elsevierStyleCrossRef" href="#bib0075"><span class="elsevierStyleSup">15</span></a></p><p id="par0020" class="elsevierStylePara elsevierViewall">The objective of our study was to analyze the epidemiological characteristics, oxygenation, and pulmonary mechanics, in patients with ARDS due to SARS-CoV-2 on mechanical ventilation who required prone position.</p><p id="par0025" class="elsevierStylePara elsevierViewall">Secondary objectives were to identify independent determinants of mortality; and, particularly, whether the number of prone cycles was associated with a worse prognosis.</p></span><span id="sec0010" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0110">Methods</span><span id="sec0015" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0115">Settings</span><p id="par0030" class="elsevierStylePara elsevierViewall">This cohort study was conducted in a 33-bed medical-surgical Intensive Care Unit (ICU) in Argentina, which only admitted patients with SARS-CoV-2 pneumonia during the pandemic.</p></span><span id="sec0020" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0120">Inclusion and exclusion criteria</span><p id="par0035" class="elsevierStylePara elsevierViewall">All patients with ARDS on mechanical ventilation admitted between April 1 and September 1, 2021 in whom prone position was utilized due to severe hypoxemia were prospectively included.<a class="elsevierStyleCrossRef" href="#bib0050"><span class="elsevierStyleSup">10</span></a></p><p id="par0040" class="elsevierStylePara elsevierViewall">Additionally, patients with SARS-CoV-2 mechanically ventilated who had required prone position from March 1, 2020 to March 1, 2021 were retrospectively included.</p><p id="par0045" class="elsevierStylePara elsevierViewall">The need for prone position was defined by attending physicians. Patients hospitalized outside the data collection period, those who did not have a record of respiratory mechanics values, and those who did not require prone position, were excluded.</p></span><span id="sec0025" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0125">Variables</span><p id="par0050" class="elsevierStylePara elsevierViewall">We recorded age, sex, comorbidities, APACHE II, and SOFA scores. Prior to turning patients into prone positioning, and 24<span class="elsevierStyleHsp" style=""></span>h after the first session, the following variables were recorded: tidal volume (Vt, in mL/kg of predicted body weight [PBW]), respiratory rate (RR), blood gases, PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>, plateau pressure (cmH<span class="elsevierStyleInf">2</span>O), PEEP (cmH<span class="elsevierStyleInf">2</span>O), static compliance of the respiratory system (mL/cmH<span class="elsevierStyleInf">2</span>O) and delta pressure in airway (ΔP) (Defined as End of Inspiration Pressure [Pinsp] – positive end-expiratory pressure [PEEP]) (cmH<span class="elsevierStyleInf">2</span>O). A high ΔP was defined as >15<span class="elsevierStyleHsp" style=""></span>cmH<span class="elsevierStyleInf">2</span>O. Ventilatory ratio (VR), as a surrogate of deadspace, was estimated as Vt<span class="elsevierStyleHsp" style=""></span>×<span class="elsevierStyleHsp" style=""></span>RR<span class="elsevierStyleHsp" style=""></span>×<span class="elsevierStyleHsp" style=""></span>CO<span class="elsevierStyleInf">2</span>/PBW (kg)<span class="elsevierStyleHsp" style=""></span>×<span class="elsevierStyleHsp" style=""></span>100<span class="elsevierStyleHsp" style=""></span>×<span class="elsevierStyleHsp" style=""></span>37.5; a value >1 correlate with increase deadspace.<a class="elsevierStyleCrossRef" href="#bib0080"><span class="elsevierStyleSup">16</span></a></p><p id="par0055" class="elsevierStylePara elsevierViewall">Respiratory variables were collected in a systematized paper instrument that is used for the daily monitoring and follow-up of patients on mechanical ventilation.</p><p id="par0060" class="elsevierStylePara elsevierViewall">Each prone session lasted for 24<span class="elsevierStyleHsp" style=""></span>h. Number of prone position cycles performed were registered.</p><p id="par0065" class="elsevierStylePara elsevierViewall">After 24<span class="elsevierStyleHsp" style=""></span>h in prone position, the percentage of increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ratio related to the initial value was also recorded. PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ratio was obtained while the patient was in prone position. Hospital mortality, rate of tracheostomy, use of corticosteroids, use of neuromuscular blocking agents, length of hospitalization and UCI length of stay was also recorded.</p><p id="par0070" class="elsevierStylePara elsevierViewall">Baseline characteristics, severity scores, respiratory variables before and after the first 24<span class="elsevierStyleHsp" style=""></span>h in prone position, PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ratio changes and ΔP were compared between survivors and non-survivors. Because the subgroup of patients with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> <100<span class="elsevierStyleHsp" style=""></span>mmHg (Severe ARDS) might be potential candidates for ECMO, they were also analyzed as a subgroup to discern if response to prone and outcomes were similar to those of the rest of the patients in the study.</p><p id="par0075" class="elsevierStylePara elsevierViewall">Patients were classified according to the behavior of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after the first session of prone position, according to the increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> in: 1) no increase, 2) increase <25%, 3) increase between 25 and 50%, 4) increase >50%.</p></span><span id="sec0030" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0130">Statistical analysis</span><p id="par0080" class="elsevierStylePara elsevierViewall">Continuous variables are expressed as mean<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>standard deviation or median and percentiles [0.25–0.75], according to the nature of the variables. Categorical variables are expressed as numbers and percentages [n (%)]. Statistical analysis was performed with t test for continuous variables of normal distribution, Mann–Whitney’s U test for continuous variables of non-normal distribution, Chi² for categorical variables and <span class="elsevierStyleItalic">chi<span class="elsevierStyleSup">2</span> trend</span> for evolutionary categorical variables. For the analysis of the effects of prone position on oxygenation and respiratory mechanics at baseline and at 24<span class="elsevierStyleHsp" style=""></span>h, Wilcoxon signed-rank test was used.</p><p id="par0085" class="elsevierStylePara elsevierViewall">A value of p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.05 was defined as statistically significant.</p><p id="par0090" class="elsevierStylePara elsevierViewall">Independent factors associated with in-hospital mortality were identified by means of Cox regression. Variables that presented a p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.10 in univariate analysis or that were physiologically or clinically relevant were chosen for the regression model.</p><p id="par0095" class="elsevierStylePara elsevierViewall">For the analysis of the data, the statistical software SPSS, version <span class="elsevierStyleItalic">Statistics</span> 25, was used.</p></span><span id="sec0035" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0135">Ethical issues</span><p id="par0100" class="elsevierStylePara elsevierViewall">This study was approved by the Institutional Review Board and informed consent was waived, since it was considered as posing minimal risk to the participants due to its retrospective study design.</p></span></span><span id="sec0040" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0140">Results</span><p id="par0105" class="elsevierStylePara elsevierViewall">Over an 18-month period, 412 patients with SARS-CoV-2 requiring invasive mechanical ventilation were admitted to the ICU. In 308 of them prone position was used; however, in 35, clinical data were incomplete, so they were not included for analysis. We included 273 patients; of these, 126 were admitted between January 1, 2020, and March 1, 2021 and 147 between April 1, 2021, and September 1, 2021 (<a class="elsevierStyleCrossRef" href="#fig0005">Fig. 1</a>)</p><elsevierMultimedia ident="fig0005"></elsevierMultimedia><p id="par0110" class="elsevierStylePara elsevierViewall">Of the 273 patients analyzed, 166 had moderate ARDS with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ratio <150<span class="elsevierStyleHsp" style=""></span>mmHg and 107 severe ARDS (PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> <100<span class="elsevierStyleHsp" style=""></span>mmHg). Age was 59 [49−67] years, with differences between survivors and non-survivors; 62 patients (18%) were female. Regarding comorbidities, 113 (32%) had obesity, 112 (32%) arterial hypertension, 52 (15%) diabetes type II, and 43 (12%) chronic obstructive pulmonary disease (COPD). This last comorbidity was the only one that differed between survivors and non-survivors. The scores APACHE II and SOFA were 13 [9–16] and 3 [2–5] respectively (<a class="elsevierStyleCrossRef" href="#tbl0005">Table 1</a>).</p><elsevierMultimedia ident="tbl0005"></elsevierMultimedia><p id="par0115" class="elsevierStylePara elsevierViewall">The PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> immediately prior to the start of the first prone cycle was 116 [97–135]<span class="elsevierStyleHsp" style=""></span>mmHg in the total group without differences between survivors and in non-survivors. After 24<span class="elsevierStyleHsp" style=""></span>h in prone position, PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> was 182 [150–222]<span class="elsevierStyleHsp" style=""></span>mmHg in the total group; with significant differences between survivors vs. non-survivors (207<span class="elsevierStyleHsp" style=""></span>mmHg [174−236] vs.170<span class="elsevierStyleHsp" style=""></span>mmHg [138−210]; p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001) (<a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>). ICU and hospital length of stay for the entire population and for survivors and non-survivors is shown in <a class="elsevierStyleCrossRef" href="#tbl0010">Table 2</a>.</p><elsevierMultimedia ident="tbl0010"></elsevierMultimedia><p id="par0120" class="elsevierStylePara elsevierViewall">There were no differences in baseline ΔP between survivors and non-survivors (13 [11–15] vs. 13 [11–15], respectively, but the response of both subgroups to prone position was different (12 [11–14] vs. 13 [12–15]; p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.00. Fifty-nine (21%) patients presented with values of ΔP >15<span class="elsevierStyleHsp" style=""></span>cmH<span class="elsevierStyleInf">2</span>O and in 37 (13%) patients ΔP was elevated after proning. In the entire group, static compliance of the respiratory system in supine position was 30 [25−38]<span class="elsevierStyleHsp" style=""></span>mL/cmH<span class="elsevierStyleInf">2</span>O, and 32 [26−39]<span class="elsevierStyleHsp" style=""></span>mL/cmH<span class="elsevierStyleInf">2</span>O after prone positioning (p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.01); displaying significant differences between survivors and nonsurvivors. Survivors had 31 [25−38] in supine and 33[28−39]<span class="elsevierStyleHsp" style=""></span>mL/cmH<span class="elsevierStyleInf">2</span>O after prone (p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001). Non survivors had 29 [24–35] in supine and 31[23–35]<span class="elsevierStyleHsp" style=""></span>mL/cmH<span class="elsevierStyleInf">2</span>O after prone position (p<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.36) (<a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>).</p><elsevierMultimedia ident="tbl0015"></elsevierMultimedia><p id="par0125" class="elsevierStylePara elsevierViewall">Regarding the surrogates of dead space, baseline CO<span class="elsevierStyleInf">2</span> was 48 [42−58] and after the first prone cycle it was 47 [41–52] (p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.01). There were differences between survivors and non-survivors but they did not reach statistical significance. We did not find differences in the respiratory ratio before and after prone treatment (<a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a>).</p><p id="par0130" class="elsevierStylePara elsevierViewall">After 24<span class="elsevierStyleHsp" style=""></span>h in prone position, and compared to baseline values, 22 patients (8%) had the same value or experienced a decrease in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2;</span> 46 patients (16%) showed an increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ≤25%; 55 patients (21%) had an increase of 25%–50%; and 150 patients (55%) had an increase >50%. Mortality in each group was, respectively, 86%, 87%, 72%, 50% (p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001) (<a class="elsevierStyleCrossRef" href="#tbl0015">Table 3</a> panel A and <a class="elsevierStyleCrossRef" href="#fig0010">Fig. 2</a>, panel A).</p><elsevierMultimedia ident="fig0010"></elsevierMultimedia><p id="par0135" class="elsevierStylePara elsevierViewall">Of the 107 patients who presented with severe ARDS with baseline PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> values, <100<span class="elsevierStyleHsp" style=""></span>mmHg, 64 (60%) died; however, that initial PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> value was not associated with higher mortality. Patients who managed to raise their oxygenation by more than 50% presented a mortality rate comparable to those with initial PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> >100<span class="elsevierStyleHsp" style=""></span>mmHg and a similar increase in oxygenation. Having debuted with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2,</span> ratio <100<span class="elsevierStyleHsp" style=""></span>mmHg did not imply that the patient was refractory to prone position. The baseline absolute value of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> <100<span class="elsevierStyleHsp" style=""></span>mmHg showed no association with higher mortality in this cohort of patients but the inability to raise PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> more than 50% from baseline after the first prone cycle did (<a class="elsevierStyleCrossRefs" href="#tbl0010">Table 2, Table 3</a> panel B and <a class="elsevierStyleCrossRef" href="#fig0010">Fig. 2</a>, panel B).</p><p id="par0140" class="elsevierStylePara elsevierViewall">Variables that were independently associated with mortality according to Cox regression were age, percentage of increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after 24<span class="elsevierStyleHsp" style=""></span>h in prone position, and number of prone cycles (<a class="elsevierStyleCrossRef" href="#tbl0020">Table 4</a>).</p><elsevierMultimedia ident="tbl0020"></elsevierMultimedia></span><span id="sec0045" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0145">Discussion</span><p id="par0145" class="elsevierStylePara elsevierViewall">Our most important finding was that after the first 24<span class="elsevierStyleHsp" style=""></span>h in the prone position, the percentage of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> increase over baseline was independently associated with higher mortality, beyond the absolute value. That might suggest that patients who raise PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> <50% above baseline could be refractory to, or failed to, prone treatment. In addition, with each consecutive, additional cycle of prone the chances of survival decreased significantly. Older age was also a factor that was associated with lower survival.</p><p id="par0150" class="elsevierStylePara elsevierViewall">A higher mortality in severe ARDS with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> values <100<span class="elsevierStyleHsp" style=""></span>mmHg has been described in the literature.<a class="elsevierStyleCrossRefs" href="#bib0085"><span class="elsevierStyleSup">17–19</span></a> In our cohort, the initial value of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> was not related to prognosis; instead, the determinant was the change in the PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after having been in prone position for 24<span class="elsevierStyleHsp" style=""></span>h. In addition, this was an early determinant, since it evident at 24<span class="elsevierStyleHsp" style=""></span>h of treatment―which could help identifying patients who would most benefit in terms of mortality.</p><p id="par0155" class="elsevierStylePara elsevierViewall">Our study includes a large population of patients undergoing prone position comprehensively analyzed from the physiological point of view; and it presents an exhaustive analysis of oxygenation, number of prone cycles and respiratory mechanics changes. Other authors have described a similar change in mortality associated with the percentage increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ratio in patients with ARDS and prone.<a class="elsevierStyleCrossRefs" href="#bib0100"><span class="elsevierStyleSup">20,21</span></a></p><p id="par0160" class="elsevierStylePara elsevierViewall">Whereas Langer et al. studied 648 patients in prone position, only 78 were extensively analyzed. Additionally, these authors included a small number of patients and a mix of mild, moderate and severe ARDS, therefore the final effect of prone position on oxygenation might have been attenuated.<a class="elsevierStyleCrossRef" href="#bib0110"><span class="elsevierStyleSup">22</span></a> Camporota et al. described a mixed population of patients, with COVID-19 and non-COVID-19 ARDS.<a class="elsevierStyleCrossRef" href="#bib0120"><span class="elsevierStyleSup">24</span></a> Cunha et al. included 412 patients in prone position with COVID-19 ARDS; while the authors describe a positive response on oxygenation, they attribute their high mortality rates to pre-existing health status and comorbidities.<a class="elsevierStyleCrossRef" href="#bib0115"><span class="elsevierStyleSup">23</span></a></p><p id="par0165" class="elsevierStylePara elsevierViewall">Langer et al., in a subgroup of COVID-19 patients who received prone position, considered those who presented a 20<span class="elsevierStyleHsp" style=""></span>mmHg increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> as responders to the treatment. However, this improvement can be considered as having little significance in clinical practice.<a class="elsevierStyleCrossRef" href="#bib0110"><span class="elsevierStyleSup">22</span></a> In our cohort of patients, the group that increased PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> by 20<span class="elsevierStyleHsp" style=""></span>mmHg (which corresponded to a 25% increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> from baseline approximately) had 87% mortality, and a 30% higher risk of dying than those who increased PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> by 50%. Patients who were unable to raise PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> values to more than 50% exhibited a very high mortality rate, between 72 and 87%. That behavior was similar to that described by Park et al. and Lee et al.<a class="elsevierStyleCrossRefs" href="#bib0100"><span class="elsevierStyleSup">20,21</span></a></p><p id="par0170" class="elsevierStylePara elsevierViewall">In the Brazilian multicenter observational study of 574 patients with COVID-19 who received prone positioning, the authors classified the response the same way as Langer et al. While they had a larger number of patients who responded to treatment (72%) mortality was similar in both responders and non-responders.<a class="elsevierStyleCrossRef" href="#bib0115"><span class="elsevierStyleSup">23</span></a></p><p id="par0175" class="elsevierStylePara elsevierViewall">We believe that using an absolute value of increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> to define responders to treatment does not adequately reflect the response of patients with varying degrees of ARDS severity. For example, in a patient starting prone treatment with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> of 50<span class="elsevierStyleHsp" style=""></span>mmHg, a 20<span class="elsevierStyleHsp" style=""></span>mmHg-increase represents a response of almost 50%, while in a patient starting with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> of 140<span class="elsevierStyleHsp" style=""></span>mmHg an increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> of 20<span class="elsevierStyleHsp" style=""></span>mmHg is barely an increase of 15%. In our cohort of patients, the evolution of these cases was very different.</p><p id="par0180" class="elsevierStylePara elsevierViewall">We had classified patients according to the behavior of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after the first session of prone position, the subgroup of patients that increased PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> by 20<span class="elsevierStyleHsp" style=""></span>mmHg (corresponding to a 25% increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> from baseline had approximately 87% mortality, and a 30% higher risk of death than those that increased PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> by 50%. In our population, patients who were unable to raise the values of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> by more than 50%, had a remarkably high mortality, between 72 and 87%.</p><p id="par0185" class="elsevierStylePara elsevierViewall">Our findings regarding the change of oxygenation in response to prone position are consistent with the results of other researchers, both in COVID-19 and non-COVID-19 populations.<a class="elsevierStyleCrossRefs" href="#bib0100"><span class="elsevierStyleSup">20,21</span></a> A recently published observational study comparing both diseases demonstrate, after a sensitivity analysis, that the percentage of change in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after the first prone cycle predicted weaning of mechanical ventilation at 90 days, with an AUROC of 0.87.<a class="elsevierStyleCrossRef" href="#bib0105"><span class="elsevierStyleSup">21</span></a> Similarly, a retrospective study in moderate and severe COVID-19 and non-COVID-19 ARDS patients suggests a similar response to oxygenation after administering the first prone position cycle.<a class="elsevierStyleCrossRef" href="#bib0100"><span class="elsevierStyleSup">20</span></a></p><p id="par0190" class="elsevierStylePara elsevierViewall">The duration of prone position required to improve oxygenation in a sustained manner is unknown. Short cycles have been described as ineffective<a class="elsevierStyleCrossRef" href="#bib0125"><span class="elsevierStyleSup">25</span></a>; but it has not been established how many cycles, and how prolonged they should be, to consistently reverse hypoxemia. For example, Guerin et al. utilized 4.4 cycles per patient of 17<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>3<span class="elsevierStyleHsp" style=""></span>h each in the PROSEVA study.<a class="elsevierStyleCrossRef" href="#bib0045"><span class="elsevierStyleSup">9</span></a></p><p id="par0195" class="elsevierStylePara elsevierViewall">It has been suggested that SARS-CoV-2 as a cause of ARDS behaves more aggressively and might require a higher number of cycles. Langer et al., in the abovementioned study, reported an utilization of 3 [1–4] prone position cycles, although the percentage of patients who received this therapeutic maneuver was strikingly high, and this may have affected the results.<a class="elsevierStyleCrossRef" href="#bib0110"><span class="elsevierStyleSup">22</span></a> Camporota et al. reported a higher number of prone cycles in the COVID-19 population compared to non-COVID-19 ARDS (4 [2–6] vs. 2 [1–3], respectively).<a class="elsevierStyleCrossRef" href="#bib0120"><span class="elsevierStyleSup">24</span></a> Cunha et al. reported 2 [1–3] sessions in COVID-19 patients, and found, as we did, that the number of prone sessions needed was independently associated with higher mortality.<a class="elsevierStyleCrossRef" href="#bib0115"><span class="elsevierStyleSup">23</span></a></p><p id="par0200" class="elsevierStylePara elsevierViewall">On the other hand, the need to extend prone treatment identifies patients with poorer response in terms of oxygenation, or with an initial adequate response that cannot be sustained over time. Patients with a higher need for prone cycles or with a requirement for longer cycles are likely to have more severe lung disease. In addition, the chance of surviving with each subsequent cycle of prone treatment decreases. The delay in early identification of these patients might exclude them from other rescue therapies for severe hypoxemia which might have been applied earlier, such as ECMO.<a class="elsevierStyleCrossRefs" href="#bib0065"><span class="elsevierStyleSup">13,14</span></a> Therefore, patients who fail to increase PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> by more than 50%, or who increase it but subsequently deteriorate oxygenation and require additional prone cycles, should be readily evaluated for other treatments for refractory hypoxemia, since the mortality rate in these group might exceed 80%.<a class="elsevierStyleCrossRef" href="#bib0085"><span class="elsevierStyleSup">17</span></a></p><p id="par0205" class="elsevierStylePara elsevierViewall">Patient age might be another factor contributing to decision-making. In our study, older patients had higher mortality, in agreement with what other researchers found: from the beginning of the pandemic, increasing age was a risk factor for severe illness due to COVID-19.<a class="elsevierStyleCrossRefs" href="#bib0020"><span class="elsevierStyleSup">4,25–27</span></a> Also, in the subgroup of patients requiring critical care, older age was associated with higher mortality. Recently, a study showed that elderly patients with COVID-19 who required life-sustaining treatments in the ICU had higher mortality compared to other elderly patients with similar treatments who were admitted for other diseases than COVID-19.<a class="elsevierStyleCrossRefs" href="#bib0135"><span class="elsevierStyleSup">27,28</span></a></p><p id="par0210" class="elsevierStylePara elsevierViewall">Our study has strengths and weaknesses. Since it is an observational study carried out in a single centre, it is subjected to biases and possible residual confounders. As we did not make a sample size calculation, lack of power for some comparisons might have occurred. A subgroup of data, corresponding to the first wave of COVID-19, was collected retrospectively. Most of the data, however, were recorded prospectively, using the same collection instrument used for routine daily monitoring in the ICU. Finally, our conclusions should only apply to patients with ARDS secondary to COVID-19 since there is no control group composed of patients with ARDS from other causes. Nevertheless, this study has several strengths: we include a large number of patients, and our findings are in line with the results of other researchers’ results. We provide novel information regarding prone treatment in patients with ARDS, which might be useful for early decision-making in severely compromised patients, underscoring the need of escalating therapies in this group.</p></span><span id="sec0050" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0150">Conclusions</span><p id="par0215" class="elsevierStylePara elsevierViewall">The response in prone after the first 24<span class="elsevierStyleHsp" style=""></span>h defined ARDS trajectory, rather than the baseline PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>: an increase of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> >50% after the first cycle of prone position is associated with lower mortality, even if the baseline PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> is low.</p></span><span id="sec0055" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0155">Authors’ contributions</span><p id="par0220" class="elsevierStylePara elsevierViewall">CL is the study lead and guarantor for this paper. CG, GM, JMD, MM, contributed to conception and design of the study. JRL, SC, AL, JR, GS, LF, AR, EB, AA, LC. CG, JMD and EE performed the main statistical analysis, and EE has critically evaluated those results. CG, GM mainly wrote the first draft of this paper, and MM, GM, CL, EE revised it critically for important intellectual content. All authors read and approved the final manuscript.</p></span><span id="sec0060" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0160">Funding</span><p id="par0225" class="elsevierStylePara elsevierViewall">There was no funding for this study.</p></span><span id="sec0065" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0165">Availability of data and materials</span><p id="par0230" class="elsevierStylePara elsevierViewall">The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.</p></span><span id="sec0070" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0170">Ethics approval and consent to participate</span><p id="par0235" class="elsevierStylePara elsevierViewall">This study was approved by the institutional review board and has informed consent. This study was considered as posing minimal risk to the study participants because of its retrospective study design.</p><p id="par0240" class="elsevierStylePara elsevierViewall">All authors consent publication of this paper.</p></span><span id="sec0075" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0175">Conflict of interest</span><p id="par0245" class="elsevierStylePara elsevierViewall">The authors have no conflicts of interest to declare.</p></span></span>" "textoCompletoSecciones" => array:1 [ "secciones" => array:15 [ 0 => array:3 [ "identificador" => "xres2098566" "titulo" => "Abstract" "secciones" => array:8 [ 0 => array:2 [ "identificador" => "abst0005" "titulo" => "Objective" ] 1 => array:2 [ "identificador" => "abst0010" "titulo" => "Design" ] 2 => array:2 [ "identificador" => "abst0015" "titulo" => "Setting" ] 3 => array:2 [ "identificador" => "abst0020" "titulo" => "Patients" ] 4 => array:2 [ "identificador" => "abst0025" "titulo" => "Interventions" ] 5 => array:2 [ "identificador" => "abst0030" "titulo" => "Main variables of interest" ] 6 => array:2 [ "identificador" => "abst0035" "titulo" => "Results" ] 7 => array:2 [ "identificador" => "abst0040" "titulo" => "Conclusions" ] ] ] 1 => array:2 [ "identificador" => "xpalclavsec1788186" "titulo" => "Keywords" ] 2 => array:3 [ "identificador" => "xres2098565" "titulo" => "Resumen" "secciones" => array:8 [ 0 => array:2 [ "identificador" => "abst0045" "titulo" => "Objetivo" ] 1 => array:2 [ "identificador" => "abst0050" "titulo" => "Diseño" ] 2 => array:2 [ "identificador" => "abst0055" "titulo" => "Ambito" ] 3 => array:2 [ "identificador" => "abst0060" "titulo" => "Pacientes" ] 4 => array:2 [ "identificador" => "abst0065" "titulo" => "Intervenciones" ] 5 => array:2 [ "identificador" => "abst0070" "titulo" => "Principales variables de interés" ] 6 => array:2 [ "identificador" => "abst0075" "titulo" => "Resultados" ] 7 => array:2 [ "identificador" => "abst0080" "titulo" => "Conclusiones" ] ] ] 3 => array:2 [ "identificador" => "xpalclavsec1788185" "titulo" => "Palabras clave" ] 4 => array:2 [ "identificador" => "sec0005" "titulo" => "Introduction" ] 5 => array:3 [ "identificador" => "sec0010" "titulo" => "Methods" "secciones" => array:5 [ 0 => array:2 [ "identificador" => "sec0015" "titulo" => "Settings" ] 1 => array:2 [ "identificador" => "sec0020" "titulo" => "Inclusion and exclusion criteria" ] 2 => array:2 [ "identificador" => "sec0025" "titulo" => "Variables" ] 3 => array:2 [ "identificador" => "sec0030" "titulo" => "Statistical analysis" ] 4 => array:2 [ "identificador" => "sec0035" "titulo" => "Ethical issues" ] ] ] 6 => array:2 [ "identificador" => "sec0040" "titulo" => "Results" ] 7 => array:2 [ "identificador" => "sec0045" "titulo" => "Discussion" ] 8 => array:2 [ "identificador" => "sec0050" "titulo" => "Conclusions" ] 9 => array:2 [ "identificador" => "sec0055" "titulo" => "Authors’ contributions" ] 10 => array:2 [ "identificador" => "sec0060" "titulo" => "Funding" ] 11 => array:2 [ "identificador" => "sec0065" "titulo" => "Availability of data and materials" ] 12 => array:2 [ "identificador" => "sec0070" "titulo" => "Ethics approval and consent to participate" ] 13 => array:2 [ "identificador" => "sec0075" "titulo" => "Conflict of interest" ] 14 => array:1 [ "titulo" => "References" ] ] ] "pdfFichero" => "main.pdf" "tienePdf" => true "fechaRecibido" => "2023-03-31" "fechaAceptado" => "2023-07-07" "PalabrasClave" => array:2 [ "en" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Keywords" "identificador" => "xpalclavsec1788186" "palabras" => array:8 [ 0 => "ARDS" 1 => "Decubitus prone" 2 => "Prone position" 3 => "COVID" 4 => "SARS-CoV2" 5 => "Prone failure" 6 => "Refractory hypoxemia" 7 => "ECMO" ] ] ] "es" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Palabras clave" "identificador" => "xpalclavsec1788185" "palabras" => array:8 [ 0 => "SDRA" 1 => "Prono al decúbito" 2 => "Posición prona" 3 => "COVID" 4 => "SARS-CoV2" 5 => "Fallo prono" 6 => "Hipoxemia refractaria" 7 => "ECMO" ] ] ] ] "tieneResumen" => true "resumen" => array:2 [ "en" => array:3 [ "titulo" => "Abstract" "resumen" => "<span id="abst0005" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0010">Objective</span><p id="spar0050" class="elsevierStyleSimplePara elsevierViewall">To analyze characteristics, changes in oxygenation, and pulmonary mechanics, in mechanically ventilated patients with ARDS due to SARS-CoV-2 treated with prone position and evaluate the response to this maneuver.</p></span> <span id="abst0010" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0015">Design</span><p id="spar0055" class="elsevierStyleSimplePara elsevierViewall">Cohort study including patients with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> <150<span class="elsevierStyleHsp" style=""></span>mmHg requiring prone position over 18 months. We classified patients according to PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> changes from basal to 24<span class="elsevierStyleHsp" style=""></span>h after the first prone cycle as: 1) no increase 2) increase <25%, 3) 25%–50% increase 4) increase >50%.</p></span> <span id="abst0015" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0020">Setting</span><p id="spar0060" class="elsevierStyleSimplePara elsevierViewall">33-bed medical-surgical Intensive Care Unit (ICU) in Argentina.</p></span> <span id="abst0020" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0025">Patients</span><p id="spar0065" class="elsevierStyleSimplePara elsevierViewall">273 patients.</p></span> <span id="abst0025" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0030">Interventions</span><p id="spar0070" class="elsevierStyleSimplePara elsevierViewall">None.</p></span> <span id="abst0030" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0035">Main variables of interest</span><p id="spar0075" class="elsevierStyleSimplePara elsevierViewall">Epidemiological characteristics, respiratory mechanics and oxygenation were compared between survivors and non-survivors. Independent factors associated with in-hospital mortality were identified.</p></span> <span id="abst0035" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0040">Results</span><p id="spar0080" class="elsevierStyleSimplePara elsevierViewall">Baseline PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> was 116 [97–135]<span class="elsevierStyleHsp" style=""></span>mmHg (115 [94–136] in survivors vs. 117 [98–134] in non-survivors; p<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.50). After prone positioning, 22 patients (8%) had similar PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> values; 46(16%) increased PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ≤25%; 55 (21%) increased it 25%–50%; and 150 (55%), >50%. Mortality was 86%, 87%, 72% and 50% respectively (p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001). Baseline PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2,</span> <100<span class="elsevierStyleHsp" style=""></span>mmHg did not imply that patients were refractory to prone position. Factors independently associated with mortality were age, percentage increase in PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after 24<span class="elsevierStyleHsp" style=""></span>h being in prone, and number of prone cycles.</p></span> <span id="abst0040" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0045">Conclusions</span><p id="spar0085" class="elsevierStyleSimplePara elsevierViewall">Older patients unable to improve PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> after 24<span class="elsevierStyleHsp" style=""></span>h in prone position and who require >1 cycle might early receive additional treatments for refractory hypoxemia. After the first 24<span class="elsevierStyleHsp" style=""></span>h in the prone position, a low percentage of PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> increase over baseline, beyond the initial value, was independently associated with higher mortality.</p></span>" "secciones" => array:8 [ 0 => array:2 [ "identificador" => "abst0005" "titulo" => "Objective" ] 1 => array:2 [ "identificador" => "abst0010" "titulo" => "Design" ] 2 => array:2 [ "identificador" => "abst0015" "titulo" => "Setting" ] 3 => array:2 [ "identificador" => "abst0020" "titulo" => "Patients" ] 4 => array:2 [ "identificador" => "abst0025" "titulo" => "Interventions" ] 5 => array:2 [ "identificador" => "abst0030" "titulo" => "Main variables of interest" ] 6 => array:2 [ "identificador" => "abst0035" "titulo" => "Results" ] 7 => array:2 [ "identificador" => "abst0040" "titulo" => "Conclusions" ] ] ] "es" => array:3 [ "titulo" => "Resumen" "resumen" => "<span id="abst0045" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0055">Objetivo</span><p id="spar0090" class="elsevierStyleSimplePara elsevierViewall">Analizar las características, cambios en la oxigenación y mecánica pulmonar, en pacientes ventilados mecánicamente con SDRA por SARS-CoV-2 tratados con posición prona, y evaluar la respuesta a esta maniobra.</p></span> <span id="abst0050" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0060">Diseño</span><p id="spar0095" class="elsevierStyleSimplePara elsevierViewall">Estudio de cohorte que incluyó pacientes con PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> <150<span class="elsevierStyleHsp" style=""></span>mmHg que requirieron posición prona durante 18 meses. Se clasificaron los pacientes según los cambios de PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> desde el basal y 24<span class="elsevierStyleHsp" style=""></span>horas después del primer ciclo prono como: 1) Sin aumento 2) Aumento <25%, 3) 25–50% de aumento 4) Aumento >50%.</p></span> <span id="abst0055" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0065">Ambito</span><p id="spar0100" class="elsevierStyleSimplePara elsevierViewall">Unidad de Cuidados Intensivos (UCI) médico-quirúrgica de 33 camas en Argentina.</p></span> <span id="abst0060" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0070">Pacientes</span><p id="spar0105" class="elsevierStyleSimplePara elsevierViewall">273 pacientes.</p></span> <span id="abst0065" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0075">Intervenciones</span><p id="spar0110" class="elsevierStyleSimplePara elsevierViewall">Ninguna.</p></span> <span id="abst0070" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0080">Principales variables de interés</span><p id="spar0115" class="elsevierStyleSimplePara elsevierViewall">Se compararon características epidemiológicas, mecánica respiratoria y oxigenación entre sobrevivientes y no sobrevivientes. Se identificaron factores independientes asociados a la mortalidad hospitalaria.</p></span> <span id="abst0075" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0085">Resultados</span><p id="spar0120" class="elsevierStyleSimplePara elsevierViewall">La PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> basal fue de 116 [97–135]<span class="elsevierStyleHsp" style=""></span>mmHg (115 [94–136] en sobrevivientes vs. 117 [98–134] en no sobrevivientes; p<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0,50). Después de la posición prona, 22 pacientes (8%) tenían valores similares de PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>; 46 (16%) aumentaron PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ≤25%; 55 (21%) lo aumentaron 25%–50%; y 150 (55%), >50%. La mortalidad fue de 86%, 87%, 72% y 50% respectivamente (p<span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0,001). La PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> basal, <100<span class="elsevierStyleHsp" style=""></span>mmHg no implicó que los pacientes fueran refractarios a la posición prona. Los factores asociados independientemente con la mortalidad fueron la edad, el aumento porcentual de PaO<span class="elsevierStyleInf">2/</span>FiO<span class="elsevierStyleInf">2</span> después de 24<span class="elsevierStyleHsp" style=""></span>horas en prona, y el número de ciclos prono.</p></span> <span id="abst0080" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0090">Conclusiones</span><p id="spar0125" class="elsevierStyleSimplePara elsevierViewall">Los pacientes mayores que no pueden mejorar PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> después de 24 horas en posición prona y que requieren más de 1 ciclo podrían recibir tratamientos adicionales para la hipoxemia refractaria. Después de las primeras 24<span class="elsevierStyleHsp" style=""></span>horas en decúbito prono, un bajo porcentaje de aumento de PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> sobre el valor basal, más allá del valor inicial, se asoció de forma independiente con una mayor mortalidad.</p></span>" "secciones" => array:8 [ 0 => array:2 [ "identificador" => "abst0045" "titulo" => "Objetivo" ] 1 => array:2 [ "identificador" => "abst0050" "titulo" => "Diseño" ] 2 => array:2 [ "identificador" => "abst0055" "titulo" => "Ambito" ] 3 => array:2 [ "identificador" => "abst0060" "titulo" => "Pacientes" ] 4 => array:2 [ "identificador" => "abst0065" "titulo" => "Intervenciones" ] 5 => array:2 [ "identificador" => "abst0070" "titulo" => "Principales variables de interés" ] 6 => array:2 [ "identificador" => "abst0075" "titulo" => "Resultados" ] 7 => array:2 [ "identificador" => "abst0080" "titulo" => "Conclusiones" ] ] ] ] "multimedia" => array:6 [ 0 => array:8 [ "identificador" => "fig0005" "etiqueta" => "Figure 1" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr1.jpeg" "Alto" => 2255 "Ancho" => 1175 "Tamanyo" => 132591 ] ] "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0285" "detalle" => "Figure " "rol" => "short" ] ] "descripcion" => array:1 [ "en" => "<p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">Flowchart of ARDS patients due to SARS-CoV2 pneumonia in mechanical ventilation who required prone positioning.</p>" ] ] 1 => array:8 [ "identificador" => "fig0010" "etiqueta" => "Figure 2" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr2.jpeg" "Alto" => 2890 "Ancho" => 2170 "Tamanyo" => 368930 ] ] "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0290" "detalle" => "Figure " "rol" => "short" ] ] "descripcion" => array:1 [ "en" => "<p id="spar0010" class="elsevierStyleSimplePara elsevierViewall">Panel A. Patient mortality according to the different PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) changes after 24<span class="elsevierStyleHsp" style=""></span>h of prone positioning. Panel B. Patient mortality according to the different PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) change after 24<span class="elsevierStyleHsp" style=""></span>h of prone positioning in patients with baseline<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> 100<span class="elsevierStyleHsp" style=""></span>mmHg.</p>" ] ] 2 => array:8 [ "identificador" => "tbl0005" "etiqueta" => "Table 1" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0295" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:2 [ "leyenda" => "<p id="spar0020" class="elsevierStyleSimplePara elsevierViewall">Data are expressed as mean (standard deviation) median [percentiles 0.25–0.75], or n (%).</p>" "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black"> \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">All (n<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>273) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Survivors (n<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>100) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Non-survivors (n<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>173) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">p \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Age (years) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">59[49−67] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">52 [42−62] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">62 [55−69] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Female sex \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">62 (18) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">24 (38) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">38 (62) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.85 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">APACHE II score \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">13 [9–16] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">12 [8–16] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">14 [10–18] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.55 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">SOFA score \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">3 [2–5] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">3 [2–4] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">3 [3–5] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.11 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Arterial hypertension \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">112 (32) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">39 (39) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">73 (42) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.55 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Obesity \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">113 (32) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">42 (42) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">71 (41) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.93 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Diabetes \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">52 (15) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">16 (16) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">36 (20) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.30 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Chronic obstructive pulmonary disease \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">43 (12) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">11 (11) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">33 (19) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.04 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Utilization of corticosteroids \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">272 (99) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">100 (100) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">172 (100) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.52 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Utilization of neuromuscular blockers \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">273 (100) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">100 (100) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">173 (100) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.52 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Duration of mechanical ventilation before prone (hours) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">36 [6−66] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">24 [12−48] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">24 [6−48] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.27 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">pH \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">7.31 [7.30–7.33] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">7.40 [7.32–7.44] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">7.39 [7.30–7.43] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.10 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">CO<span class="elsevierStyleInf">2</span> (mmHg) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">43 [40–48] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">40 [33–50] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">39 [33–49] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.76 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">PaO<span class="elsevierStyleInf">2</span> (mmHg) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">70 [56–85] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">73 [52–87] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">73 [62–87] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.71 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Plasma bicarbonate (meq/L) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">22 [20–23] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">23 [21–26] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">22 [21–25] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.53 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Base excess (meq/L) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">−3 [−6 to 0.5] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">−1.6 [−3 to 2.5] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">−1.8 [−4 to 1] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.24 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">SaO<span class="elsevierStyleInf">2</span> (%) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">92 [87–95] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">94 [92–96] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">94 [91–96] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.34 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Initial PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">116 [97–135] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">115 [94–136] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">117 [98–134] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.53 \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab3472632.png" ] ] ] ] "descripcion" => array:1 [ "en" => "<p id="spar0015" class="elsevierStyleSimplePara elsevierViewall">Baseline characteristics of patients receiving prone position for ARDS due to SARS-CoV-2.</p>" ] ] 3 => array:8 [ "identificador" => "tbl0010" "etiqueta" => "Table 2" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0300" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:2 [ "leyenda" => "<p id="spar0030" class="elsevierStyleSimplePara elsevierViewall">Data are expressed as median [percentiles 0.25–0.75], or n (%).</p>" "tablatextoimagen" => array:1 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black"> \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">All (n<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>273) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Survivors (n<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>100) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Non-survivors (n<span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>173) \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">p \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Initial PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">116 [97–135] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">115 [94–136] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">117 [98–134] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.53 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Post-prone PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (mmHg) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">182 [150–222] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">207 [174–236] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">170 [138–210] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> increase after prone (%) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">55 [26–102] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">74 [49–124] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">42 [17–77] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Baseline PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> ≤100<span class="elsevierStyleHsp" style=""></span>mmHg (n, %) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">107 [39] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">43 [40] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">64 [60] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.38 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Inability to raise PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> >50% in first prone cycle (n, %) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">42 [15] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">9 [21] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">33 [78] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Noradrenaline in first prone cycle (n, %) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">127 (46) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">39 (14) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">88 (32) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.05 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Tracheostomy (n, %) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">241 (88) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">99 (36) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">142 (52) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.79 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Number of prone cycles (n) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1 [1–3] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">1 [1–3] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">2 [1–3] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">ICU length of stay (days) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">12 [8–19] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">13 [10–25] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">12 [7–17] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Hospital length of stay (days) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">18 [12–26] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">21 [15−29] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">17 [10–23] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t"><0.001 \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] "imagenFichero" => array:1 [ 0 => "xTab3472627.png" ] ] ] ] "descripcion" => array:1 [ "en" => "<p id="spar0025" class="elsevierStyleSimplePara elsevierViewall">Oxygenation before and after the first prone position cycle. Comparison between survivors and non-survivors.</p>" ] ] 4 => array:8 [ "identificador" => "tbl0015" "etiqueta" => "Table 3" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at0305" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:2 [ "leyenda" => "<p id="spar0040" class="elsevierStyleSimplePara elsevierViewall">Data are expressed as median [percentiles 0.25−0.75], or n (%).</p>" "tablatextoimagen" => array:3 [ 0 => array:2 [ "tabla" => array:1 [ 0 => """ <table border="0" frame="\n \t\t\t\t\tvoid\n \t\t\t\t" class=""><thead title="thead"><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col"> \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td-with-role" title="\n \t\t\t\t\ttable-head\n \t\t\t\t ; entry_with_role_colgroup " colspan="3" align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">All</th><th class="td-with-role" title="\n \t\t\t\t\ttable-head\n \t\t\t\t ; entry_with_role_colgroup " colspan="3" align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Survivors</th><th class="td-with-role" title="\n \t\t\t\t\ttable-head\n \t\t\t\t ; entry_with_role_colgroup " colspan="3" align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Non-survivors</th></tr><tr title="table-row"><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black"> \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Baseline \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">After 24<span class="elsevierStyleHsp" style=""></span>h in prone \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">p \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Baseline \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">After 24<span class="elsevierStyleHsp" style=""></span>h in prone \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">p \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">Baseline \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">After 24<span class="elsevierStyleHsp" style=""></span>h in prone \t\t\t\t\t\t\n \t\t\t\t\t\t</th><th class="td" title="\n \t\t\t\t\ttable-head\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t" scope="col" style="border-bottom: 2px solid black">p \t\t\t\t\t\t\n \t\t\t\t\t\t</th></tr></thead><tbody title="tbody"><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Plateau pressure (cmH₂O) \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">25 [23–27] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">25 [23–27] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.47 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">25 [23–27] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">25 [23–27] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.66 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.66 \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">25 [23–27] \t\t\t\t\t\t\n \t\t\t\t</td><td class="td" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.93 \t\t\t\t\t\t\n \t\t\t\t</td></tr><tr title="table-row"><td class="td-with-role" title="\n \t\t\t\t\ttable-entry\n \t\t\t\t ; entry_with_role_rowhead " align="left" valign="\n \t\t\t\t\ttop\n \t\t\t\t">Compliance &