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Correlation of the SpO2/FiO2 (S/F) ratio and the PaO2/FiO2 (P/F) ratio in patients with COVID-19 pneumonia
Correlación de la relación SpO2/FiO2 (S/F) y la relación PaO2/FiO2 (P/F) en pacientes con neumonía COVID-19
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SpO<span class="elsevierStyleInf">2</span>: oxygen saturation with pulse oximeter; PaO<span class="elsevierStyleInf">2</span>: oxygen pressure in arterial blood; SatO<span class="elsevierStyleInf">2</span>: oxygen saturation in arterial blood; FiO<span class="elsevierStyleInf">2</span>: fraction of inspired oxygen.</p>" ] ] ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "I. Núñez, A. Soto-Mota" "autores" => array:2 [ 0 => array:2 [ "nombre" => "I." "apellidos" => "Núñez" ] 1 => array:2 [ "nombre" => "A." 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(A) Time scale showing the number of patients admitted to hospital due to COVID-19 (blue area) and the number of patients admitted to the COVID-19 ICU (orange area); the red dotted line shows the percentage of patients admitted to the COVID-19 ICU with respect to the number of hospitalized patients. The transparent red area reflects the home lockdown time. (B) Time scale with overlapping bars representing the percentage of patients over 60 years of age admitted to the ICU in each analyzed week, while the solid orange line reflects the percentage of immunized patients in the population. The red arrow marks the week of start of the vaccination period.</p>" ] ] ] "autores" => array:1 [ 0 => array:2 [ "autoresLista" => "A. González-Castro, E. Cuenca Fito, A. Fernandez, R. Ferrero Franco, J.C. Rodríguez Borregán, C. Gonzalez" "autores" => array:6 [ 0 => array:2 [ "nombre" => "A." "apellidos" => "González-Castro" ] 1 => array:2 [ "nombre" => "E." 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"apellidos" => "Gonzalez" ] ] ] ] ] "idiomaDefecto" => "en" "Traduccion" => array:1 [ "es" => array:9 [ "pii" => "S0210569121001819" "doi" => "10.1016/j.medin.2021.08.002" "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/S0210569121001819?idApp=WMIE" ] ] "EPUB" => "https://multimedia.elsevier.es/PublicationsMultimediaV1/item/epub/S217357272200090X?idApp=WMIE" "url" => "/21735727/0000004600000007/v1_202206240715/S217357272200090X/v1_202206240715/en/main.assets" ] "en" => array:16 [ "idiomaDefecto" => true "cabecera" => "<span class="elsevierStyleTextfn">Scientific letter</span>" "titulo" => "Correlation of the SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (S/F) ratio and the PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (P/F) ratio in patients with COVID-19 pneumonia" "tieneTextoCompleto" => true "saludo" => "Dear Editor," "paginas" => array:1 [ 0 => array:2 [ "paginaInicial" => "408" "paginaFinal" => "410" ] ] "autores" => array:1 [ 0 => array:4 [ "autoresLista" => "A. Kumar, R. Aggarwal, P. Khanna, R. Kumar, A.K. Singh, K.D. Soni, A. Trikha" "autores" => array:7 [ 0 => array:3 [ "nombre" => "A." "apellidos" => "Kumar" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 1 => array:4 [ "nombre" => "R." "apellidos" => "Aggarwal" "email" => array:1 [ 0 => "pathakricha@yahoo.co.in" ] "referencia" => array:2 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">b</span>" "identificador" => "aff0010" ] 1 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">*</span>" "identificador" => "cor0005" ] ] ] 2 => array:3 [ "nombre" => "P." "apellidos" => "Khanna" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 3 => array:3 [ "nombre" => "R." "apellidos" => "Kumar" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 4 => array:3 [ "nombre" => "A.K." "apellidos" => "Singh" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 5 => array:3 [ "nombre" => "K.D." "apellidos" => "Soni" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">b</span>" "identificador" => "aff0010" ] ] ] 6 => array:3 [ "nombre" => "A." "apellidos" => "Trikha" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] ] "afiliaciones" => array:2 [ 0 => array:3 [ "entidad" => "Department of Anaesthesiology, Critical Care and Pain Medicine, AIIMS, New Delhi, India" "etiqueta" => "a" "identificador" => "aff0005" ] 1 => array:3 [ "entidad" => "Critical and Intensive Care, JPNATC, AIIMS, India" "etiqueta" => "b" "identificador" => "aff0010" ] ] "correspondencia" => array:1 [ 0 => array:3 [ "identificador" => "cor0005" "etiqueta" => "⁎" "correspondencia" => "Corresponding author." ] ] ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Correlación de la relación SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (S/F) y la relación PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (P/F) en pacientes con neumonía COVID-19" ] ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:7 [ "identificador" => "fig0005" "etiqueta" => "Figure 1" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr1.jpeg" "Alto" => 1224 "Ancho" => 2091 "Tamanyo" => 264007 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">S/F ratio vs P/F ratio scatter plot. S/F ratio – SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>; P/F ratio – PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>. The line represents the best fit linear relationship SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.80(PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>)<span class="elsevierStyleHsp" style=""></span>+<span class="elsevierStyleHsp" style=""></span>59.8 (<span class="elsevierStyleItalic">p</span><span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001).</p>" ] ] ] "textoCompleto" => "<span class="elsevierStyleSections"><p id="par0005" class="elsevierStylePara elsevierViewall">The clinical spectrum of SARS-CoV-2 infection varies widely ranging from asymptomatic infection to severe viral pneumonia with respiratory failure.<a class="elsevierStyleCrossRef" href="#bib0050"><span class="elsevierStyleSup">1</span></a> Some patients of COVID, who develop respiratory failure have hypoxemia but without signs of respiratory distress also termed as “silent hypoxemia”. This silent hypoxemia may be responsible for the quick deterioration because it gives a false sense of well-being even when the oxygen debt is actually increasing.<a class="elsevierStyleCrossRefs" href="#bib0055"><span class="elsevierStyleSup">2,3</span></a> This mandates regular monitoring of oxygen levels in these patients. SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (S/F) ratio has been found to have good correlation with PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span> (P/F) ratio in adult and pediatric patients with pneumonia, acute respiratory distress syndrome (ARDS) and acute lung injury in various studies.<a class="elsevierStyleCrossRefs" href="#bib0065"><span class="elsevierStyleSup">4–6</span></a> However, in COVID patients, there can be discordance between S/F ratio and P/F ratio due to multiple reasons like shift of oxyhemoglobin dissociation curve to left or right, inaccuracy of SpO<span class="elsevierStyleInf">2</span> at lower levels of saturation and during critical illness.<a class="elsevierStyleCrossRef" href="#bib0080"><span class="elsevierStyleSup">7</span></a> Moreover, the linear correlation between SpO<span class="elsevierStyleInf">2</span> and FiO<span class="elsevierStyleInf">2</span> is lost when SpO<span class="elsevierStyleInf">2</span> is 100% and even the PaO<span class="elsevierStyleInf">2</span> cannot be estimated when SpO<span class="elsevierStyleInf">2</span> is 100%.</p><p id="par0010" class="elsevierStylePara elsevierViewall">The aim of this study was to assess the correlation between S/F and the P/F ratios in patients with COVID pneumonia requiring oxygen therapy and to find whether initial S/F ratio on admission can indicate the requirement of invasive mechanical ventilation (IMV) later in the course of the disease.</p><p id="par0015" class="elsevierStylePara elsevierViewall">This was a prospective observational study conducted in tertiary care COVID center, AIIMS, India after ethical committee approval (IEC-856,4.9.20 dated 14.10.20). Adult patients of ≥18 years of age suffering from moderate to severe COVID (RT-PCR positive) requiring oxygen support or IMV admitted in the intensive care unit (ICU) were included after consent. The patients were administered oxygen with different interfaces as per their baseline SpO<span class="elsevierStyleInf">2</span> and clinical condition to target SpO<span class="elsevierStyleInf">2</span> 92–94% (88–92% in patients with COPD) (life scope bedside monitor from nihonkohden BSM-37630 series). The first arterial blood gas (ABG) analysis (werfen diagnostic corporation, Gem premiere-3000) was done at the time of admission to ICU, and subsequent analysis were done according to clinical condition of patients at the physicians discretion. No specific time points was selected, however, ABG s were done at different FiO<span class="elsevierStyleInf">2</span> in the same patient were recorded. The FiO<span class="elsevierStyleInf">2</span> and SpO<span class="elsevierStyleInf">2</span> were noted at the time of ABG analysis. The FiO<span class="elsevierStyleInf">2</span> delivered with standard facemask was calculated as 0.4 with 5–6 l of oxygen, 0.5 with 6–7 l and 0.6 with >7<span class="elsevierStyleHsp" style=""></span>l of oxygen flow and with non rebreathing mask (NRBM) as 0.9 with 12–15<span class="elsevierStyleHsp" style=""></span>l of flow. The exact FiO<span class="elsevierStyleInf">2</span> was set on the high flow nasal cannula (HFNC) machine and non invasive ventilation (NIV) machine according to the patient requirements. The demographic data, vitals, FiO<span class="elsevierStyleInf">2</span>, S/F ratio and P/F ratio and outcomes were noted.</p><p id="par0020" class="elsevierStylePara elsevierViewall">Assuming significant correlation with <span class="elsevierStyleItalic">r</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.65, the calculated sample size was 80 for 80% power with 5% level of significance at two sided test. A total of 80 patients were enrolled in this study and 249 observations were noted. Data was analyzed using Statistical software packages IBM SPSS, version 21.0. The correlation between S/F ratio and P/F ratio was established using spearmann correlation coefficient and linear regression test was used to develop the equation for S/F and 95% confidence interval were reported.</p><p id="par0025" class="elsevierStylePara elsevierViewall">The mean age of study population was 52<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>13 years and 65% were males. Out of 80 patients, 60 had comorbidities, diabetes mellitus being the most common. The initial respiratory support varied with 37.5% on facemask, 28.7% on NRBM, 8.7% on HFNC/NIV and 25% on IMV (<a class="elsevierStyleCrossRef" href="#sec0025">Supplementary file 1</a>). The mean initial S/F ratio of the patients was 159.77<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>72.14 and mean P/F ratio was 147.86<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>103.26. A scatter plot of S/F and P/F ratios [249 observations] demonstrated a linear correlation (<a class="elsevierStyleCrossRef" href="#fig0005">Fig. 1</a>). The value of r was 0.86, almost similar as in study by Rice et al.<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">9</span></a> (<span class="elsevierStyleItalic">r</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.89) indicating a positive correlation.</p><elsevierMultimedia ident="fig0005"></elsevierMultimedia><p id="par0030" class="elsevierStylePara elsevierViewall">The SF ratio could be predicted well from PF ratio, described by the linear regression equation SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.80 (PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>)<span class="elsevierStyleHsp" style=""></span>+<span class="elsevierStyleHsp" style=""></span>59.8 [95% CI for regression coefficient 0.71–0.89]. Based on this equation, SF ratio of 219 and 299 corresponds to PF ratio of 200 and 300 [<span class="elsevierStyleItalic">p</span><span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001] which is similar to results by Rice et al.<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">9</span></a> (S/F ratio of 235 and 315 surrogates for P/F ratio of 200 and 300). Rice et al.<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">9</span></a> had included patients with ALI/ARDS due to various causes like sepsis, trauma, pneumonia and aspiration and those who were on IMV as per ARDS net trial protocol, whereas we included patients on oxygen as well as patients on IMV.</p><p id="par0035" class="elsevierStylePara elsevierViewall">Recently, Fukuda et al.<a class="elsevierStyleCrossRef" href="#bib0085"><span class="elsevierStyleSup">8</span></a> reported that S/F was useful for predicting the clinical outcomes in mechanically ventilated patients with acute hypoxemic respiratory failure with bilateral opacities. Similarly, Choi et al.<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">9</span></a> reported S/F ratio on admission as a strong predictor of occurrence of ARDS in COVID patients requiring oxygen therapy.</p><p id="par0040" class="elsevierStylePara elsevierViewall">We examined whether initial S/F ratio can indicate the requirement of IMV. In our study, 19 out of 60 patients required IMV later in the course of the disease (ventilated group) and 41 did not (non ventilated). We compared these two groups (<a class="elsevierStyleCrossRef" href="#tbl0005">Table 1</a>). There were no differences in the demographic characteristics, initial S/F ratio and P/F ratio, in the two groups, however, the ventilated group patients were significantly more tachycardiac and tachypneic on admission pointing to the fact that patients were able to maintain oxygenation in the initial phase of the disease at the expense of tachypnea and use of accessory muscles.</p><elsevierMultimedia ident="tbl0005"></elsevierMultimedia><p id="par0045" class="elsevierStylePara elsevierViewall">The median initial S/F ratio [147.5 (71–333)] in our cohort was much lower than in the study by Choi et al.,<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">9</span></a> (287.5 and 452.4) indicating patients were more hypoxemic and in advanced disease in our study probably owing to the delayed presentation to hospital in our cohort. Moreover, factors other than oxygenation e.g. secondary infections, altered sensorium could be reasons for deterioration and mechanical ventilation.</p><p id="par0050" class="elsevierStylePara elsevierViewall">Furthermore, it is imperative to note that some patients with COVID may not have dyspnea despite being hypoxemic, and therefore clinical monitoring of vitals gains paramount importance in these patients. They require aggressive management in order to halt further deterioration.</p><p id="par0055" class="elsevierStylePara elsevierViewall">In conclusion, S/F ratio can be used as surrogate of P/F ratio in patients with COVID pneumonia and can be highly useful in resource limited settings during this pandemic. However, initial S/F ratio on admission cannot indicate the need of invasive ventilation later in the course of the disease.</p><span id="sec0005" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0005">Authors’ contribution</span><p id="par0060" class="elsevierStylePara elsevierViewall">Ashutosh Kumar – acquisition of data, or analysis and interpretation of data.</p><p id="par0065" class="elsevierStylePara elsevierViewall">Richa Aggarwal – conception and design of the study, analysis and interpretation of data, drafting the article.</p><p id="par0070" class="elsevierStylePara elsevierViewall">Puneet Khanna – conception and design of the study.</p><p id="par0075" class="elsevierStylePara elsevierViewall">Rakesh kumar – drafting the article or revising it critically for important intellectual content.</p><p id="par0080" class="elsevierStylePara elsevierViewall">Kapil Dev Soni – drafting the article or revising it critically for important intellectual.</p><p id="par0085" class="elsevierStylePara elsevierViewall">AnjanTrikha – revising it critically for important intellectual content and final approval of the version to be submitted.</p></span><span id="sec0010" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0010">Funding source</span><p id="par0090" class="elsevierStylePara elsevierViewall">None.</p></span><span id="sec0015" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0015">Conflict of interest</span><p id="par0095" class="elsevierStylePara elsevierViewall">The authors have no competing interests to declare.</p></span></span>" "textoCompletoSecciones" => array:1 [ "secciones" => array:4 [ 0 => array:2 [ "identificador" => "sec0005" "titulo" => "Authors’ contribution" ] 1 => array:2 [ "identificador" => "sec0010" "titulo" => "Funding source" ] 2 => array:2 [ "identificador" => "sec0015" "titulo" => "Conflict of interest" ] 3 => array:1 [ "titulo" => "References" ] ] ] "pdfFichero" => "main.pdf" "tienePdf" => true "apendice" => array:1 [ 0 => array:1 [ "seccion" => array:1 [ 0 => array:4 [ "apendice" => "<p id="par0105" class="elsevierStylePara elsevierViewall">The following are the supplementary data to this article:<elsevierMultimedia ident="upi0005"></elsevierMultimedia></p>" "etiqueta" => "Appendix A" "titulo" => "Supplementary data" "identificador" => "sec0025" ] ] ] ] "multimedia" => array:3 [ 0 => array:7 [ "identificador" => "fig0005" "etiqueta" => "Figure 1" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr1.jpeg" "Alto" => 1224 "Ancho" => 2091 "Tamanyo" => 264007 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">S/F ratio vs P/F ratio scatter plot. S/F ratio – SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>; P/F ratio – PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>. The line represents the best fit linear relationship SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>0.80(PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>)<span class="elsevierStyleHsp" style=""></span>+<span class="elsevierStyleHsp" style=""></span>59.8 (<span class="elsevierStyleItalic">p</span><span class="elsevierStyleHsp" style=""></span><<span class="elsevierStyleHsp" style=""></span>0.001).</p>" ] ] 1 => array:8 [ "identificador" => "tbl0005" "etiqueta" => "Table 1" "tipo" => "MULTIMEDIATABLA" "mostrarFloat" => true "mostrarDisplay" => false "detalles" => array:1 [ 0 => array:3 [ "identificador" => "at1" "detalle" => "Table " "rol" => "short" ] ] "tabla" => array:3 [ "leyenda" => "<p id="spar0015" class="elsevierStyleSimplePara elsevierViewall">HR – heart rate; RR – respiratory rate; SBP – systolic blood pressure; DBP – diastolic blood pressure; S/F ratio – SpO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>; P/F ratio – PaO<span class="elsevierStyleInf">2</span>/FiO<span class="elsevierStyleInf">2</span>; NRBM – non rebreathing mask; HFNC – high flow nasal cannula; NIV – non invasive ventilation.</p>" "tablatextoimagen" => array:1 [ 0 => array:1 [ "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">Variables \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">Invasive ventilation group (<span class="elsevierStyleItalic">n</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>19)Number (%)/Mean<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>SD/Median [Range] \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">Without invasive ventilation group (<span class="elsevierStyleItalic">n</span><span class="elsevierStyleHsp" style=""></span>=<span class="elsevierStyleHsp" style=""></span>41)Number (%)/Mean<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>SD/Median [Range] \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"><span class="elsevierStyleItalic">P</span>-value \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 \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">49.52<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>17.79 \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">52.56<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>12.99 \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.457 \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">Male/female \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 \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">26/15 \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.985 \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">HR (beats/min) \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">101.93<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>24.19 \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">88.26<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>16.37 \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.0132<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \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">SBP (mm/Hg) \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">124.7<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>22.5 \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">128.8<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>21.8 \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.54 \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">DBP (mm/Hg) \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">74.8<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>11.6 \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">72.1<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>10.6 \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.37 \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">RR (breaths/min) \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">33.47<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>6.08 \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">27.23<span class="elsevierStyleHsp" style=""></span>±<span class="elsevierStyleHsp" style=""></span>3.55 \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.0001<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \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">Accessory muscles use \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 (63) \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">5 (12.1) \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.0001<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \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 respiratory support \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="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \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="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.012<a class="elsevierStyleCrossRef" href="#tblfn0005">*</a> \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">Facemask \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">5 (26.3) \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">25 (60.9) \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="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \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">NRBM \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 (47.3) \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">14 (34.1) \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="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \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">HFNC/NIV \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">5 (26.3) \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 (4.88) \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="" valign="\n \t\t\t\t\ttop\n \t\t\t\t"> \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">S/F ratio \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 (80–250) \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">160 (71–333) \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.14 \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">P/F ratio \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 (41–442) \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">145 (36–528) \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="char" valign="\n \t\t\t\t\ttop\n \t\t\t\t">0.739 \t\t\t\t\t\t\n \t\t\t\t</td></tr></tbody></table> """ ] ] ] "notaPie" => array:1 [ 0 => array:3 [ "identificador" => "tblfn0005" "etiqueta" => "*" "nota" => "<p class="elsevierStyleNotepara" id="npar0005">Significant.</p>" ] ] ] "descripcion" => array:1 [ "en" => "<p id="spar0010" class="elsevierStyleSimplePara elsevierViewall">Comparison between patients who required invasive ventilation (ventilated group) and who did not require invasive ventilation (non ventilated group).</p>" ] ] 2 => array:5 [ "identificador" => "upi0005" "tipo" => "MULTIMEDIAECOMPONENTE" "mostrarFloat" => false "mostrarDisplay" => true "Ecomponente" => array:2 [ "fichero" => "mmc1.doc" "ficheroTamanyo" => 13496 ] ] ] "bibliografia" => array:2 [ "titulo" => "References" "seccion" => array:1 [ 0 => array:2 [ "identificador" => "bibs0015" "bibliografiaReferencia" => array:9 [ 0 => array:3 [ "identificador" => "bib0050" "etiqueta" => "1" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study" "autores" => array:1 [ 0 => array:2 [ "etal" => true "autores" => array:6 [ 0 => "F. Zhou" 1 => "T. Yu" 2 => "R. Du" 3 => "G. Fan" 4 => "Y. Liu" 5 => "Z. Liu" ] ] ] ] ] "host" => array:1 [ 0 => array:2 [ "doi" => "10.1016/S0140-6736(20)30566-3" "Revista" => array:6 [ "tituloSerie" => "Lancet" "fecha" => "2020" "volumen" => "395" "paginaInicial" => "1054" "paginaFinal" => "1062" "link" => array:1 [ 0 => array:2 [ "url" => "https://www.ncbi.nlm.nih.gov/pubmed/32171076" "web" => "Medline" ] ] ] ] ] ] ] ] 1 => array:3 [ "identificador" => "bib0055" "etiqueta" => "2" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "Misconceptions of pathophysiology of happy hypoxemia and implications for management of COVID-19" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:3 [ 0 => "M.J. Tobin" 1 => "A. Jubran" 2 => "F. 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| Year/Month | Html | Total | |
|---|---|---|---|
| 2024 October | 27 | 32 | 59 |
| 2024 September | 91 | 106 | 197 |
| 2024 August | 113 | 103 | 216 |
| 2024 July | 95 | 73 | 168 |
| 2024 June | 88 | 74 | 162 |
| 2024 May | 85 | 54 | 139 |
| 2024 April | 66 | 54 | 120 |
| 2024 March | 42 | 52 | 94 |
| 2024 February | 82 | 61 | 143 |
| 2024 January | 77 | 75 | 152 |
| 2023 December | 61 | 66 | 127 |
| 2023 November | 81 | 84 | 165 |
| 2023 October | 141 | 68 | 209 |
| 2023 September | 106 | 41 | 147 |
| 2023 August | 103 | 30 | 133 |
| 2023 July | 118 | 39 | 157 |
| 2023 June | 145 | 25 | 170 |
| 2023 May | 208 | 50 | 258 |
| 2023 April | 113 | 23 | 136 |
| 2023 March | 121 | 58 | 179 |
| 2023 February | 114 | 32 | 146 |
| 2023 January | 72 | 31 | 103 |
| 2022 December | 53 | 33 | 86 |
| 2022 November | 55 | 35 | 90 |
| 2022 October | 53 | 46 | 99 |
| 2022 July | 1 | 2 | 3 |
| 2022 June | 1 | 0 | 1 |
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