Correlation and validity of imputed PaO2/FiO2 and SpO2/FiO2 in patients with invasive mechanical ventilation at 2600m above sea level.

OBJECTIVE: To establish the correlation and validity between PaO2/FiO2 obtained on arterial gases versus noninvasive methods (linear, nonlinear, logarithmic imputation of PaO2/FiO2 and SpO2/FiO2) in patients under mechanical ventilation living at high altitude. DESIGN: Ambispective descriptive multicenter cohort study. SETTING: Two intensive care units (ICU) from Colombia at 2600m a.s.l. PATIENTS OR PARTICIPANTS: Consecutive critically ill patients older than 18 years with at least 24h of mechanical ventilation were included from June 2016 to June 2019. INTERVENTIONS: None. VARIABLES: Variables analyzed were demographic, physiological messures, laboratory findings, oxygenation index and clinical condition. Nonlinear, linear and logarithmic imputation formulas were used to calculate PaO2 from SpO2, and at the same time the SpO2/FiO2 by severe hypoxemia diagnosis. The intraclass correlation coefficient, area under the ROC curve, sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio were calculated. RESULTS: The correlation between PaO2/FiO2 obtained from arterial gases, PaO2/FiO2 derived from one of the proposed methods (linear, non-linear, and logarithmic formula), and SpO2/FiO2 measured by the intraclass correlation coefficient was high (greater than 0.77, p<0.001). The different imputation methods and SpO2/FiO2 have a similar diagnostic performance in patients with severe hypoxemia (PaO2/FiO2 <150). PaO2/FiO2 linear imputation AUC ROC 0,84 (IC 0.81-0.87, p<0.001), PaO2/FiO2 logarithmic imputation AUC ROC 0.84 (IC 0.80-0.87, p<0.001), PaO2/FiO2 non-linear imputation AUC ROC 0.82 (IC 0.79-0.85, p<0.001), SpO2/FiO2 oximetry AUC ROC 0.84 (IC 0.81-0.87, p<0.001). CONCLUSIONS: At high altitude, the SaO2/FiO2 ratio and the imputed PaO2/FiO2 ratio have similar diagnostic performance in patients with severe hypoxemia ventilated by various pathological conditions.

Prior influenza vaccine is not a risk factor for bacterial coinfection in patients admitted to the ICU due to severe influenza.

OBJECTIVE: To determine whether the prior usage of the flu vaccine is a risk factor for bacterial co-infection in patients with severe influenza. DESIGN: This was a retrospective observational cohort study of subjects admitted to the ICU. A propensity score matching, and logistic regression adjusted for potential confounders were carried out to evaluate the association between prior influenza vaccination and bacterial co-infection. SETTINGS: 184 ICUs in Spain due to severe influenza. PATIENTS: Patients included in the Spanish prospective flu registry. INTERVENTIONS: Flu vaccine prior to the hospital admission. RESULTS: A total of 4175 subjects were included in the study. 489 (11.7%) received the flu vaccine prior to develop influenza infection. Prior vaccinated patients were older 71 [61-78], and predominantly male 65.4%, with at least one comorbid condition 88.5%. Prior vaccination was not associated with bacterial co-infection in the logistic regression model (OR: 1.017; 95%CI 0.803-1.288; p=0.885). After matching, the average treatment effect of prior influenza vaccine on bacterial co-infection was not statistically significant when assessed by propensity score matching (p=0.87), nearest neighbor matching (p=0.59) and inverse probability weighting (p=0.99). CONCLUSIONS: No association was identified between prior influenza vaccine and bacterial coinfection in patients admitted to the ICU due to severe influenza. Post influenza vaccination studies are necessary to continue evaluating the possible benefits.

Impact of Aspergillus spp. isolation in the first 24 hours of admission in critically ill patients with severe influenza virus pneumonia.

OBJECTIVE: To determine the incidence and impact of Aspergillus spp. isolation (AI) on ICU mortality in critically ill patients with severe influenza pneumonia during the first 24h of admission. DESIGN: Secondary analysis of an observational and prospective cohort study. SETTING: ICUs voluntary participating in the Spanish severe Influenza pneumonia registry, between June 2009 and June 2019. PATIENTS: Consecutive patients admitted to the ICU with diagnosis of severe influenza pneumonia, confirmed by real-time polymerase chain reaction. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Incidence of AI in respiratory samples. Demographic variables, comorbidities, need for mechanical ventilation and the presence of shock according at admission. Acute Physiology and Chronic Health Evaluation II (APACHE II) scale calculated on ICU admission. RESULTS: 3702 patients were analyzed in this study. AI incidence was 1.13% (n=42). Hematological malignancies (OR 4.39, 95% CI 1.92-10.04); HIV (OR 3.83, 95% CI 1.08-13.63), and other immunosuppression situations (OR 4.87, 95% CI 1.99-11.87) were factors independently associated with the presence of Aspergillus spp. The automatic CHAID decision tree showed that hematologic disease with an incidence of 3.3% was the most closely AI related variable. Hematological disease (OR 2.62 95% CI 1.95-3.51), immunosuppression (OR 2.05 95% CI 1.46-2.88) and AI (OR 3.24, 95% CI 1.60-6.53) were variables independently associated with ICU mortality. CONCLUSIONS: Empirical antifungal treatment in our population may only be justified in immunocompromised patients. In moderate-high risk cases, active search for Aspergillus spp. should be implemented.

Correlation and validity of imputed PaO2/FiO2 and SpO2/FiO2 in patients with invasive mechanical ventilation at 2600m above sea level.

OBJECTIVE: To establish the correlation and validity between PaO2/FiO2 obtained on arterial gases versus noninvasive methods (linear, nonlinear, logarithmic imputation of PaO2/FiO2 and SpO2/FiO2) in patients under mechanical ventilation living at high altitude. DESIGN: Ambispective descriptive multicenter cohort study. SETTING: Two intensive care units (ICU) from Colombia at 2600m a.s.l. PATIENTS OR PARTICIPANTS: Consecutive critically ill patients older than 18 years with at least 24h of mechanical ventilation were included from June 2016 to June 2019. INTERVENTIONS: None. VARIABLES: Variables analyzed were demographic, physiological messures, laboratory findings, oxygenation index and clinical condition. Nonlinear, linear and logarithmic imputation formulas were used to calculate PaO2 from SpO2, and at the same time the SpO2/FiO2 by severe hypoxemia diagnosis. The intraclass correlation coefficient, area under the ROC curve, sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio were calculated. RESULTS: The correlation between PaO2/FiO2 obtained from arterial gases, PaO2/FiO2 derived from one of the proposed methods (linear, non-linear, and logarithmic formula), and SpO2/FiO2 measured by the intraclass correlation coefficient was high (greater than 0.77, p<0.001). The different imputation methods and SpO2/FiO2 have a similar diagnostic performance in patients with severe hypoxemia (PaO2/FiO2 <150). PaO2/FiO2 linear imputation AUC ROC 0,84 (IC 0.81-0.87, p<0.001), PaO2/FiO2 logarithmic imputation AUC ROC 0.84 (IC 0.80-0.87, p<0.001), PaO2/FiO2 non-linear imputation AUC ROC 0.82 (IC 0.79-0.85, p<0.001), SpO2/FiO2 oximetry AUC ROC 0.84 (IC 0.81-0.87, p<0.001). CONCLUSIONS: At high altitude, the SaO2/FiO2 ratio and the imputed PaO2/FiO2 ratio have similar diagnostic performance in patients with severe hypoxemia ventilated by various pathological conditions.

Prior influenza vaccine is not a risk factor for bacterial coinfection in patients admitted to the ICU due to severe influenza.

OBJECTIVE: To determine whether the prior usage of the flu vaccine is a risk factor for bacterial co-infection in patients with severe influenza. DESIGN: This was a retrospective observational cohort study of subjects admitted to the ICU. A propensity score matching, and logistic regression adjusted for potential confounders were carried out to evaluate the association between prior influenza vaccination and bacterial co-infection. SETTINGS: 184 ICUs in Spain due to severe influenza. PATIENTS: Patients included in the Spanish prospective flu registry. INTERVENTIONS: Flu vaccine prior to the hospital admission. RESULTS: A total of 4175 subjects were included in the study. 489 (11.7%) received the flu vaccine prior to develop influenza infection. Prior vaccinated patients were older 71 [61-78], and predominantly male 65.4%, with at least one comorbid condition 88.5%. Prior vaccination was not associated with bacterial co-infection in the logistic regression model (OR: 1.017; 95%CI 0.803-1.288; p=0.885). After matching, the average treatment effect of prior influenza vaccine on bacterial co-infection was not statistically significant when assessed by propensity score matching (p=0.87), nearest neighbor matching (p=0.59) and inverse probability weighting (p=0.99). CONCLUSIONS: No association was identified between prior influenza vaccine and bacterial coinfection in patients admitted to the ICU due to severe influenza. Post influenza vaccination studies are necessary to continue evaluating the possible benefits.

Relationship between acute kidney injury and serum procalcitonin (PCT) concentration in critically ill patients with influenza infection.

INTRODUCTION: Serum procalcitonin (PCT) concentration could be increased in patients with renal dysfunction in the absence of bacterial infection. OBJECTIVE: To determine the interactions among serum renal biomarkers of acute kidney injury (AKI) and serum PCT concentration, in patients admitted to the intensive care unit (ICU) due to lung influenza infection. DESIGN: Secondary analysis of a prospective multicentre observational study. SETTING: 148 Spanish ICUs. PATIENTS: ICU patients admitted with influenza infection without bacterial co-infection. Clinical, laboratory and hemodynamic variables were recorded. AKI was classified as AKI I or II based on creatinine (Cr) concentrations (≥1.60-2.50mg/dL and Cr≥2.51-3.99mg/dL, respectively). Patients with chronic renal disease, receiving renal replacement treatment or with Cr>4mg/dL were excluded. Spearman's correlation, simple and multiple linear regression analysis were performed. INTERVENTIONS: None. RESULTS: Out of 663 patients included in the study, 52 (8.2%) and 10 (1.6%) developed AKI I and II, respectively. Patients with AKI were significantly older, had more comorbid conditions and were more severally ill. PCT concentrations were higher in patients with AKI (2.62 [0.60-10.0]ng/mL vs. 0.40 [0.13-1.20]ng/mL, p=0.002). Weak correlations between Cr/PCT (rho=0.18) and Urea (U)/PCT (rho=0.19) were identified. Simple linear regression showed poor interaction between Cr/U and PCT concentrations (Cr R2=0.03 and U R2=0.018). Similar results were observed during multiple linear regression analysis (Cr R2=0.046 and U R2=0.013). CONCLUSIONS: Although PCT concentrations were slightly higher in patients with AKI, high PCT concentrations are not explained by AKI and could be warning sign of a potential bacterial infection.

Impact of Aspergillus spp. isolation in the first 24 hours of admission in critically ill patients with severe influenza virus pneumonia / Impacto del aislamiento de Aspergillus spp. en las primeras 24h de ingreso en pacientes críticos con neumonía grave por el virus influenza

Objective To determine the incidence and impact of Aspergillus spp. isolation (AI) on ICU mortality in critically ill patients with severe influenza pneumonia during the first 24h of admission. Design Secondary analysis of an observational and prospective cohort study. Setting ICUs voluntary participating in the Spanish severe Influenza pneumonia registry, between June 2009 and June 2019. Patients Consecutive patients admitted to the ICU with diagnosis of severe influenza pneumonia, confirmed by real-time polymerase chain reaction. Interventions None. Main variables of interest Incidence of AI in respiratory samples. Demographic variables, comorbidities, need for mechanical ventilation and the presence of shock according at admission. Acute Physiology and Chronic Health Evaluation II (APACHE II) scale calculated on ICU admission. Results 3702 patients were analyzed in this study. AI incidence was 1.13% (n=42). Hematological malignancies (OR 4.39, 95% CI 1.92–10.04); HIV (OR 3.83, 95% CI 1.08–13.63), and other immunosuppression situations (OR 4.87, 95% CI 1.99–11.87) were factors independently associated with the presence of Aspergillus spp. The automatic CHAID decision tree showed that hematologic disease with an incidence of 3.3% was the most closely AI related variable. Hematological disease (OR 2.62 95% CI 1.95–3.51), immunosuppression (OR 2.05 95% CI 1.46–2.88) and AI (OR 3.24, 95% CI 1.60–6.53) were variables independently associated with ICU mortality. Conclusions Empirical antifungal treatment in our population may only be justified in immunocompromised patients. In moderate-high risk cases, active search for Aspergillus spp. should be implemented (AU)

Objetivo Determinar la incidencia y el impacto sobre la mortalidad del aislamiento de Aspergillus spp. (AI) en paciente críticos con neumonía por influenza en las primeras 24h de ingreso. Diseño Análisis secundario de estudio de cohortes observacional y prospectivo. Ámbito Unidades de cuidados intensivos (UCI) participantes de forma voluntaria en el registro español de neumonía por influenza grave, desde junio de 2009 hasta junio de 2019. Pacientes Pacientes consecutivos con diagnóstico de neumonía grave por influenza, confirmado por prueba de reacción en cadena de la polimerasa. Intervenciones Ninguna. Variables principales Incidencia de AI. Variables demográficas, comorbilidades, necesidad de ventilación mecánica y presencia de shock al ingreso. APACHE II. Resultados Se analizaron 3.702 pacientes. La incidencia de AI fue del 1,13% (n=42). Las neoplasias hematológicas (OR: 4,39; IC 95%: 1,92-10,04); VIH (OR: 3,83; IC 95%: 1,08-13,63) y otras situaciones de inmunosupresión (OR: 4,87; IC 95%: 1,99-11,87) fueron variables que se asociaron de forma independiente con AI. El árbol de decisión de CHAID mostró que la variable neoplasias hematológicas era la más relacionada con la variable Aspergillus spp. con una incidencia del 3,3%. Neoplasias hematológicas (OR: 2,62; IC 95%: 1,95-3,51), inmunosupresión (OR: 2,05; IC 95%: 1,46-2,88) y AI (OR: 3,24; IC 95%: 1,60-6,53) se asociaron de forma independiente con mayor mortalidad en la UCI. Conclusiones El tratamiento antifúngico empírico en nuestra población estaría justificado en los pacientes con inmunosupresión. En los pacientes con riesgo moderado-grave, la búsqueda activa de Aspergillus spp. debería implementarse (AU)

Prior influenza vaccine is not a risk factor for bacterial coinfection in patients admitted to the ICU due to severe influenza / La vacuna previa contra la influenza no es un factor de riesgo de coinfección bacteriana en pacientes ingresados en la UCI por influenza severa

Objective To determine whether the prior usage of the flu vaccine is a risk factor for bacterial co-infection in patients with severe influenza. Design This was a retrospective observational cohort study of subjects admitted to the ICU. A propensity score matching, and logistic regression adjusted for potential confounders were carried out to evaluate the association between prior influenza vaccination and bacterial co-infection. Settings 184 ICUs in Spain due to severe influenza. Patients Patients included in the Spanish prospective flu registry. Interventions Flu vaccine prior to the hospital admission. Results A total of 4175 subjects were included in the study. 489 (11.7%) received the flu vaccine prior to develop influenza infection. Prior vaccinated patients were older 71 [61–78], and predominantly male 65.4%, with at least one comorbid condition 88.5%. Prior vaccination was not associated with bacterial co-infection in the logistic regression model (OR: 1.017; 95%CI 0.803–1.288; p=0.885). After matching, the average treatment effect of prior influenza vaccine on bacterial co-infection was not statistically significant when assessed by propensity score matching (p=0.87), nearest neighbor matching (p=0.59) and inverse probability weighting (p=0.99). Conclusions No association was identified between prior influenza vaccine and bacterial coinfection in patients admitted to the ICU due to severe influenza. Post influenza vaccination studies are necessary to continue evaluating the possible benefits (AU)

Objetivo Determinar si el uso previo de la vacuna antigripal es un factor de riesgo para coinfección bacteriana en pacientes con influenza grave. Diseño Este fue un estudio de cohorte observacional retrospectivo de sujetos ingresados en la UCI. Se realizó un emparejamiento por puntuación de propensión y una regresión logística ajustada para posibles factores de confusión para evaluar la asociación entre el antecedente de vacunación contra la gripe y la coinfección bacteriana. Ámbito Ciento ochenta y cuatro ingresos en UCI españolas por gripe grave. Pacientes Pacientes incluidos en el registro prospectivo español de gripe. Intervenciones Vacuna antigripal previa al ingreso hospitalario. Resultados Se incluyó en el estudio un total de 4.175 sujetos. Recibieron la vacuna contra la influenza antes de desarrollar la infección por influenza 489 (11,7%). Los pacientes previamente vacunados eran mayores de 71 años (RIC 61-78), predominantemente varones (65,4%) y con al menos una condición comórbida (88,5%). La vacunación previa no se asoció con la coinfección bacteriana en el modelo de regresión logística (OR: 1,017; IC95% 0,803-1,288; p=0,885). Después del emparejamiento, el efecto promedio del tratamiento del antecedente de vacuna contra la influenza sobre la coinfección bacteriana no fue estadísticamente significativo cuando se evaluó mediante el emparejamiento por puntuación de propensión (p=0,87), por emparejamiento del vecino más cercano (p=0,59) y mediante la ponderación de probabilidad inversa (p=0,99). Conclusiones No se identificó asociación entre el antecedente de vacuna antigripal y coinfección bacteriana en pacientes ingresados en UCI por influenza severa. Más estudios para evaluar los efectos de la vacunación contra la gripe son necesarios para continuar evaluando los posibles beneficios (AU)

Correlation and validity of imputed PaO2/FiO2 and SpO2/FiO2 in patients with invasive mechanical ventilation at 2600m above sea level / Correlación y validez de la PaO2/FiO2 y SpO2/FiO2 imputadas en pacientes con ventilación mecánica invasiva a 2.600 metros sobre el nivel del mar

Objective To establish the correlation and validity between PaO2/FiO2 obtained on arterial gases versus noninvasive methods (linear, nonlinear, logarithmic imputation of PaO2/FiO2 and SpO2/FiO2) in patients under mechanical ventilation living at high altitude. Design Ambispective descriptive multicenter cohort study. Setting Two intensive care units (ICU) from Colombia at 2600m a.s.l. Patients or participants Consecutive critically ill patients older than 18 years with at least 24h of mechanical ventilation were included from June 2016 to June 2019. Interventions None. Variables Variables analyzed were demographic, physiological messures, laboratory findings, oxygenation index and clinical condition. Nonlinear, linear and logarithmic imputation formulas were used to calculate PaO2 from SpO2, and at the same time the SpO2/FiO2 by severe hypoxemia diagnosis. The intraclass correlation coefficient, area under the ROC curve, sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio were calculated. Results The correlation between PaO2/FiO2 obtained from arterial gases, PaO2/FiO2 derived from one of the proposed methods (linear, non-linear, and logarithmic formula), and SpO2/FiO2 measured by the intraclass correlation coefficient was high (greater than 0.77, p<0.001). The different imputation methods and SpO2/FiO2 have a similar diagnostic performance in patients with severe hypoxemia (PaO2/FiO2 <150). PaO2/FiO2 linear imputation AUC ROC 0,84 (IC 0.81–0.87, p<0.001), PaO2/FiO2 logarithmic imputation AUC ROC 0.84 (IC 0.80–0.87, p<0.001), PaO2/FiO2 non-linear imputation AUC ROC 0.82 (IC 0.79–0.85, p<0.001), SpO2/FiO2 oximetry AUC ROC 0.84 (IC 0.81–0.87, p<0.001). Conclusions At high altitude, the SaO2/FiO2 ratio and the imputed PaO2/FiO2 ratio have similar diagnostic performance in patients with severe hypoxemia ventilated by various pathological conditions (AU)

Objetivo Establecer la correlación y validez entre PaO2/FiO2 obtenida en gases arteriales versus métodos no invasivos (imputación lineal, no lineal, logarítmica de PaO2/FiO2 y SpO2/FiO2) en pacientes bajo ventilación mecánica que viven en altitudes elevadas. Diseño Estudio de cohorte multicéntrico descriptivo ambispectivo Ámbito Dos unidades de cuidados intensivos de Colombia a 2.600 m s.n.m. Pacientes o participantes Se incluyeron pacientes consecutivos en estado crítico mayores de 18 años con al menos 24h de ventilación mecánica desde junio de 2016 a junio de 2019. Intervenciones Ninguna. Variables Las variables analizadas fueron demográficas, fisiológicas, hallazgos de laboratorio, índice de oxigenación y estado clínico. Se utilizaron fórmulas de imputación no lineales, lineales y logarítmicas para calcular la PaO2 a partir de la SpO2, y al mismo tiempo la SpO2/FiO2 mediante el diagnóstico de hipoxemia severa. Se calculó el coeficiente de correlación intraclase, el área bajo la curva ROC, la sensibilidad, la especificidad, el valor predictivo positivo, el valor predictivo negativo, la razón de verosimilitud positiva y negativa. Resultados La correlación entre PaO2/FiO2 obtenida a partir de gases arteriales, PaO2/FiO2 derivada de uno de los métodos propuestos (fórmula lineal, no lineal y logarítmica) y SpO2/FiO2 medida por el coeficiente de correlación intraclase fue alta (mayor a 0,77, p<0,001). Los diferentes métodos de imputación y SpO2/FiO2 tienen un rendimiento diagnóstico similar en pacientes con hipoxemia severa (PaO2/FiO2<150). PaO2/FiO2 imputación lineal AUC ROC 0,84 (IC 0,81-0,87; p<0,001), PaO2/FiO2 imputación logarítmica AUC ROC 0,84 (IC 0,80-0,87; p<0,001), PaO2/Imputación no lineal de FiO2 AUC ROC 0,82 (IC 0,79-0,85; p<0,001), oximetría de SpO2/FiO2 AUC ROC 0,84 (IC 0,81-0,87; p<0,001). Conclusiones A gran altitud, el cociente SaO2/FiO2 y el cociente PaO2/FiO2 (AU)

[Use of and verification with biological indicators in sterilizers belonging to dentistry surgeons from San Luis Potosi, Mexico]. / Uso y verificación con indicadores biológicos en esterilizadores de cirujanos dentistas de San Luis Potosí, México.

OBJECTIVE: To assess the utilization of sterilizing equipment used by dentists, and verification of sterilization using biological indicators. MATERIAL AND METHODS: A cross-sectional study was conducted in 1999-2000, among 130 (65%) dentists having sterilizing equipment, at Facultad de Estomatología, Universidad Autónoma de San Luis Potosí and Colegio Dental Potosino. Biological indicators for sterilization containing Bacillus subtilis and Bacillus stearothermophilus were used. RESULTS: Thirty autoclaves and 100 dry-heat sterilizers were evaluated: 23 (17.7%) of them showed bacterial growth. Twenty-one (16.1%) dentists already were using biological indicators to verify their sterilizing equipment. Both sterilization methods were found to allow bacterial growth with similar frequencies (p = > 0.66). CONCLUSIONS: Few dentists verify the quality of sterilization process through biological indicators; bacterial growth and failure of sterilization were evidenced.