Clinical Characteristics and Outcomes Are Similar in ARDS Diagnosed by Oxygen Saturation/Fio2 Ratio Compared With Pao2/Fio2 Ratio

Use of volume controlled vs. pressure controlled volume guaranteed ventilation in elderly patients undergoing laparoscopic surgery with laryngeal mask airway

Background

The peak inspiratory pressure (PIP) is crucial in mechanical ventilation with supraglottic airway device (SAD). Pressure-controlled ventilation volume-guaranteed (PCV-VG), delivering a preset tidal volume with the lowest required airway pressure, is being increasingly used during general anesthesia. In this study, we compared respiratory mechanics and circulatory parameters between volume-controlled ventilation (VCV) and PCV-VG in elderly patients undergoing laparoscopic surgery using the laryngeal mask airway supreme (LMA).

Methods

Eighty participants scheduled for laparoscopic surgery were enrolled in this prospective, randomized clinical trial. The participants were randomly assigned to receive VCV or PCV-VG. PIP, dynamic compliance (Cdyn) and mean inspiratory pressure (Pmean) were recorded at 5 min after induction of anesthesia (T1), 5 min after pneumoperitoneum(T2), 30 and 60 min after pneumoperitoneum (T3 and T4). Data including other respiratory variables, hemodynamic variables, and arterial blood gases were also collected. The difference in PIP between VCV and PCV-VG was assessed as the primary outcome.

Results

PIP was significantly lower at T2, T3, and T4 in both groups compared with T1 (all P <  0.0001), and it was significantly lower in the PCV-VG group than the VCV group at T2, T3, and T4 (all P <  0.001). Cydn was decreased at T2, T3, and T4 in two groups compared with T1 (all P <  0.0001), but it was higher in PCV-VG group than in VCV group at T2, T3, and T4 (all P <  0.0001). There were on statistically significant differences were found between the groups for other respiratory and hemodynamic variables.

Conclusion

In elderly patients who underwent laparoscopic surgery using an LMA, PCV-VG was superior to VCV in its ability to provide ventilation with lower peak inspiratory pressure and greater dynamic compliance.

A Case-Control Study of Prone Positioning in Awake and Nonintubated Hospitalized Coronavirus Disease 2019 Patients

Supplemental Digital Content is available in the text.

To determine the association between prone positioning in nonintubated patients with coronavirus disease 2019 and frequency of invasive mechanical ventilation or inhospital mortality.

Angiopoietin-2 outperforms other endothelial biomarkers associated with severe acute kidney injury in patients with severe sepsis and respiratory failure

BACKGROUND

Endothelial dysfunction and injury is a major pathophysiologic feature of sepsis. Sepsis is also the most frequent cause of acute kidney injury (AKI) in critically ill patients. Though most studies of AKI in sepsis have focused on tubular epithelial injury, the role of endothelial dysfunction and injury is less well studied. The goal of this study was first to investigate whether endothelial dysfunction and injury biomarkers were associated with severe AKI in sepsis patients. The second goal was to determine the best performing biomarker for severe AKI and whether this biomarker was associated with severe AKI across different etiologies of sepsis and clinical outcomes.

METHODS

We studied adults with severe sepsis and acute respiratory failure (ARF) enrolled in the prospective observational Validating Acute Lung Injury markers for Diagnosis (VALID) study. Plasma endothelial dysfunction and injury biomarkers, including angiopoietin-2, soluble vascular endothelial cadherin (sVE-cadherin), endocan and syndecan-1, were measured at study enrollment. Primary analysis focused on the association between endothelial biomarker levels with severe AKI (defined as Kidney Disease: Improving Global Outcomes [KDIGO] AKI stage 2 or 3), other organ dysfunctions (defined by Brussels organ failure scores), and comparison of pulmonary versus non-pulmonary sepsis.

RESULTS

Among 228 sepsis patients enrolled, 141 developed severe AKI. Plasma levels of angiopoietin-2, endocan, sVE-cadherin, and syndecan-1 were significantly higher in sepsis patients with severe AKI compared to those without severe AKI. Among four endothelial biomarkers, only angiopoietin-2 was independently associated with severe AKI (odds ratio 6.07 per log increase, 95% CI 2.34-15.78, p < 0.001). Plasma angiopoietin-2 levels by quartile were significantly higher in sepsis patients with hepatic, coagulation, and circulatory failure. Plasma angiopoietin-2 levels were also significantly higher in patients with non-pulmonary sepsis compared to subjects with pulmonary sepsis.

CONCLUSION

Among four biomarkers of endothelial dysfunction and injury, angiopoietin-2 had the most robust independent association with development of severe AKI in patients with severe sepsis and ARF. Plasma angiopoietin-2 levels were also associated with other organ dysfunctions, non-pulmonary sepsis, and death. These findings highlight the importance of early endothelial dysfunction and injury in the pathogenesis of sepsis-induced AKI.

The clinical characteristics and prognosis of COVID-19 patients with comorbidities: a retrospective analysis of the infection peak in Wuhan

Background

This study aims to determine the clinical characteristics and prognosis of COVID-19 patients with comorbidities and to identify survival factors.

Methods

A retrospective study was conducted in Wuhan, China, between February 8, 2020, and March 9, 2020. Based on underlying diseases, patients were assigned to either the comorbidity group or the non-comorbidity group. The clinical characteristics and outcomes of COVID-19 were analyzed and a Kaplan-Meier survival analysis was used to evaluate the prognosis predictive value of each comorbidity.

Results

During the study period, 278 COVID-19 patients were enrolled, 175 (62.95%) were assigned to the comorbidity group, and 103 (37.05%) to the non-comorbidity group. Of the patients in the comorbidity group, 34.86% were classified as critical. Further, patients in the comorbidity group had lower lymphocyte cell counts, and higher concentrations of D-dimer, high sensitivity C-reactive protein, interleukin 6, and serum ferritin as well as higher critical illness severity scores than patients in the non-comorbidity group (P<0.05). Patients in the comorbidity group also had higher mortality, acute respiratory distress syndrome, and ventilation treatment rates than patients in the non-comorbidity group (P<0.05). The length of hospital stay was longer in the comorbidity group than in the non-comorbidity group (P<0.05). The most common underlying diseases included hypertension (40.65%), diabetes mellitus (20.5%), and cardiovascular disease (19.42%). Patients with comorbidities were more likely to develop cardiovascular sequelae associated with COVID-19, shock, acute kidney injury, and multiple organ dysfunction syndrome (30.86% vs. 12.62%, P=0.001; 18.86% vs. 8.74%, P=0.023; 24.57% vs. 11.65%, P=0.009; 33.71% vs. 14.56%, P=0.000, respectively). In the Kaplan-Meier survival analysis, older patients (¡Ý65 years) (log-rank test: χ²=4.202, P=0.040) and patients with chronic obstructive pulmonary disease (COPD) (log-rank test: χ²=4.839, P=0.028) or diabetes mellitus (log-rank test: χ²=4.377, P=0.036) had shorter survival than those without comorbidities.

Conclusions

Patients with comorbidities were more severely affected and had a higher mortality rate. Age, COPD and diabetes mellitus were the main factors affecting the survival of patients.

Acute respiratory distress syndrome (ARDS) as an adverse event following immunization: Case definition & guidelines for data collection, analysis, and presentation of immunization safety data

This is a Brighton Collaboration Case Definition of the term “Acute Respiratory Distress Syndrome – ARDS” to be utilized in the evaluation of adverse events following immunization. The Case Definition was developed by a group of experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of vaccines for SARS-CoV-2 vaccines and other emerging pathogens. The case definition format of the Brighton Collaboration was followed to develop a consensus definition and defined levels of certainty, after an exhaustive review of the literature and expert consultation. The document underwent peer review by the Brighton Collaboration Network and by selected Expert Reviewers prior to submission. The comments of the reviewers were taken into consideration and edits incorporated in this final manuscript.

Severity of illness scores at presentation predict ICU admission and mortality in COVID-19

Background

The COVID-19 pandemic has overwhelmed hospital systems in multiple countries and necessitated caring for patients in atypical healthcare settings. The goal of this study was to ascertain if the conventional critical care severity scores qSOFA, SOFA, APACHE-II, and SAPS-II could predict which patients admitted to the hospital from an emergency department would eventually require intensive care.

Methods

This single-center, retrospective cohort study enrolled patients admitted to Vanderbilt University Hospital from the emergency room with symptomatic, confirmed COVID-19 infection between March 8, 2020 through May 15, 2020. Clinical phenotyping was performed by chart abstraction, and the correlation of the qSOFA, SOFA, APACHE-II, and SAPS-II scores for the primary endpoint of ICU admission and secondary endpoint of in-hospital mortality was evaluated.

Results

During the study period, 128 patients were admitted to Vanderbilt University Hospital from the emergency room with COVID-19. Of these, 39 patients eventually required intensive care; the remaining 89 were discharged from the medical ward. All severity of illness scores demonstrated at least moderate ability to identify patients who would die or require ICU admission. Of the three severity of illness scores assessed, the APACHE-II score performed best with an AUC of 0.851 (95% CI: 0.786 to 0.917) for identifying patient that would require ICU admission. No patient with an APACHE-II score at the time of presentation less than 8 or qSOFA of 0 required intensive care unit (ICU) admission. All patients with an APACHE-II score less than 10 or qSOFA score of 0 survived to hospital discharge.

Conclusions

The APACHE-II score accurately predicts the eventual need for ICU admission. This may allow for risk-stratification of patients safe to treat in alternative health care settings and prognostic enrichment to accelerate clinical trials of COVID-19 therapies.

Utility of SpO2/FiO2 ratio for acute hypoxemic respiratory failure with bilateral opacities in the ICU

Acute hypoxemic respiratory failure (AHRF) with bilateral opacities causes fatalities in the intensive care unit (ICU). It is often difficult to identify the causes of AHRF at the time of admission. The SpO2 to FiO2 (S/F) ratio has been recently used as a non-invasive and alternative marker of the PaO2/FiO2 (P/F) ratio in acute respiratory failure. This retrospective cohort study was conducted from October 2010 to March 2019 at the Showa University Hospital, Tokyo, Japan. We enrolled 94 AHRF patients who had bilateral opacities and received mechanical ventilation in ICU to investigate their prognostic markers including S/F ratio. Significant differences were observed for APACHE II, S/F ratio, PaO2/FiO2 (P/F) ratio, and ventilator-free-days at day 28 for ICU mortality, and for age, S/F ratio, P/F ratio, duration of mechanical ventilation, and ventilator-free days at day 28 for hospital mortality. Multivariate logistic regression analysis showed that the S/F ratio was significantly and independently associated with the risk of death during in ICU (p = 0.003) and hospitalization (p = 0.002). The area under the receiver operating characteristic curves (AUC) based on the S/F ratio were significantly greater than those based on simplified acute physiology score (SAPS) II and sequential organ failure assessment (SOFA) for ICU mortality (0.785 in S/F ratio vs. 0.575 in SAPS II, p = 0.012; 0.785 in S/F ratio vs 0.594 in SOFA, p = 0.021) and for hospital mortality (0.701 in S/F ratio vs. 0.502 in SAPS II, p = 0.012; 0.701 in S/F ratio vs. 0.503 in SOFA, p = 0.005). In the subanalysis for bacterial pneumonia and interstitial lung disease groups, the AUC based on the S/F ratio was the greatest among all prognostic markers, including APACHE II, SAPS II, and SOFA. The S/F ratio may be a useful and noninvasive predictive prognostic marker for acute hypoxemic respiratory failure with bilateral opacities in the ICU.

Use of Machine Learning to Screen for Acute Respiratory Distress Syndrome Using Raw Ventilator Waveform Data

To develop and characterize a machine learning algorithm to discriminate acute respiratory distress syndrome from other causes of respiratory failure using only ventilator waveform data.

Design

Retrospective, observational cohort study.

Setting

Academic medical center ICU.

Patients

Adults admitted to the ICU requiring invasive mechanical ventilation, including 50 patients with acute respiratory distress syndrome and 50 patients with primary indications for mechanical ventilation other than hypoxemic respiratory failure.

Interventions

None.

Measurements and Main Results

Pressure and flow time series data from mechanical ventilation during the first 24-hours after meeting acute respiratory distress syndrome criteria (or first 24-hr of mechanical ventilation for non-acute respiratory distress syndrome patients) were processed to extract nine physiologic features. A random forest machine learning algorithm was trained to discriminate between the patients with and without acute respiratory distress syndrome. Model performance was assessed using the area under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, and negative predictive value. Analyses examined performance when the model was trained using data from the first 24 hours and tested using withheld data from either the first 24 hours (24/24 model) or 6 hours (24/6 model). Area under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, and negative predictive value were 0.88, 0.90, 0.71, 0.77, and 0.90 (24/24); and 0.89, 0.90, 0.75, 0.83, and 0.83 (24/6).

Conclusions

Use of machine learning and physiologic information derived from raw ventilator waveform data may enable acute respiratory distress syndrome screening at early time points after intubation. This approach, combined with traditional diagnostic criteria, could improve timely acute respiratory distress syndrome recognition and enable automated clinical decision support, especially in settings with limited availability of conventional diagnostic tests and electronic health records.

Personalized Medicine for the Management of RDS in Preterm Neonates

Continuous positive airway pressure and surfactant represent the first- and second-line treatment for respiratory distress syndrome in preterm neonates, as European and American guidelines, since 2013 and 2014, respectively, started to recommend surfactant replacement only when continuous positive airway pressure fails. These recommendations, however, are not personalized to the individual physiopathology. Simple clinical algorithms may have improved the diffusion of neonatal care, but complex medical issues can hardly be addressed with simple solutions. The treatment of respiratory distress syndrome is a complex matter and can be only optimized with personalization. We performed a review of tools to individualize the management of respiratory distress syndrome based on physiopathology and actual patients' need, according to precision medicine principles. Advanced oxygenation metrics, lung ultrasound, electrical impedance tomography, and both quantitative and qualitative surfactant assays were examined. When these techniques were investigated with diagnostic accuracy studies, reliability measures have been meta-analysed. Amongst all these tools, quantitative lung ultrasound seems the more developed for the widespread use and has a higher diagnostic accuracy (meta-analytical AUC = 0.952 [95% CI: 0.951-0.953]). Surfactant adsorption (AUC = 0.840 [95% CI: 0.824-0.856]) and stable microbubble test (AUC = 0.800 [95% CI: 0.788-0.812]) also have good reliability, but need further industrial development. We advocate for a more accurate characterization and a personalized approach of respiratory distress syndrome. With the above-described currently available tools, it should be possible to personalize the treatment of respiratory distress syndrome according to physiopathol-ogy.

Patient Trajectories Among Persons Hospitalized for COVID-19 : A Cohort Study

BACKGROUND

Risk factors for progression of coronavirus disease 2019 (COVID-19) to severe disease or death are underexplored in U.S. cohorts.

OBJECTIVE

To determine the factors on hospital admission that are predictive of severe disease or death from COVID-19.

DESIGN

Retrospective cohort analysis.

SETTING

Five hospitals in the Maryland and Washington, DC, area.

PATIENTS

832 consecutive COVID-19 admissions from 4 March to 24 April 2020, with follow-up through 27 June 2020.

MEASUREMENTS

Patient trajectories and outcomes, categorized by using the World Health Organization COVID-19 disease severity scale. Primary outcomes were death and a composite of severe disease or death.

RESULTS

Median patient age was 64 years (range, 1 to 108 years); 47% were women, 40% were Black, 16% were Latinx, and 21% were nursing home residents. Among all patients, 131 (16%) died and 694 (83%) were discharged (523 [63%] had mild to moderate disease and 171 [20%] had severe disease). Of deaths, 66 (50%) were nursing home residents. Of 787 patients admitted with mild to moderate disease, 302 (38%) progressed to severe disease or death: 181 (60%) by day 2 and 238 (79%) by day 4. Patients had markedly different probabilities of disease progression on the basis of age, nursing home residence, comorbid conditions, obesity, respiratory symptoms, respiratory rate, fever, absolute lymphocyte count, hypoalbuminemia, troponin level, and C-reactive protein level and the interactions among these factors. Using only factors present on admission, a model to predict in-hospital disease progression had an area under the curve of 0.85, 0.79, and 0.79 at days 2, 4, and 7, respectively.

LIMITATION

The study was done in a single health care system.

CONCLUSION

A combination of demographic and clinical variables is strongly associated with severe COVID-19 disease or death and their early onset. The COVID-19 Inpatient Risk Calculator (CIRC), using factors present on admission, can inform clinical and resource allocation decisions.

PRIMARY FUNDING SOURCE

Hopkins inHealth and COVID-19 Administrative Supplement for the HHS Region 3 Treatment Center from the Office of the Assistant Secretary for Preparedness and Response.

[All Roads Lead to Rome: Results of Non-Invasive Respiratory Therapies Applied in a Tertiary-Care Hospital Without an Intermediate Care Unit During the COVID-19 Pandemic]

Introduction

Non-invasive respiratory therapies (NRT) were widely used in the first wave of the COVID-19 pandemic in different settings, depending on availability. The objective of our study was to present 90-day survival and associated factors in patients treated with NRT in a tertiary hospital without an Intermediate Respiratory Care Unit. The secondary objective was to compare the outcomes of the different therapies.

Methods

Observational study of patients treated with NRT outside of an intensive care or intermediate respiratory care unit setting, diagnosed with COVID-19 and acute respiratory distress syndrome by radiological criteria and SpO2/FiO2 ratio. A multivariate logistic regression model was developed to determine independently associated variables, and the outcomes of high flow nasal cannula and continuous positive airway pressure were compared.

Results

In total, 107 patients were treated and 85 (79.4%) survived at 90 days. Before starting NRT, the mean SpO2/FiO2 ratio was 119.8 ± 59.4. A higher SOFA score was significantly associated with mortality (OR 2,09; 95% CI 1.34-3.27), while self-pronation was a protective factor (OR 0.23; 95% CI 0.06-0.91). High flow nasal cannula was used in 63 subjects (58.9%), and continuous positive airway pressure in 41 (38.3%), with no differences between them.

Conclusion

Approximately 4 out of 5 patients treated with NRT survived to 90 days, and no significant differences were found between high flow nasal cannula and continuous positive airway pressure.

Corticosteroid treatment in severe COVID-19 patients with acute respiratory distress syndrome

BACKGROUNDCorticosteroids are widely used in patients with COVID 19, although their benefit-to-risk ratio remains controversial.METHODSPatients with severe COVID-19-related acute respiratory distress syndrome (ARDS) were included from December 29, 2019 to March 16, 2020 in 5 tertiary Chinese hospitals. Cox proportional hazards and competing risks analyses were conducted to analyze the impact of corticosteroids on mortality and SARS-CoV-2 RNA clearance, respectively. We performed a propensity score (PS) matching analysis to control confounding factors.RESULTSOf 774 eligible patients, 409 patients received corticosteroids, with a median time from hospitalization to starting corticosteroids of 1.0 day (IQR 0.0-3.0 days) . As compared with usual care, treatment with corticosteroids was associated with increased rate of myocardial (15.6% vs. 10.4%, P = 0.041) and liver injury (18.3% vs. 9.9%, P = 0.001), of shock (22.0% vs. 12.6%, P < 0.001), of need for mechanical ventilation (38.1% vs. 19.5%, P < 0.001), and increased rate of 28-day all-cause mortality (44.3% vs. 31.0%, P < 0.001). After PS matching, corticosteroid therapy was associated with 28-day mortality (adjusted HR 1.46, 95% CI 1.01-2.13, P = 0.045). High dose (>200 mg) and early initiation (≤3 days from hospitalization) of corticosteroid therapy were associated with a higher 28-day mortality rate. Corticosteroid use was also associated with a delay in SARS-CoV-2 coronavirus RNA clearance in the competing risk analysis (subhazard ratio 1.59, 95% CI 1.17-2.15, P = 0.003).CONCLUSIONAdministration of corticosteroids in severe COVID-19-related ARDS is associated with increased 28-day mortality and delayed SARS-CoV-2 coronavirus RNA clearance after adjustment for time-varying confounders.FUNDINGNone.

Clinically applicable approach for predicting mechanical ventilation in patients with COVID-19

Background

Patients with coronavirus disease 2019 (COVID-19) requiring mechanical ventilation have high mortality and resource utilisation. The ability to predict which patients may require mechanical ventilation allows increased acuity of care and targeted interventions to potentially mitigate deterioration.

Methods

We included hospitalised patients with COVID-19 in this single-centre retrospective observational study. Our primary outcome was mechanical ventilation or death within 24 h. As clinical decompensation is more recognisable, but less modifiable, as the prediction window shrinks, we also assessed 4, 8, and 48 h prediction windows. Model features included demographic information, laboratory results, comorbidities, medication administration, and vital signs. We created a Random Forest model, and assessed performance using 10-fold cross-validation. The model was compared with models derived from generalised estimating equations using discrimination.

Results

Ninety-three (23%) of 398 patients required mechanical ventilation or died within 14 days of admission. The Random Forest model predicted pending mechanical ventilation with good discrimination (C-statistic=0.858; 95% confidence interval, 0.841–0.874), which is comparable with the discrimination of the generalised estimating equation regression. Vitals sign data including SpO₂/FiO₂ ratio (Random Forest Feature Importance Z-score=8.56), ventilatory frequency (5.97), and heart rate (5.87) had the highest predictive utility. In our highest-risk cohort, the number of patients needed to identify a single new case was 3.2, and for our second quintile it was 5.0.

Conclusion

Machine learning techniques can be leveraged to improve the ability to predict which patients with COVID-19 are likely to require mechanical ventilation, identifying unrecognised bellwethers and providing insight into the constellation of accompanying signs of respiratory failure in COVID-19.

Early neuromuscular blocking agents for adults with acute respiratory distress syndrome: a systematic review, meta-analysis and meta-regression

OBJECTIVE

To determine whether neuromuscular blocking agents (NMBAs) can decrease the mortality of patients with acute respiratory distress syndrome (ARDS) and improve their clinical outcomes.

DESIGN

Systematic review, meta-analysis and meta-regression.

DATA SOURCES

PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov.

METHODS

Randomised controlled trials (RCTs) comparing the treatment effect of NMBAs with that of placebo (or traditional treatment) in patients with ARDS were carefully selected. The primary outcome was 90-day mortality. The secondary outcomes were 21-28 days mortality, NMBA-related complications (barotrauma, pneumothorax and intensive care unit (ICU)-acquired muscle weakness), days free of ventilation and days not in the ICU by day 28, Medical Research Council score, Acute Physiology and Chronic Health Evaluation II score and arterial oxygen tension (PaO₂)/fractional inspired oxygen (FiO₂) (at 48 hours and 72 hours). Random-effects meta-regression was used to explore models involving potential moderators. Trial sequential analysis was performed to estimate the cumulative effect on mortality across RCTs.

RESULTS

NMBAs were not associated with reduced 90-day mortality (risk ratio (RR) 0.85; 95% CI 0.66 to 1.09; p=0.20). However, they decreased the 21-28 days mortality (RR 0.71; 95% CI 0.53 to 0.96; p=0.02) and the rates of pneumothorax (RR 0.46; 95% CI 0.28 to 0.77; p=0.003) and barotrauma (RR 0.56; 95% CI 0.37 to 0.86; p=0.008). In addition, NMBAs increased PaO₂/FiO₂ at 48 hours (mean difference (MD) 18.91; 95% CI 4.29 to 33.53; p=0.01) and 72 hours (MD 12.27; 95% CI 4.65 to 19.89; p=0.002). Meta-regression revealed an association between sample size (p=0.042) and short-term mortality. Publication year (p=0.050), sedation strategy (p=0.047) and sample size (p=0.046) were independently associated with PaO₂/FiO₂ at 48 hours.

CONCLUSIONS

In summary, the results suggested that use of NMBAs might reduce 21-28 days mortality, NMBA-related complications and oxygenation. However, NMBAs did not reduce the 90-day mortality of patients with ARDS, which contradicts a previous meta-analysis.

PROSPERO REGISTRATION NUMBER

CRD42019139440.

Awake prone positioning of hypoxaemic patients with COVID-19: protocol for a randomised controlled open-label superiority meta-trial

INTRODUCTION

Prone positioning (PP) is an effective first-line intervention to treat patients with moderate to severe acute respiratory distress syndrome (ARDS) receiving invasive mechanical ventilation, as it improves gas exchanges and reduces mortality. The use of PP in awake spontaneous breathing patients with ARDS secondary to COVID-19 was reported to improve oxygenation in few retrospective trials with small sample size. High-level evidence of awake PP for hypoxaemic patients with COVID-19 patients is still lacking.

METHODS AND ANALYSIS

The protocol of this meta-trial is a prospective collaborative individual participant data meta-analysis of randomised controlled open label superiority trials. This design is particularly adapted to a rapid scientific response in the pandemic setting. It will take place in multiple sites, among others in USA, Canada, Ireland, France and Spain. Patients will be followed up for 28 days. Patients will be randomised to receive whether awake PP and nasal high flow therapy or standard medical treatment and nasal high flow therapy. Primary outcome is defined as the occurrence rate of tracheal intubation or death up to day 28. An interim analysis plan has been set up on aggregated data from the participating research groups.

ETHICS AND DISSEMINATION

Ethics approvals were obtained in all participating countries. Results of the meta-trial will be submitted for publication in a peer-reviewed journal. Each randomised controlled trial was registered individually, as follows: NCT04325906, NCT04347941, NCT04358939, NCT04395144 and NCT04391140.

[Alternative CPAP methods for the treatment of secondary serious respiratory failure due to pneumonia by COVID-19]

Introducción

El uso de dispositivos que aportan presión positiva continua en la vía aérea ha demostrado mejoría en diversas patologías que producen insuficiencia respiratoria. En el episodio de pandemia por COVID-19, el uso de estos dispositivos se ha generalizado, pero, debido a la escasez de dispositivos convencionales de presión positiva continua en la vía aérea (CPAP), se han fabricado dispositivos alternativos. El objetivo de este estudio es describir el uso de estos, así como su eficacia.

Material y métodos

Se recogen datos de pacientes ingresados por neumonía por COVID-19 en el Hospital de Campaña de IFEMA, así como datos de pacientes con insuficiencia respiratoria y necesidad de soporte ventilatorio.

Resultados

Estudio realizado sobre un total de 23 pacientes, con fecha de ingreso de entre el 24 de marzo y el 28 de abril en IFEMA. Se empleó CPAP alternativa en cinco pacientes (21,7%), mientras que, en los 18 restantes (78,3%) se usó un soporte ventilatorio con mascarilla reservorio o Ventimask efecto Venturi. Se observó un aumento progresivo de la saturación en aquellos pacientes en los que se empleó CPAP alternativa (de 94% de promedio a 98 y 99% de promedio, tras 30 y 60 minutos con la máscara, respectivamente), aunque este cambio no resultó significativo (p = 0,058 y p = 0,122, respectivamente). De igual manera, no se observó un cambio significativo de frecuencia respiratoria al inicio y al final de la medición en pacientes que usaron CPAP alternativa (p = 0,423) pero sí entre los que no la usaron (p = 0,001). Se observó una mejoría estadísticamente significativa en la variable de saturación de oxígeno/fracción inspirado de oxígeno en los pacientes que usaron CPAP alternativa (p = 0,040).

Conclusión

El uso de estos dispositivos ha ayudado al trabajo ventilatorio de varios pacientes, mejorando sus parámetros de oxigenación. Para observar mejor la evolución de los pacientes sometidos a esta terapia y compararlos con pacientes con otro tipo de soporte ventilatorio, son necesarios más estudios en los que se aleatorice su uso.

Acute hypoxaemic respiratory failure in a low-income country: a prospective observational study of hospital prevalence and mortality

INTRODUCTION

Limited data exist on the epidemiology of acute hypoxaemic respiratory failure (AHRF) in low-income countries (LICs). We sought to determine the prevalence of AHRF in critically ill adult patients admitted to a Ugandan tertiary referral hospital; determine clinical and treatment characteristics as well as assess factors associated with mortality.

MATERIALS AND METHODS

We conducted a prospective observational study at the Mulago National Referral and Teaching Hospital in Uganda. Critically ill adults who were hospitalised at the emergency department and met the criteria for AHRF (acute shortness of breath for less than a week) were enrolled and followed up for 90 days. Multivariable analyses were conducted to determine the risk factors for death.

RESULTS

A total of 7300 patients was screened. Of these, 327 (4.5%) presented with AHRF. The majority (60 %) was male and the median age was 38 years (IQR 27-52). The mean plethysmographic oxygen saturation (SpO₂) was 77.6% (SD 12.7); mean SpO₂/FiO₂ ratio 194 (SD 32) and the mean Lung Injury Prediction Score (LIPS) 6.7 (SD 0.8). Pneumonia (80%) was the most common diagnosis. Only 6% of the patients received mechanical ventilatory support. In-hospital mortality was 77% with an average length of hospital stay of 9.2 days (SD 7). At 90 days after enrolment, the mortality increased to 85%. Factors associated with mortality were severity of hypoxaemia (risk ratio (RR) 1.29 (95% CI 1.15 to 1.54), p=0.01); a high LIPS (RR 1.79 (95% CI 1.79 1.14 to 2.83), p=0.01); thrombocytopenia (RR 1.23 (95% CI 1.11 to 1.38), p=0.01); anaemia (RR 1.15 (95% CI 1.01 to 1.31), p=0.03) ; HIV co-infection (RR 0.84 (95% CI 0.72 to 0.97), p=0.019) and male gender (RR 1.15 (95% CI 1.01 to 1.31) p=0.04).

CONCLUSIONS

The prevalence of AHRF among emergency department patients in a tertiary hospital in an LIC was low but was associated with very high mortality. Pneumonia was the most common cause of AHRF. Mortality was associated with higher severity of hypoxaemia, high LIPS, anaemia, HIV co-infection, thrombocytopenia and being male.

The index of oxygenation to respiratory rate as a prognostic factor for mortality in Sepsis

OBJECTIVES

An index combining respiratory rate and oxygenation (ROX) has been introduced, and the ROX index is defined as the ratio of oxygen saturation by pulse oximetry/fraction of inspired oxygen to respiratory rate. In sepsis, hypoxemia and tachypnea are commonly observed. We performed this study to investigate the association between the ROX index and 28-day mortality in patients with sepsis or septic shock.

METHODS

This retrospective study included 2862 patients. The patients were divided into three groups according to the ROX index: Group I (ROX index >20), Group II (ROX index >10 and ≤ 20), and Group III (ROX index ≤10).

RESULTS

The median ROX index was significantly lower in the nonsurvivors than in the survivors (12.8 and 18.2, respectively) (p < 0.001). The 28-day mortality rates in Groups I, II and III were 14.5%, 21.3% and 34.4%, respectively (p < 0.001). In the multivariable Cox regression analysis, Group III had an approximately 40% higher risk of death than Group I during the 28-day period (hazard ratio = 1.41, 95% confidence interval 1.13-1.76). The area under the curve of the ROX index was significantly higher than that of the quick Sequential Organ Failure Assessment score (p < 0.001).

CONCLUSIONS

The ROX index was lower in nonsurvivors than in survivors, and a ROX index less than or equal to 10 was an independent prognostic factor for 28-day mortality in patients with sepsis or septic shock. Therefore, the ROX index could be used as a prognostic marker in sepsis.

Continuously available ratio of SpO2/FiO2 serves as a noninvasive prognostic marker for intensive care patients with COVID-19

RATIONALE

Oxygen saturation to fraction of inspired oxygen ratio (SpO2/FiO2) has been described as potential predictor of poor outcome for COVID-19, without considering its time-varying behavior though.

METHODS

Prognostic value of SpO2/FiO2 was evaluated by jointly modeling the longitudinal responses of SpO2/FiO2 and time-to-event data retrieved from 280 severe and critically ill (intensive care) patients with COVID-19.

RESULTS

A sharply decrease of SpO2/FiO2 from the first to second measurement for non-survivors was observed, and a strong association between square root SpO2/FiO2 and mortality risk was demonstrated, with a unit decrease in the marker corresponding to 1.82-fold increase in mortality risk (95% CI: 1.56-2.13).

CONCLUSIONS

The current study suggested that SpO2/FiO2 could serve as a non-invasive prognostic marker to facilitate early adjustment for treatment, thus improving overall survival.

Respiratory Support in COVID-19 Patients, with a Focus on Resource-Limited Settings

The ongoing novel coronavirus disease (COVID-19) pandemic is threatening the global human population, including in countries with resource-limited health facilities. Severe bilateral pneumonia is the main feature of severe COVID-19, and adequate ventilatory support is crucial for patient survival. Although our knowledge of the disease is still rapidly increasing, this review summarizes current guidance on the best provision of ventilatory support, with a focus on resource-limited settings. Key messages include that supplemental oxygen is a first essential step for the treatment of severe COVID-19 patients with hypoxemia and should be a primary focus in resource-limited settings where capacity for invasive ventilation is limited. Oxygen delivery can be increased by using a non-rebreathing mask and prone positioning. The presence of only hypoxemia should in general not trigger intubation because hypoxemia is often remarkably well tolerated. Patients with fatigue and at risk for exhaustion, because of respiratory distress, will require invasive ventilation. In these patients, lung protective ventilation is essential. Severe pneumonia in COVID-19 differs in some important aspects from other causes of severe pneumonia or acute respiratory distress syndrome, and limiting the positive end-expiratory pressure level on the ventilator may be important. This ventilation strategy might reduce the currently very high case fatality rate of more than 50% in invasively ventilated COVID-19 patients.

Extracellular nucleic acid scavenging rescues rats from sulfur mustard analog-induced lung injury and mortality

Sulfur mustard (SM) is a highly toxic war chemical that causes significant morbidity and mortality and lacks any effective therapy. Rats exposed to aerosolized CEES (2-chloroethyl ethyl sulfide; 10% in ethanol), an analog of SM, developed acute respiratory distress syndrome (ARDS), which is characterized by increased inflammation, hypoxemia and impaired gas exchange. We observed elevated levels of extracellular nucleic acids (eNA) in the bronchoalveolar lavage fluid (BALF) of CEES-exposed animals. eNA can induce inflammation, coagulation and barrier dysfunction. Treatment with hexadimethrine bromide (HDMBr; 10 mg/kg), an eNA neutralizing agent, 2 h post-exposure, reduced lung injury, inhibited disruption of alveolar-capillary barrier, improved blood oxygenation (PaO₂/FiO₂ ratio), thus reversing ARDS symptoms. HDMBr treatment also reduced lung inflammation in the CEES-exposed animals by decreasing IL-6, IL-1A, CXCL-1 and CCL-2 mRNA levels in lung tissues and HMGB1 protein in BALF. Furthermore, HDMBr treatment also reduced levels of lung tissue factor and plasminogen activator inhibitor-1 indicating reduction in clot formation and increased fibrinolysis. Fibrin was reduced in BALF of the HDMBr-treated animals. This was further confirmed by histology that revealed diminished airway fibrin, epithelial sloughing and hyaline membrane in the lungs of HDMBr-treated animals. HDMBr completely rescued the CEES-associated mortality 12 h post-exposure when the survival rate in CEES-only group was just 50%. Experimental eNA treatment of cells caused increased inflammation that was reversed by HDMBr. These results demonstrate a role of eNA in the pathogenesis of CEES/SM-induced injury and that its neutralization can serve as a potential therapeutic approach in treating SM toxicity.

Association Between Peripheral Blood Oxygen Saturation (SpO2)/Fraction of Inspired Oxygen (FiO2) Ratio Time at Risk and Hospital Mortality in Mechanically Ventilated Patients

INTRODUCTION

Acute respiratory failure requiring mechanical ventilation is a leading cause of mortality in the intensive care unit. Although single peripheral blood oxygen saturation/fraction of inspired oxygen (SpO2/FiO2) ratios of hypoxemia have been evaluated to risk-stratify patients with acute respiratory distress syndrome, the utility of longitudinal SpO2/FiO2 ratios is unknown.

OBJECTIVE

To assess time-based SpO2/FiO2 ratios ≤ 150-SpO2/FiO2 time at risk (SF-TAR)-for predicting mortality in mechanically ventilated patients.

METHODS

Retrospective, observational cohort study of mechanically ventilated patients at 21 community and 2 academic hospitals. Association between the SF-TAR in the first 24 hours of ventilation and mortality was examined using multivariable logistic regression and compared with the worst recorded isolated partial pressure of arterial oxygen/fraction of inspired oxygen (P/F) ratio.

RESULTS

In 28,758 derivation cohort admissions, every 10% increase in SF-TAR was associated with a 24% increase in adjusted odds of hospital mortality (adjusted odds ratio = 1.24; 95% confidence interval [CI] = 1.23-1.26); a similar association was observed in validation cohorts. Discrimination for mortality modestly improved with SF-TAR (area under the receiver operating characteristic curve [AUROC] = 0.81; 95% CI = 0.81-0.82) vs the worst P/F ratio (AUROC = 0.78; 95% CI = 0.78-0.79) and worst SpO2/FiO2 ratio (AUROC = 0.79; 95% CI = 0.79-0.80). The SF-TAR in the first 6 hours offered comparable discrimination for hospital mortality (AUROC = 0.80; 95% CI = 0.79-0.80) to the 24-hour SF-TAR.

CONCLUSION

The SF-TAR can identify ventilated patients at increased risk of death, offering modest improvements compared with single SpO2/FiO2 and P/F ratios. This longitudinal, noninvasive, and broadly generalizable tool may have particular utility for early phenotyping and risk stratification using electronic health record data in ventilated patients.

PICU Admission Rates in Pediatric Cancer and Hematopoietic Stem Cell Transplant Patients Receiving High-flow Nasal Cannula Oxygen Therapy on the General Ward

The use of high-flow nasal cannula (HFNC) oxygen therapy is growing as an alternative to standard oxygen. However, its use in patients treated for malignancies, including hematopoietic stem cell transplantation (HSCT) patients, is controversial. In this retrospective cohort study, we assessed outcomes of pediatric cancer and HSCT patients (including nonmalignant indications) with acute hypoxemic respiratory failure treated with HFNC on the ward. Among 39 patients included in the study, 53 episodes of HFNC treatment were analyzed. Of these episodes, 18 (34%) failed and patients required subsequently pediatric intensive care unit (PICU) admission. A significant median higher C reactive protein (175 [range, 72 to 308] vs. 80 [13.5 to 187.8] mg/dL; P=0.006) and higher Bedside Pediatric Early Warning Score (PEWS) 1 to 4 hours after initiation of HFNC (10.1±0.8 vs. 7.1±0.4; P=0.001) was found in the failure group compared with the nonfailure group. Among the 18 patients admitted to PICU, 14 (78%) needed intubation. Five (28%) patients died during their PICU admission. In summary, one third of the pediatric cancer and HSCT patients receiving HFNC on the ward eventually required PICU admission of which 78% were intubated. C reactive protein and BedsidePEWS 1 to 4 hours after initiation of HFNC were significantly associated with the need for PICU admission. However, no firm conclusion can be drawn whether HFNC treatment should actually be initiated in the ward in this vulnerable patient population. Larger, prospective studies are needed to evaluate the most appropriate treatment and setting (PICU or general ward) for these patients.

Evaluation of pulse oximetry as a surrogate for PaO2 in awake dogs breathing room air and anesthetized dogs on mechanical ventilation

OBJECTIVE

To evaluate the ability of arterial hemoglobin oxygen saturation measurement via pulse oximetry (SpO2 ) to serve as a surrogate for PaO2 in dogs.

DESIGN

Two-part study: prospective observational and retrospective components.

SETTING

University teaching hospital.

ANIMALS

Ninety-two dogs breathing room air prospectively enrolled on a convenience basis. Retrospective evaluation of 1,033 paired SpO2 and PaO2 measurements from 62 dogs on mechanical ventilation.

INTERVENTIONS

Dogs with concurrent SpO2 and PaO2 measured on room air had a data sheet completed with blood gas analysis. SpO2 , PaO2 , and FiO2 values were collected from medical records of dogs on mechanical ventilation.

MEASUREMENTS AND MAIN RESULTS

Predicted PaO2 was calculated from SpO2 using the dog oxyhemoglobin dissociation curve. The correlation coefficient between measured and predicted PaO2 was 0.49 (P < 0.0001) in room air dogs and 0.74 (P < 0.0001) in ventilated dogs. In room air dogs, Bland-Altman analysis between measured minus predicted PaO2 versus the average showed a mean bias of -6.0 mm Hg (95% limit of agreement, -35 to 23 mm Hg). The correlation coefficient between PaO2 /FiO2 and SpO2 /FiO2 ratios was 0.76 (P < 0.0001). After combining data sets, receiver operating characteristic curve analysis showed the optimal cutoff value for detecting hypoxemia (PaO2  < 80 mm Hg) was an SpO2 of 95%, with sensitivity and specificity of 77.8% and 89.5%, respectively. Using this cutoff, 6.9% of SpO2 readings failed to detect hypoxemia, whereas 7.2% predicted hypoxemia that was not present.

CONCLUSIONS

The SpO2 was not clinically suitable as a surrogate for PaO2 , though it performed better in mechanically ventilated dogs. As sensitivity for the detection of hypoxemia was poor, pulse oximetry does not appear to be an acceptable screening test. The SpO2 /FiO2 ratio may have value for evaluation of anesthetized dogs on supplemental oxygen. Arterial blood gas analysis remains ideal for assessment of oxygenation.

Epoprostenol Delivered via High Flow Nasal Cannula for ICU Subjects with Severe Hypoxemia Comorbid with Pulmonary Hypertension or Right Heart Dysfunction

Inhaled epoprostenol (iEPO) has been utilized to improve oxygenation in mechanically ventilated subjects with severe hypoxemia, but the evidence for iEPO via high-flow nasal cannula (HFNC) is rare. Following approval by the institutional review board, this retrospective cohort study evaluated subjects who received iEPO via HFNC for more than 30 min to treat severe hypoxemia comorbid with pulmonary hypertension or right heart dysfunction between July 2015 and April 2018. A total of 11 subjects were enrolled in the study of whom 4 were male (36.4%), age 57.5 ± 22.1 years, and APACHE II score at ICU admission was 18.5 ± 5.7. Ten subjects had more than three chronic heart or lung comorbidities; seven of them used home oxygen. After inhaling epoprostenol, subjects' SpO₂/F_IO₂ ratio improved from 107.5 ± 26.3 to 125.5 ± 31.6 (p = 0.026) within 30-60 min. Five subjects (45.5%) had SpO₂/F_IO₂ improvement >20%, which was considered as a positive response. Heart rate, blood pressure, and respiratory rate were not significantly different. Seven subjects did not require intubation, and seven subjects were discharged home. This retrospective study demonstrated the feasibility of iEPO via HFNC in improving oxygenation. Careful titration of flow while evaluating subjects' response may help identify responders and avoid delaying other interventions. This study supports the need for a larger prospective randomized control trial to further evaluate the efficacy of iEPO via HFNC in improving outcomes.

Acute Respiratory Distress in the Operating Room and Prone Ventilation: A Case Report

There have been many advances in the management of acute respiratory distress syndrome, a condition which Bellani et al, in the LUNG SAFE trial (Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure), found represents up to 10.4% of intensive care unit admissions and 23.4% of patients requiring mechanical ventilation, with an unadjusted intensive care unit and hospital mortality of 35.3% and 40%, respectively. Studies have shown that prone positioning can improve oxygenation in patients who are mechanically ventilated for acute respiratory distress syndrome. This case report describes an example in which intraoperative prone positioning improved oxygenation in a patient after aspiration of gastric contents on induction of general anesthesia.

Clinical Profile and Predictors of Outcome of Pediatric Acute Respiratory Distress Syndrome in a PICU: A Prospective Observational Study

OBJECTIVES

To study the clinical profile, predictors of mortality, and outcomes of pediatric acute respiratory distress syndrome.

DESIGN

A prospective observational study.

SETTING

PICU, Advanced Pediatric Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

PATIENTS

All children (age > 1 mo to < 14 yr) admitted in PICU with a diagnosis of pediatric acute respiratory distress syndrome (as per Pediatric Acute Lung Injury Consensus Conference definition) from August 1, 2015, to November 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Out of 1,215 children admitted to PICU, 124 (11.4%) had pediatric acute respiratory distress syndrome. Fifty-six children (45.2%) died. Median age was 2.75 years (1.0-6.0 yr) and 66.9% were male. Most common primary etiologies were pneumonia, severe sepsis, and scrub typhus. Ninety-seven children (78.2%) were invasively ventilated. On multiple logistic regressions, Lung Injury Score (p = 0.004), pneumothorax (p = 0.012), acute kidney injury at enrollment (p = 0.033), FIO2-D1 (p = 0.018), and PaO2/FIO2 ratio-D7 (p = 0.020) were independent predictors of mortality. Positive fluid balance (a cut-off value > 102.5 mL/kg; p = 0.016) was associated with higher mortality at 48 hours. Noninvasive oxygenation variables like oxygenation saturation index and saturation-FIO2 ratio were comparable to previously used invasive variables (oxygenation index and PaO2/FIO2 ratio) in monitoring the course of pediatric acute respiratory distress syndrome.

CONCLUSIONS

Pediatric acute respiratory distress syndrome contributes to a significant burden in the PICU of a developing country and is associated with significantly higher mortality. Infection remains the most common etiology. Higher severity of illness scores at admission, development of pneumothorax, and a positive fluid balance at 48 hours predicted poor outcome.

Risk factors, characteristics, and outcomes of acute respiratory distress syndrome in dogs and cats: 54 cases

OBJECTIVE

To characterize the clinical features of the acute respiratory distress syndrome (ARDS), risk factors, and outcome in dogs and cats. The study also aimed to evaluate the current veterinary criteria for the diagnosis of ARDS by comparison of clinical diagnostic criteria with necropsy findings.

DESIGN

Retrospective study.

ANIMALS

Fifty-four client-owned animals, 46 dogs and 8 cats.

INTERVENTIONS

Medical records were reviewed for patients with the diagnosis of ARDS based on previously published clinical criteria or necropsy diagnosis. Signalment, clinical findings, and outcome were recorded.

MEASUREMENTS AND MAIN RESULTS

Animals were grouped according to a clinical or necropsy diagnosis: 43/54 (80%) were diagnosed with ARDS based on clinical criteria (group 1) and 11/54 (20%) were diagnosed with ARDS based on necropsy only (group 2). In group 1, 22/43 (51%) had a necropsy, which confirmed ARDS in 12/22 (54%). Direct (pulmonary) causes of ARDS were more common than indirect causes in dogs, while cats had a similar occurrence of direct and indirect causes. The most common risk factors identified in dogs were aspiration pneumonia (42%), systemic inflammatory response syndrome (SIRS) (29%), and shock (29%). All cats diagnosed clinically with ARDS had SIRS with or without sepsis. Of the animals with a clinical diagnosis of ARDS, 49% received mechanical ventilation and 58% received treatment (with or without mechanical ventilation) for 24 hours or longer. The overall case fatality rate was 84% in dogs and 100% in cats.

CONCLUSIONS AND CLINICAL RELEVANCE

As described in human literature, pneumonia was the most common risk factor in dogs with ARDS, whereas it was SIRS for the cat population. The high mortality rate and discrepancy between the clinical diagnosis and necropsy findings may highlight limitations in the clinical criteria for the diagnosis of ARDS and treatment in dogs and cats.

Small Airway Dysfunction Impairs Quality of Life Among Smokers With No Airflow Limitation

INTRODUCTION

Small airway dysfunction (SAD) caused by smoking contributes to the early onset of airflow limitation (AFL), although its impact on patients' perception of health is largely unknown. We aimed to evaluate the frequency of SAD in active smokers without AFL, and to compare health-related quality of life (HRQoL) of non-smokers, smokers without SAD, smokers with SAD, and smokers with AFL.

METHODS

A total of 53 active smokers without AFL, 20 smokers with AFL, and 20 non-smokers completed the SF-36 and EuroQoL questionnaires and performed impulse oscillometry and spirometry. Pulmonary parenchymal attenuation was determined in inspiration and expiration. SAD was determined to exist when resistance at 5Hz (R5), the difference between R5 and R20, and reactance area (AX) exceeded the upper limit of normal.

RESULTS

In total, 35.8% of smokers without AFL had SAD. No differences were detected in spirometric parameters or pulmonary attenuation between smokers with or without AFL and non-smokers. However, smokers with SAD had worse scores on HRQoL questionnaires than smokers without SAD or non-smokers, and scores compared to smokers with AFL were intermediate. R5 and X5 were identified as independent determinants of HRQoL in smokers without AFL.

CONCLUSIONS

SAD is common in smokers without AFL, affecting one third of this population, and independently affecting their perception of health.

Vascular endothelial cadherin shedding is more severe in sepsis patients with severe acute kidney injury

BACKGROUND

Vascular endothelial cadherin (VE-cadherin) is a membrane protein that is the major component of adherens junctions between endothelial cells. It is crucial for regulating vascular integrity, endothelial permeability, and angiogenesis. During inflammatory processes, VE-cadherin is shed into circulation (sVE-cadherin). Plasma sVE-cadherin is elevated in sepsis, malignancy, autoimmune diseases, and coronary atherosclerosis. However, the relationship between specific organ failures, especially severe acute kidney injury (AKI) defined by requirement for renal replacement therapy (AKI-RRT), and plasma sVE-cadherin levels in severe sepsis has not been well studied.

METHODS

The present study is a prospective study of critically ill adults with sepsis and acute respiratory failure (age ≥ 18 years) enrolled in the Validating Acute Lung Injury markers for Diagnosis (VALID) study. Plasma sVE-cadherin was measured at study enrollment. Primary analysis focused on the association between sVE-cadherin levels and the development of AKI, AKI-RRT, other organ dysfunction as defined by Brussels organ failure scores, pulmonary versus non-pulmonary sepsis, acute respiratory distress syndrome (ARDS), and in-hospital mortality.

RESULTS

Of 228 severe sepsis patients included, 80 (35%) developed AKI-RRT. Plasma sVE-cadherin levels at enrollment were significantly higher in patients with AKI-RRT compared with patients without AKI-RRT (p = 0.003). Plasma sVE-cadherin levels by quartile were significantly higher in severe sepsis patients with acute kidney injury stage 3 (p = 0.044) as defined by Kidney Disease Improving Global Outcomes (KDIGO) criteria. Patients with greater than 2 organ failures had higher plasma sVE-cadherin levels than patients with 2 or fewer organ failures (p < 0.001). In a multivariable analysis, plasma sVE-cadherin was independently associated with AKI-RRT (odds ratio 6.44 per log increase in plasma sVE-cadherin, 95% CI 1.126-36.847, p = 0.036). Plasma sVE-cadherin levels were significantly higher in patients with non-pulmonary sepsis compared to pulmonary sepsis (p < 0.001).

CONCLUSION

Shedding of sVE-cadherin is associated with severe acute kidney injury and with more severe organ dysfunction in patients with sepsis, suggesting that breakdown of endothelial adherens junctions may contribute to the pathogenesis of organ dysfunction in sepsis. Further studies of sVE-cadherin as a biomarker of disease severity in clinical sepsis are needed to better elucidate the role of VE-cadherin shedding in sepsis-induced severe organ dysfunction.

The Value of Oxygenation Saturation Index in Predicting the Outcomes of Patients with Acute Respiratory Distress Syndrome

This study aims to investigate the association between oxygenation saturation index (OSI) and the outcome of acute respiratory distress syndrome (ARDS) patients, and assess the predictive performance of OSI for ARDS patients’ mortality. This study was conducted at one regional hospital with 66 adult intensive care unit (ICU) beds. All patients with ARDS were identified between November 1 2016 and May 31 2018, and their clinical information was retrospectively collected. The lowest PaO₂/FiO₂ ratio and SpO₂/FiO₂ ratio and highest mean airway pressure (MAP) were recorded on the first day of ARDS; and oxygen index (OI) and OSI were calculated as (FiO₂ × MAP × 100)/PaO₂, and (FiO₂ × MAP × 100) /SpO₂ accordingly. During the study period, a total of 101 patients with ARDS were enrolled, and their mean age was 69.2 years. The overall in-ICU and in-hospital mortality rate was 57.4% and 61.4%, respectively. The patients with in-ICU mortality had higher APACHE II score than the survivors (31.6 ± 9.8 vs. 23.0 ± 9.1, p < 0.001). In addition, mortalities had lower SpO₂, and SpO₂/FiO₂ ratios than the survivors (both p < 0.05). In contrast, survivors had lower OI, and OSI than the mortalities (both p = 0.008). Both OSI (area under curve (AUC) = 0.656, p = 0.008) and OI (AUC = 0.654, p = 0.008) had good predictive performance of mortality among ARDS patients using receiver-operating characteristics (ROC) curves analysis. In addition, the AUC of SpO₂/FiO₂ (AUC = 0.616, p = 0.046) had better performance for mortality prediction than PaO₂/FiO₂ (AUC = 0.603, p = 0.08). The patients with OSI greater than 12 had a higher risk of mortality than OSI < 12 (adjusted OR, 5.22, 95% CI, 1.31–20.76, p = 0.019). In contrast, OI, PaO₂/FiO₂, and SpO₂/FiO₂ were not found to be significantly associated with increased mortality. OSI is significantly associated with the increased mortality of ARDS patients and can also be a good outcome predictor.

Evaluation of the SpO2/FiO2 ratio as a predictor of intensive care unit transfers in respiratory ward patients for whom the rapid response system has been activated

Efforts to detect patient deterioration early have led to the development of early warning score (EWS) models. However, these models are disease-nonspecific and have shown variable accuracy in predicting unexpected critical events. Here, we propose a simpler and more accurate method for predicting risk in respiratory ward patients. This retrospective study analyzed adult patients who were admitted to the respiratory ward and detected using the rapid response system (RRS). Study outcomes included transfer to the intensive care unit (ICU) within 24 hours after RRS activation and in-hospital mortality. Prediction power of existing EWS models including Modified EWS (MEWS), National EWS (NEWS), and VitalPAC EWS (ViEWS) and SpO₂/FiO₂ (SF) ratio were compared to each other using the area under the receiver operating characteristic curve (AUROC). Overall, 456 patients were included; median age was 75 years (interquartile range: 65–80) and 344 (75.4%) were male. Seventy-three (16.0%) and 79 (17.3%) patients were transferred to the ICU and died. The SF ratio displayed better or comparable predictive accuracy for unexpected ICU transfer (AUROC: 0.744) compared to MEWS (0.744 vs. 0.653, P = 0.03), NEWS (0.744 vs. 0.667, P = 0.04), and ViEWS (0.744 vs. 0.675, P = 0.06). For in-hospital mortality, although there was no statistical difference, the AUROC of the SF ratio (0.660) was higher than that of each of the preexisting EWS models. In comparison with the preexisting EWS models, the SF ratio showed better or comparable predictive accuracy for unexpected ICU transfers in the respiratory wards.

Fibroblast Growth Factor 23 Associates with Death in Critically Ill Patients

BACKGROUND AND OBJECTIVES

Dysregulated mineral metabolism is a common and potentially maladaptive feature of critical illness, especially in patients with AKI, but its association with death has not been comprehensively investigated. We sought to determine whether elevated plasma levels of the osteocyte-derived, vitamin D-regulating hormone, fibroblast growth factor 23 (FGF23), are prospectively associated with death in critically ill patients with AKI requiring RRT, and in a general cohort of critically ill patients with and without AKI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We measured plasma FGF23 and other mineral metabolite levels in two cohorts of critically ill patients (n=1527). We included 817 patients with AKI requiring RRT who enrolled in the ARF Trial Network (ATN) study, and 710 patients with and without AKI who enrolled in the Validating Acute Lung Injury biomarkers for Diagnosis (VALID) study. We hypothesized that higher FGF23 levels at enrollment are independently associated with higher 60-day mortality.

RESULTS

In the ATN study, patients in the highest compared with lowest quartiles of C-terminal (cFGF23) and intact FGF23 (iFGF23) had 3.84 (95% confidence interval, 2.31 to 6.41) and 2.08 (95% confidence interval, 1.03 to 4.21) fold higher odds of death, respectively, after adjustment for demographics, comorbidities, and severity of illness. In contrast, plasma/serum levels of parathyroid hormone, vitamin D metabolites, calcium, and phosphate were not associated with 60-day mortality. In the VALID study, patients in the highest compared with lowest quartiles of cFGF23 and iFGF23 had 3.52 (95% confidence interval, 1.96 to 6.33) and 1.93 (95% confidence interval, 1.12 to 3.33) fold higher adjusted odds of death.

CONCLUSIONS

Higher FGF23 levels are independently associated with greater mortality in critically ill patients.

GBT1118, a compound that increases the oxygen affinity of hemoglobin, improves survival in murine hypoxic acute lung injury

Acute respiratory distress syndrome (ARDS) is characterized by lung inflammation and pulmonary edema, leading to arterial hypoxemia and death if the hypoxemia is severe. Strategies to correct hypoxemia have the potential to improve clinical outcomes in ARDS. The goal of this study was to evaluate the potential of hemoglobin modification as a novel therapy for ARDS-induced hypoxemia. The therapeutic effect of two different doses of GBT1118, a compound that increases the oxygen affinity of hemoglobin, was evaluated in a murine model of acute lung injury induced by intratracheal LPS instillation 24 h before exposure to 5% or 10% hypoxia ( n = 8-15 per group). As expected, administration of GBT1118 to mice significantly increased the oxygen affinity of hemoglobin. Compared with mice receiving vehicle control, mice treated with GBT1118 had significantly lower mortality after LPS + 5% hypoxia (47% with vehicle vs. 22% with low-dose GBT1118, 13% with high-dose GBT1118, P = 0.032 by log rank) and had reduced severity of illness. Mice treated with GBT1118 showed a sustained significant increase in SpO₂ over 4 h of hypoxia exposure. Treatment with GBT1118 did not alter alveolar-capillary permeability, bronchoalveolar lavage (BAL) inflammatory cell counts, or BAL concentrations of IL-1β, TNF-α, or macrophage inflammatory protein-1α. High-dose GBT1118 did not affect histological lung injury but did decrease tissue hypoxia as measured intensity of pimonidazole (Hypoxyprobe) staining in liver ( P = 0.043) and kidney ( P = 0.043). We concluded that increasing the oxygen affinity of hemoglobin using GBT1118 may be a novel therapy for treating hypoxemia associated with acute lung injury. NEW & NOTEWORTHY In this study, we show that GBT1118, a compound that increases hemoglobin affinity for oxygen, improves survival and oxygen saturation in a two-hit lung injury model of intratracheal LPS without causing tissue hypoxia. Modulation of hemoglobin oxygen affinity represents a novel therapeutic approach to treatment of acute lung injury and acute respiratory distress syndrome, conditions characterized by hypoxemia.

Oxygenation Saturation Index Predicts Clinical Outcomes in ARDS

BACKGROUND

Traditional measures of ARDS severity such as Pao₂/Fio₂ may not reliably predict clinical outcomes. The oxygenation index (OI [Fio₂ × mean airway pressure × 100)/Pao₂]) may more accurately reflect ARDS severity but requires arterial blood gas measurement. We hypothesized that the oxygenation saturation index (OSI [Fio₂ × mean airway pressure × 100)/oxygen saturation by pulse oximetry (Spo₂)]) is a reliable noninvasive surrogate for the OI that is associated with hospital mortality and ventilator-free days (VFDs) in patients with ARDS.

METHODS

Critically ill patients enrolled in a prospective cohort study were eligible if they developed ARDS (Berlin criteria) during the first 4 ICU days and had mean airway pressure, Spo₂/Fio₂, and Pao₂/Fio₂ values recorded on the first day of ARDS (N = 329). The highest mean airway pressure and lowest Spo₂/Fio₂ and Pao₂/Fio₂ values were used to calculate OI and OSI. The association between OI or OSI and hospital mortality or VFD was analyzed by using logistic regression and linear regression, respectively. The area under the receiver-operating characteristic curve (AUC) for mortality was compared among OI, OSI, Spo₂/Fio₂, Pao₂/Fio₂, and Acute Physiology and Chronic Health Evaluation II scores.

RESULTS

OI and OSI were strongly correlated (rho = 0.862; P < .001). OSI was independently associated with hospital mortality (OR per 5-point increase in OSI, 1.228 [95% CI, 1.056-1.429]; P = .008). OI and OSI were each associated with a reduction in VFD (OI, P = .023; OSI, P = .005). The AUC for mortality prediction was greatest for Acute Physiology and Chronic Health Evaluation II scores (AUC, 0.695; P < .005) and OSI (AUC, 0.602; P = .007). The AUC for OSI was substantially better in patients aged < 40 years (AUC, 0.779; P < .001).

CONCLUSIONS

In patients with ARDS, the OSI was correlated with the OI. The OSI on the day of ARDS diagnosis was significantly associated with increased mortality and fewer VFDs. The findings suggest that OSI is a reliable surrogate for OI that can noninvasively provide prognostic information and assessment of ARDS severity.

Mechanical Ventilation in Patients with the Acute Respiratory Distress Syndrome and Treated with Extracorporeal Membrane Oxygenation: Impact on Hospital and 30 Day Postdischarge Survival

Mechanical ventilation support for acute respiratory distress syndrome (ARDS) patients involves the use of low tidal volumes and positive end-expiratory pressure. Nevertheless, the optimal ventilator strategy for ARDS patients undergoing extracorporeal membrane oxygenation (ECMO) therapy remains unknown. A retrospective analysis of a consecutive series of adult ARDS patients treated with V-V ECMO from October 2012 to May 2015 was performed. Mechanical ventilation data, as well as demographic and clinical data, were collected. We assessed the association between ventilator data and outcomes of interest. The primary outcome was hospital survival. Secondary outcome was 30 day survival posthospital discharge. Sixty-four ARDS patients were treated with ECMO. Univariate analysis showed that plateau pressure was independently associated with hospital survival. Tidal volume, positive end-expiratory pressure (PEEP), and plateau were independently associated with 30 day survival. Multivariate analysis, after controlling for covariates, revealed that a 1 unit increase in plateau pressure was associated with a 21% decrease in the odds of hospital survival (95% confidence interval [CI] = 6.39-33.42%, p = 0.007). In regards to 30 day survival postdischarge, a 1 unit increase in plateau pressure was associated with a 14.4% decrease in the odds of achieving the aforementioned outcome (95% CI = 1.75-25.4%, p = 0.027). Also, a 1 unit increase in PEEP was associated with a 36.2% decrease in the odds of 30 day survival (95% CI = 10.8-54.4%, p = 0.009). Among ARDS patients undergoing ECMO therapy, only plateau pressure is associated with hospital survival. Plateau pressure and PEEP are both associated with 30 day survival posthospital discharge.

Risk stratification using SpO2/FiO2 and PEEP at initial ARDS diagnosis and after 24 h in patients with moderate or severe ARDS

BACKGROUND

We assessed the potential of risk stratification of ARDS patients using SpO₂/FiO₂ and positive end-expiratory pressure (PEEP) at ARDS onset and after 24 h.

METHODS

We used data from a prospective observational study in patients admitted to a mixed medical-surgical intensive care unit of a university hospital in the Netherlands. Risk stratification was by cutoffs for SpO₂/FiO₂ and PEEP. The primary outcome was in-hospital mortality. Patients with moderate or severe ARDS with a length of stay of > 24 h were included in this study. Patients were assigned to four predefined risk groups: group I (SpO₂/FiO₂ ≥ 190 and PEEP < 10 cm H₂O), group II (SpO₂/FiO₂ ≥ 190 and PEEP ≥ 10 cm), group III (SpO₂/FiO₂ < 190 and PEEP < 10 cm H₂O) and group IV (SpO₂/FiO₂ < 190 and PEEP ≥ 10 cm H₂O).

RESULTS

The analysis included 456 patients. SpO₂/FiO₂ and PaO₂/FiO₂ had a strong relationship (P < 0.001, R ₂ = 0.676) that could be described in a linear regression equation (SpO₂/FiO₂ = 42.6 + 1.0 * PaO₂/FiO₂). Risk stratification at initial ARDS diagnosis resulted in groups that had no differences in in-hospital mortality. Risk stratification at 24 h resulted in groups with increasing mortality rates. The association between group assignment at 24 h and outcome was confounded by several factors, including APACHE IV scores, arterial pH and plasma lactate levels, and vasopressor therapy.

CONCLUSIONS

In this cohort of patients with moderate or severe ARDS, SpO₂/FiO₂ and PaO₂/FiO₂ have a strong linear relationship. In contrast to risk stratification at initial ARDS diagnosis, risk stratification using SpO₂/FiO₂ and PEEP after 24 h resulted in groups with worsening outcomes. Risk stratification using SpO₂/FiO₂ and PEEP could be practical, especially in resource-limited settings.

Predictive factors for the outcome of high flow nasal cannula therapy in a pediatric intensive care unit: Is the SpO2/FiO2 ratio useful?

OBJECTIVES

To determine the predictive factors for the outcome of high-flow nasal cannula (HFNC) therapy in a pediatric intensive care unit (PICU).

MATERIALS AND METHODS

We prospectively included all patients with acute respiratory distress/failure aged 1month to 18years who were admitted to the PICU between January 2015 and May 2016 and treated with HFNC as a primary support and for postextubation according to our pre-established protocol. HFNC failure was defined as the need for escalation to non-invasive ventilation (NIV) or invasive mechanical ventilation (MV). HFNC responders and nonresponders were compared based on clinical data obtained just before HFNC and at 30, 60, and 120min, 12, 24, and 48h, and at the end of therapy.

RESULTS

A total of 204 patients (median age: 16.5months) participated in the study. Twenty-six (12.7%) patients required escalation (4 to NIV and 22 to MV). Age >120months, higher PRISM-III and respiratory scores, and a lower SpO₂/FiO₂ (S/F) ratio at admission were predictors of HFNC failure. Achievement of the S/F>200 goal at 60min significantly predicted successful HFNC.

CONCLUSION

Monitoring the S/F ratio might be useful and practical to avoid delaying escalation to another ventilation support. Failure to achieve S/F>200 at 60min should be a warning for the escalation of respiratory support.

Retrospective evaluation of the prevalence, risk factors, management, outcome, and necropsy findings of acute lung injury and acute respiratory distress syndrome in dogs and cats: 29 cases (2011-2013)

OBJECTIVE

To determine the prevalence and risk factors for veterinary acute lung injury (VetALI) and veterinary acute respiratory distress syndrome (VetARDS), assess mechanical ventilation settings and patient outcomes, and to evaluate the relationship of clinical diagnoses with necropsy findings.

DESIGN

Retrospective study.

SETTING

University teaching hospital.

ANIMALS

Twenty-four dogs and 5 cats with a clinical diagnosis of VetALI or VetARDS. Control population includes 24 dogs and 5 cats with a clinical diagnosis of respiratory disease other than VetALI or VetARDS.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

VetALI and VetARDS were diagnosed in 3.2% of dogs and 1.3% of cats presenting to the ICU. Systemic inflammatory response syndrome was the most common inciting condition (16/24 dogs, 2/5 cats), followed by vomiting and subsequent aspiration of gastric contents (9/24 dogs), sepsis (5/24 dogs, 3/5 cats), multiple transfusions (4/24 dogs), trauma (3/24 dogs), and adverse drug reactions (1/24 dogs, 1/5 cats).  None of these conditions were found to be significantly associated with a risk of development of VetALI or VetARDS when compared to controls. Twelve dogs (50%) and 4 cats (80%) underwent mechanical ventilation for a median duration of 18 hours in dogs (range: 6-174 h) and 15.5 hours in cats (range: 6-91 h). Overall, 3/29 patients survived to discharge including 2/24 dogs and 1/5 cats. Necropsy results were available for 8/22 dogs and 3/4 cats. A total of 6/8 dogs (75%) dogs and 3/3 (100%) cats met the histopathologic criteria for diagnosis of VetALI or VetARDS.

CONCLUSIONS

VetALI and VetARDS can cause life-threatening respiratory distress in dogs and cats necessitating mechanical ventilation in 50% of dogs and 80% of cats in this study. These diseases are associated with a poor clinical outcome and a high rate of humane euthanasia.

Scoring model to predict outcome in critically ill cirrhotic patients with acute respiratory failure: comparison with MELD scoring models and CLIF-SOFA score

BACKGROUND

Critically ill cirrhotic patients have a high mortality, particularly with concomitant respiratory failure on admission. There are no specific models in use for mortality risk assessment in critically ill cirrhotic patients with acute respiratory failure (CICRF). The aim is to develop a risk prediction model specific to CICRF in order to quantify the severity of illness.

METHODS

We analyzed 949 CICRF patients extracted from the MIMIC-III database. The novel model (ARF-CLIF-SOFA) was developed from the CLIF-SOFA score. Cox regression analysis and AUROC were implemented to test the predictive accuracy, compared with existing scores including the CLIF-SOFA score and MELD-related scores.

RESULTS

ARF-CLIF-SOFA contains PaO₂/FiO₂ ratio, lactate, MAP, vasopressor therapy, bilirubin and creatinine (1 point each; score range: 0-6). Based on our patient cohort, the ARF-CLIF-SOFA score had good predictive accuracy for predicting the 30-, 90-day and 1-year mortality (AUROC = 0.767 at 30-day, 0.768 at 90-day, 0.765 at 1-year, respectively). Additionally, the performance of the ARF-CLIF-SOFA is superior to existing scores (all P < 0.001).

CONCLUSION

The ARF-CLIF-SOFA score can be considered a CICRF specific score with a better predictive accuracy compared to the existing scores.

External Validity of Electronic Sniffers for Automated Recognition of Acute Respiratory Distress Syndrome

INTRODUCTION

Automated electronic sniffers may be useful for early detection of acute respiratory distress syndrome (ARDS) for institution of treatment or clinical trial screening.

METHODS

In a prospective cohort of 2929 critically ill patients, we retrospectively applied published sniffer algorithms for automated detection of acute lung injury to assess their utility in diagnosis of ARDS in the first 4 ICU days. Radiographic full-text reports were searched for "edema" OR ("bilateral" AND "infiltrate") and a more detailed algorithm for descriptions consistent with ARDS. Patients were flagged as possible ARDS if a radiograph met search criteria and had a PaO₂/FiO₂ or SpO₂/FiO₂ of 300 or 315, respectively. Test characteristics of the electronic sniffers and clinical suspicion of ARDS were compared to a gold standard of 2-physician adjudicated ARDS.

RESULTS

Thirty percent of 2841 patients included in the analysis had gold standard diagnosis of ARDS. The simpler algorithm had sensitivity for ARDS of 78.9%, specificity of 52%, positive predictive value (PPV) of 41%, and negative predictive value (NPV) of 85.3% over the 4-day study period. The more detailed algorithm had sensitivity of 88.2%, specificity of 55.4%, PPV of 45.6%, and NPV of 91.7%. Both algorithms were more sensitive but less specific than clinician suspicion, which had sensitivity of 40.7%, specificity of 94.8%, PPV of 78.2%, and NPV of 77.7%.

CONCLUSIONS

Published electronic sniffer algorithms for ARDS may be useful automated screening tools for ARDS and improve on clinical recognition, but they are limited to screening rather than diagnosis because their specificity is poor.

Effect of ARDS Severity and Etiology on Short-Term Outcomes

BACKGROUND

We evaluated the outcome of subjects with ARDS in relation to etiology and severity in a retrospective cohort study of the ARDS Network randomized controlled trials. The primary outcome was 28-d mortality. The secondary outcomes were 60-d mortality and ventilator- and ICU-free days. For severity of ARDS, subjects were stratified according to P_aO2/F_IO2. The etiology of ARDS was classified into sepsis, pneumonia, aspiration, trauma, and others.

RESULTS

A total of 2,914 subjects were included in these trials. Outcomes were modeled with multivariable regressions adjusted for baseline covariates, age, sex, race, Acute Physiology and Chronic Health Evaluation III (APACHE III), vasopressor use, modified lung injury score, diabetes mellitus, cancer status, body mass index, pre-ICU location, ICU location, and study. There was no statistically significant difference in 28-d mortality in relation to ARDS severity. Subjects with trauma, compared with other etiologies of ARDS, had significantly lower mortality at 28 d (odds ratio [OR] = 0.47, 95% CI 0.26-0.83, P = .01). Sixty-day mortality was significantly lower for trauma subjects and those with severe ARDS group (OR = 0.5, 95% CI 0.3-0.85, P = .01 and OR = 0.71, 95% CI 0.52-0.98, P = .034, respectively). There were statistically significantly more ICU-free days and ventilator-free days for the aspiration group (OR = 1.09, 95% CI 1.02-1.17, P = .01 and OR = 1.09, 95% CI 1.02-1.16, P = .01, respectively). There was no statistically significant difference in ICU-free days or ventilator-free days in relation to severity of ARDS.

CONCLUSIONS

Severity of ARDS based on P_aO2/F_IO2 did not impact 28-d mortality, ventilator-free days, or ICU-free days. Among the etiologies of ARDS, trauma subjects had the lowest 28- and 60-d mortality, whereas subjects with aspiration had more ICU-free days and ventilator-free days.

Circulating microparticle levels are reduced in patients with ARDS

BACKGROUND

It is unclear how to identify which patients at risk for acute respiratory distress syndrome (ARDS) will develop this condition during critical illness. Elevated microparticle (MP) concentrations in the airspace during ARDS are associated with activation of coagulation and in vitro studies have demonstrated that MPs contribute to acute lung injury, but the significance of MPs in the circulation during ARDS has not been well studied. The goal of the present study was to test the hypothesis that elevated levels of circulating MPs could prospectively identify critically ill patients who will develop ARDS and that elevated circulating MPs are associated with poor clinical outcomes.

METHODS

A total of 280 patients with platelet-poor plasma samples from the prospective Validating Acute Lung Injury biomarkers for Diagnosis (VALID) cohort study were selected for this analysis. Demographics and clinical data were obtained by chart review. MP concentrations in plasma were measured at study enrollment on intensive care unit (ICU) day 2 and on ICU day 4 by MP capture assay. Activation of coagulation was measured by plasma recalcification (clot) times.

RESULTS

ARDS developed in 90 of 280 patients (32%) in the study. Elevated plasma MP concentrations were associated with reduced risk of developing ARDS (odds ratio (OR) 0.70 per 10 μM increase in MP concentration, 95% CI 0.50-0.98, p = 0.042), but had no significant effect on hospital mortality. MP concentration was greatest in patients with sepsis, pneumonia, or aspiration as compared with those with trauma or receiving multiple blood transfusions. MP levels did not significantly change over time. The inverse association of MP levels with ARDS development was most striking in patients with sepsis. After controlling for age, presence of sepsis, and severity of illness, higher MP concentrations were independently associated with a reduced risk of developing ARDS (OR 0.69, 95% CI 0.49-0.98, p = 0.038). MP concentration was associated with reduced plasma recalcification time.

CONCLUSIONS

Elevated levels of circulating MPs are independently associated with a reduced risk of ARDS in critically ill patients. Whether this is due to MP effects on systemic coagulation warrants further investigation.

A risk scoring model based on vital signs and laboratory data predicting transfer to the intensive care unit of patients admitted to gastroenterology wards

PURPOSE

To compare the ability of a score based on vital signs and laboratory data with that of the modified early warning score (MEWS) to predict ICU transfer of patients with gastrointestinal disorders.

MATERIALS AND METHODS

Consecutive events triggering medical emergency team activation in adult patients admitted to the gastroenterology wards of the Asan Medical Center were reviewed. Binary logistic regression was used to identify factors predicting transfer to the ICU. Gastrointestinal early warning score (EWS-GI) was calculated as the sum of simplified regression weights (SRW).

RESULTS

Of the 1219 included patients, 468 (38%) were transferred to the ICU. Multivariate analysis identified heart rate≥105bpm (SRW 1), respiratory rate≥26bpm (SRW 2), ACDU (Alert, Confused, Drowsy, Unresponsive) score≥1 (SRW 2), SpO₂/FiO₂ ratio<240 (SRW 2), creatinine ≥2.0mg/dL (SRW 2), total bilirubin ≥9.0mg/dL (SRW 2), prothrombin time/international normalized ratio (INR) ≥1.5 (SRW 2), and lactate ≥3.0mmol/L (SRW 2) for inclusion in EWS-GI. The area under the receiver operating characteristic curve of the EWS-GI was larger than that of MEWS (0.76 vs. 0.64; P<0.001).

CONCLUSIONS

EWS-GI may predict ICU transfer among patients admitted to gastroenterology wards. The EWS-GI should be prospectively validated.