Evaluation of HACOR scale as a predictor of non-invasive ventilation failure in acute cardiogenic pulmonary oedema patients: A prospective observational study

BACKGROUND AND IMPORTANCE

Acute cardiogenic pulmonary oedema (ACPO) is a common indication for non-invasive ventilation (NIV) in the emergency department (ED). HACOR score of >5 is used to predict NIV failure. The predictive ability of HACOR may be affected by altered physiological parameters in ACPO patients due to medications or comorbidities.

OBJECTIVES

To validate the HACOR scale in predicting NIV failure among acute cardiogenic pulmonary oedema (ACPO) patients.

DESIGN, SETTINGS AND PARTICIPANTS

This is a prospective, observational study of consecutive ACPO patients requiring NIV admitted to the ED.

OUTCOME MEASURE AND ANALYSIS

Primary outcome was the ability of the HACOR score to predict NIV failure. Clinical, physiological, and HACOR score at baseline and at 1 h, 12 h and 24 h were analysed. Other potential predictors were assessed as secondary outcomes.

MAIN RESULTS

A total of 221 patients were included in the analysis. Fifty-four (24.4%) had NIV failure. Optimal HACOR score was >5 at 1 h after NIV initiation in predicting NIV failure (AUC 0.73, sensitivity 53.7%, specificity 83.2%). As part of the HACOR score, respiratory rate and heart rate were not found to be significant predictors. Other significant predictors of NIV failure in ACPO patients were acute coronary syndrome, acute kidney injury, presence of congestive heart failure as a comorbid, and the ROX index.

CONCLUSIONS

The HACOR scale measured at 1 h after NIV initiation predicts NIV failure among ACPO patients with acceptable accuracy. The cut-off level > 5 could be a useful clinical decision support tool in ACPO patient. However, clinicians should consider other factors such as the acute coronary and acute kidney diagnosis at presentation, presence of underlying congestive heart failure and the ROX index when clinically deciding on timely invasive mechanical ventilation.

A pragmatic calibration of the ROX index to predict outcome of nasal high-flow therapy in India

PURPOSE

Identifying thresholds at which the ROX index would satisfactorily predict HFNC failure across heterogenous resourced contexts is necessary for clinical use.

METHODS

Patients ≥18 years admitted to 30 diverse ICUs across 10 states in India who required HFNC for respiratory support were retrospectively included in this study. Patient data and hourly ROX indices were then analyzed and contextualized to clinical outcomes as well as with ROX index thresholds in other regions of the world.

MEASUREMENTS AND MAIN RESULTS

Among the 614 patients included, 276 (44.9%) required respiratory escalation. Pneumonia was the most common diagnosis on admission. Receiver operating characteristic curve analysis revealed that a baseline ROX score of 7.86 was similar to 4.88 in other populations which was confirmed by Kaplan-Mier curves (hazard ratio,3.58 (2.72-4.69, p < 0.001)). ROX scores at 11.84 or 5.89 had roles in screening and confirming HFNC failure. The index performed poorly in a subset of patients who died without respiratory escalation. The ROX index was most predictive in the initial hours of ICU admission and a longer duration of HFNC was associated with more severe outcomes.

CONCLUSIONS

When optimally calibrated this index can using a method that can reliably predict the risk of HFNC failure among ICU patients from diverse settings.

Facet-dependent adsorption of aromatic organoarsenicals on hematite: The mechanism and environmental impact

Aromatic organoarsenic feed additives have been extensively used in poultry and livestock farming; however, a risk of releasing toxic inorganic arsenic exists when they are exposed to the environment. An in-depth understanding of the adsorption -migration behavior of aromatic organoarsenicals on environmental media is limited. In this study, p-arsanilic acid (p-ASA) and roxarsone (ROX) were considered as examples to systematically study their adsorption behaviors on the surface of hematite, a representative iron oxide in soil. By comparing the adsorption abilities and adsorption kinetics of hematite exposed with different facets (hexagonal nanoplates, HNPs, mainly exposed with {001} facets and hexagonal nanocubes, HNCs, exposed with {012} facets), combined with in situ shell-isolated nanoparticle enhanced Raman spectroscopy characterization and density functional theory simulation, the facet-dependent adsorption performance was observed and the mechanism revealed. The results showed that p-ASA formed a bidentate binuclear complex on HNCs and HNPs, whereas ROX formed monodentate mononuclear and bidentate binuclear configurations on the {001} and {012} facets, respectively. These differences not only lead to facet-dependent adsorption capacities but also affect their stability, as verified by sequential extraction experiments, affecting the environmental behavior and fate of aromatic organoarsenicals. This study not only provides insights into the environmental behavior of aromatic organoarsenicals but also offers theoretical support for the development of functional adsorbents and remediation strategies.

Comparison of Prognostic Scores for Patients with COVID-19 Presenting with Dyspnea in the Emergency Department

BACKGROUND

Easy-to-use bedside risk assessment is crucial for patients with COVID-19 in the overcrowded emergency department (ED).

OBJECTIVE

The aim of this study was to explore the prognostic ability of ratio of percutaneous oxygen saturation (SpO2) to fraction of inspired oxygen (FiO2) (S/F); ratio of SpO2/FiO2 to respiratory rate (ROX); National Early Warning Score (NEWS); quick Sequential Organ Failure Assessment (qSOFA); and confusion, respiratory rate, blood pressure, and age ≥ 65 years (CRB-65) in patients with COVID-19 presenting with dyspnea to the ED.

METHODS

In this retrospective observational study, clinical and demographic details of patients with COVID-19 were obtained at ED admission. S/F, ROX, NEWS, CRB-65, and qSOFA scores were calculated at the time of ED arrival. Accuracy of these five indices to predict the need for invasive mechanical ventilation (IMV) within 48 h, intensive care unit (ICU) admission, and early (7-day) mortality were determined using receiver operating characteristic curves.

RESULTS

A total of 375 patients were included in this study. Fifty patients (13.3%) required IMV within 48 h and 58 patients (15.5%) were transferred to the ICU. Seven-day mortality was 6.7% and 28-day mortality was 18.1%. Among all five scores determined from patient data on ED admission, ROX, S/F, and NEWS presented greater discriminatory performance than CRB-65 and qSOFA in predicting IMV within 48 h, ICU admission, and early mortality.

CONCLUSIONS

Emergency physicians can effectively use S/F, ROX, and NEWS scores for rapid risk stratification of patients with COVID-19 infection. Moreover, from the perspective of simplicity and ease of calculation, we recommend the use of the S/F ratio.

Prognostic Performance of Bedside Lung Ultrasound Score (LUSS) and ROX Index in Hypoxemic Respiratory Failure Due to COVID-19

Background: Noninvasive ventilation, mainly helmet CPAP, was widely used during the COVID-19 pandemic, even outside of intensive care units. Both the ROX index and the LUS score (LUSS) have been proposed as tools to predict negative outcomes in patients with hypoxemia treated with noninvasive ventilation (NIV) outside of ICUs. We aim to evaluate whether the combination of LUSS with the ROX index improves the predictive performance of these indices in patients with hypoxemia due to COVID-19 pneumonia, treated with NIV outside of ICUs. Methods: This is a monocentric prospective observational study conducted at the university teaching hospital Fondazione IRCCS San Gerardo dei Tintori (Monza, Italy) from February to April 2021. LUSS and ROX were collected at the same time in noninvasively ventilated patients outside of the ICU. An LUS exam was performed by 3 emergency medicine attending physicians with at least 5 years' experience in point-of-care ultrasonography using a 12-zone system. To evaluate the accuracy of the prognostic indices in predicting a composite outcome (endotracheal intubation and mortality), ROC curves were used. A logistic multivariable model was used to explore the predictors of the composite outcome of endotracheal intubation and in-hospital mortality. An unadjusted Kaplan-Meier analysis was used to explore the association with the composite outcome of survival without invasive mechanical ventilation at the 30-day follow-up by stratifying the 3 indices by their best cut-offs. Results: A total of 79 patients were included in the statistical analysis and stratified into 2 groups based on the presence of a negative outcome, which was reported in 24 patients out of 79 (30%). A great proportion of patients (66 patients-84%) were treated with helmet CPAP. All three indices (LUSS, ROX and LUSS/ROX) were independently associated with negative outcomes in the multivariable analyses. Although the comparison between the AUROC of LUSS or ROX versus LUSS/ROX did not reveal a statistically significant difference, we observed a trend toward a higher accuracy for predicting negative outcomes using the LUSS/ROX index as compared to using LUSS. With the Kaplan-Maier approach, all three indices stratified by the best cut-off reported a significant association with the outcome of 30-day survival without mechanical ventilation. Conclusions: A multimodal noninvasive approach that combines ultrasound (i.e., LUSS) and a bedside clinical evaluation (i.e., the ROX index) may help clinicians to predict outcomes and to identify patients who would benefit the most from invasive respiratory support.

The ROX index has greater predictive validity than NEWS2 for deterioration in Covid-19

BACKGROUND

Patients admitted to hospital with Covid-19 are at risk of deterioration. The National Early Warning Score (NEWS2) is widely recommended, however it's validity in Covid-19 is not established and indices more specific for respiratory failure may be more appropriate. We aim to describe the physiological antecedents to deterioration, test the predictive validity of NEWS2 and compare this to the ROX index ([SpO2/FiO2]/respiratory rate).

METHOD

A single centre retrospective cohort study of adult patients who were admitted to a medical ward, between 1/3/20 and 30/5/20, with positive results for SARS-CoV-2 RNA. Physiological observations and the NEWS2 were extracted and analysed. The primary outcome was a composite of cardiac arrest, unplanned critical care admission or death within 24 hours. A generalized linear model was used to assess the association of physiological values, NEWS2 and ROX with the outcome.

FINDINGS

The primary outcome occurred in 186 patients (26%). In the preceding 24 hours, deterioration was most marked in respiratory parameters, specifically in escalating oxygen requirement; tachypnoea was a late sign, whilst cardiovascular observations remained stable. The area under the receiver operating curve was 0.815 (95% CI 0.804-0.826) for NEWS2 and 0.848 (95% CI 0.837-0.858) for ROX. Applying the optimal level of ROX, the majority of patients triggered four hours earlier than with NEWS2 of 5.

INTERPRETATION

NEWS2 may under-perform in Covid-19 due to intrinsic limitations of the design and the unique pathophysiology of the disease. A simple index utilising respiratory parameters can outperform NEWS2 in predicting the occurrence of adverse events.

The ROX index can be a useful tool for the triage evaluation of COVID-19 patients with dyspnoea

Aim

To assess whether the application of a non‐invasive tool, such as ratio of oxygen saturation (ROX) index, during triage can identify patients with COVID‐19 at high risk of developing acute respiratory distress syndrome (ARDS).

Design

A multi‐centre, observational, retrospective study.

Methods

Only COVID‐19 positive patients who required an emergency department evaluation for dyspnoea were considered. The primary objective of the study was to compare the ROX value obtained during triage with the medical diagnosis of ARDS and intubation in 72 h of the triage evaluation. The ROX index value was also compared with objective outcomes, such as the pressure of arterial O₂ (PaO₂)/fraction of inspired oxygen (FiO₂) ratio and the lung parenchyma volume involved in COVID‐19‐related inflammatory processes, based on 3D reconstructions of chest computed tomography (CT).

Results

During the study period, from 20 March 2020 until 31 May 2020, a total of 273 patients with confirmed SARS‐CoV‐2 infection were enrolled. The predictive ability of ROX for the risk of developing ARDS in 72 h after triage evaluation was associated with an area under the receiver operating characteristic (AUROC) of 0.845 (0.797–0.892, p < 0.001), whereas the AUROC value was 0.727 (0.634–0.821, p < 0.001) for the risk of intubation. ROX values were strongly correlated with PaO₂/FiO₂ values (r = 0.650, p < 0.001), decreased ROX values were associated with increased percentages of lung involvement based on 3D CT reconstruction (r = −0.371, p < 0.001).

Conclusion

The ROX index showed a good ability to identify triage patients at high evolutionary risk. Correlations with objective but more invasive indicators (PaO₂/FiO₂ and CT) confirmed the important role of ROX in identifying COVID‐19 patients with extensive pathological processes.

Impact

During the difficult triage evaluation of COVID‐19 patients, the ROX index can help the nurse to identify the real severity of the patient. The triage systems could integrate the ROX in the rapid patient assessment to stratify patients more accurately.

A Novel Risk-Stratification Models of the High-Flow Nasal Cannula Therapy in COVID-19 Patients With Hypoxemic Respiratory Failure

Background: High-flow nasal cannula (HFNC) has been recommended as a suitable choice for the management of coronavirus disease 2019 (COVID-19) patients with acute hypoxemic respiratory failure before mechanical ventilation (MV); however, delaying MV with HFNC therapy is still a dilemma between the technique and clinical management during the ongoing pandemic.

Methods: Retrospective analysis of COVID-19 patients treated with HFNC therapy from four hospitals of Wuhan, China. Demographic information and clinical variables before, at, and shortly after HFNC initiation were collected and analyzed. A risk-stratification model of HFNC failure (the need for MV) was developed with the 324 patients of Jin Yin-tan Hospital and validated its accuracy with 69 patients of other hospitals.

Results: Among the training cohort, the median duration of HFNC therapy was 6 (range, 3–11), and 147 experienced HFNC failure within 7 days of HFNC initiation. Early predictors of HFNC failure on the basis of a multivariate regression analysis included age older than 60 years [odds ratio (OR), 1.93; 95% confidence interval (CI), 1.08–3.44; p = 0.027; 2 points], respiratory rate-oxygenation index (ROX) <5.31 (OR, 5.22; 95% CI, 2.96–9.20; p < 0.001; 5 points) within the first 4 h of HFNC initiation, platelets < 125 × 10⁹/L (OR, 3.04; 95% CI, 1.46–6.35; p = 0.003; 3 points), and interleukin 6 (IL-6) >7.0 pg/mL (OR, 3.34; 95% CI, 1.79–6.23; p < 0.001; 3 points) at HFNC initiation. A weighted risk-stratification model of these predictors showed sensitivity of 80.3%, specificity of 71.2% and a better predictive ability than ROX index alone [area under the curve (AUC) = 0.807 vs. 0.779, p < 0.001]. Six points were used as a cutoff value for the risk of HFNC failure stratification. The HFNC success probability of patients in low-risk group (84.2%) was 9.84 times that in the high-risk group (34.8%). In the subsequent validation cohort, the AUC of the model was 0.815 (0.71–0.92).

Conclusions: Aged patients with lower ROX index, thrombocytopenia, and elevated IL-6 values are at increased risk of HFNC failure. The risk-stratification models accurately predicted the HFNC failure and early stratified COVID-19 patients with HFNC therapy into relevant risk categories.

Dual-labeled prostate-specific membrane antigen (PSMA)-targeting agent for preoperative molecular imaging and fluorescence-guided surgery for prostate cancer

The objective of this study was to report the synthesis and characteristics of a dual modality imaging agent, Tc-99m GRFLTGGTGRLLRIS-GHEG-ECG-K(-5-carboxy-X-rhodamine)-NH₂ (GRFLT-ECG-ROX), and to verify its feasibility as both molecular imaging and intraoperative guidance agent. GRFLT-ECG-ROX was synthesized using Fmoc solid-phase peptide synthesis. Radiolabeling of GRFLT-ECG-ROX with Tc-99m was accomplished using ligand exchange via tartrate. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution, and ex vivo imaging studies were performed using LNCaP and PC-3 tumor-bearing murine models. Surgical removal of tumor nodules in murine models with peritoneal carcinomatosis was performed under a fluorescence imaging system. After radiolabeling procedures with Tc-99m, Tc-99m GRFLT-ECG-ROX complexes were prepared in high yield (>96%). The binding affinity value (K_d ) of Tc-99m GRFLT-ECG-ROX for LNCaP cells was estimated to be 9.5 ± 1.3 nM. In gamma camera imaging, the tumor to normal muscle uptake ratios of Tc-99m GRFLT-ECG-ROX increased with time (3.1 ± 0.2, 4.0 ± 0.4, and 6.3 ± 0.9 at 1, 2, and 3 h, respectively). Under real-time optical imaging, the removal of visible nodules was successfully performed. Thus, Tc-99m GRFLT-ECG-ROX could provide both preoperative molecular imaging and fluorescence imaging guidance for tumor removal.

A novel dual-modality imaging agent targeting folate receptor of tumor for molecular imaging and fluorescence-guided surgery

OBJECTIVE

Folate receptor (FR) is an ideal target for cancer imaging because it is frequently overexpressed in major types of human tumor, whereas its expression in normal organs is highly limited. Combining nuclear and fluorescence-imaging techniques provides a novel approach for cancer imaging and monitoring the surgery. The objective of this study was to report the synthesis and characteristics of a dual-modality imaging agent, Tc-99m Folate-Gly-His-Glu-Gly-Glu-Cys-Gly-Lys(-5-carboxy-X-rhodamine)-NH₂ (Folate-ECG-ROX), and verify its feasibility as both molecular imaging agent and intra-operative guidance.

METHODS

Folate-ECG-ROX was synthesized using Fmoc solid-phase peptide synthesis. Radiolabeling of Folate-ECG-ROX with Tc-99m was done using ligand exchange via tartrate. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution and ex vivo imaging studies were performed using KB and HT-1080 tumor-bearing murine models. Tumor tissue slides were prepared and analyzed with immunohistochemistry staining and confocal microscopy. Surgical removal of tumor nodules in murine models with peritoneal carcinomatosis was performed under the fluorescence-imaging system.

RESULTS

After radiolabeling procedures with Tc-99m, Tc-99m Folate-ECG-ROX complexes were prepared in high yield (> 97%). The binding affinity value (K_d) of Tc-99m Folate-ECG-ROX for KB cells was estimated to be 6.9 ± 0.9 nM. In gamma camera imaging, tumor to normal muscle uptake ratio of Tc-99m Folate-ECG-ROX increased with time (3.4 ± 0.4, 4.4 ± 0.7, and 6.6 ± 0.8 at 1, 2, and 3 h, respectively). In biodistribution study, %IA/g for KB tumor was 2.50 ± 0.80 and 4.08 ± 1.16 at 1 and 3 h, respectively. Confocal microscopy with immunohistochemistry staining detected strong Tc-99m Folate-ECG-ROX fluorescence within KB tumor tissue which is correlating with the fluorescent activity of anti-FR antibody. Under real-time optical imaging, the removal of visible nodules was successfully performed.

CONCLUSIONS

In vivo and in vitro studies revealed substantial and specific uptake of Tc-99m Folate-ECG-ROX in FR-positive tumors. Thus, Tc-99m Folate-ECG-ROX could provide both pre-operative molecular imaging and fluorescence image-guidance for tumor.

Real-Time Reverse Transcription PCR as a Tool to Study Virulence Gene Regulation in Bacterial Pathogens

Quantitative real-time PCR (qRT-PCR) is a highly sensitive and reliable method for detection and quantification of DNA. When combined with a prior stage of RNA reverse transcription to generate complementary DNA (cDNA), this is a powerful approach to determine and analyze gene transcriptional expression. Real-time quantitative reverse transcription PCR has become the gold standard method in studying genes expression and virulence regulation under various genetic backgrounds (e.g., in the absence of regulators) or environmental conditions. Here we demonstrate the utilization of this approach to study the transcriptional regulation of the conjugation pilus of the Salmonella enterica serovar Infantis virulence plasmid (pESI).

Pharmaceuticals and personal care products in the aquatic environment in China: a review

Pharmaceuticals and personal care products (PPCPs) have been detected as contaminants of emerging concern ubiquitously in the aquatic environment in China and worldwide. A clear picture of PPCP contamination in the Chinese aquatic environment is needed to gain insight for both research and regulatory needs (e.g. monitoring, control and management). The occurrence data of 112 PPCPs in waters and sediments in China has been reviewed. In most cases, the detected concentration of these PPCPs in waters and sediments were at ng/L and ng/g levels, which were lower than or comparable to those reported worldwide. A screening level risk assessment (SLERA) identified six priority PPCPs in surface waters, namely erythromycin, roxithromycin, diclofenac, ibuprofen, salicylic acid and sulfamethoxazole. The results of SLERA also revealed that the hot spots for PPCP pollution were those river waters affected by the megacities with high density of population, such as Beijing, Tianjin, Guangzhou and Shanghai. Limitations of current researches and implications for future research in China were discussed. Some regulatory issues were also addressed.

High resolution respirometry analysis of polyethylenimine-mediated mitochondrial energy crisis and cellular stress: Mitochondrial proton leak and inhibition of the electron transport system

Polyethylenimines (PEIs) are highly efficient non-viral transfectants, but can induce cell death through poorly understood necrotic and apoptotic processes as well as autophagy. Through high resolution respirometry studies in H1299 cells we demonstrate that the 25kDa branched polyethylenimine (25k-PEI-B), in a concentration and time-dependent manner, facilitates mitochondrial proton leak and inhibits the electron transport system. These events were associated with gradual reduction of the mitochondrial membrane potential and mitochondrial ATP synthesis. The intracellular ATP levels further declined as a consequence of PEI-mediated plasma membrane damage and subsequent ATP leakage to the extracellular medium. Studies with freshly isolated mouse liver mitochondria corroborated with bioenergetic findings and demonstrated parallel polycation concentration- and time-dependent changes in state 2 and state 4o oxygen flux as well as lowered ADP phosphorylation (state 3) and mitochondrial ATP synthesis. Polycation-mediated reduction of electron transport system activity was further demonstrated in 'broken mitochondria' (freeze-thawed mitochondrial preparations). Moreover, by using both high-resolution respirometry and spectrophotometry analysis of cytochrome c oxidase activity we were able to identify complex IV (cytochrome c oxidase) as a likely specific site of PEI mediated inhibition within the electron transport system. Unraveling the mechanisms of PEI-mediated mitochondrial energy crisis is central for combinatorial design of safer polymeric non-viral gene delivery systems.