2021 Acute Respiratory Distress Syndrome Update, With Coronavirus Disease 2019 Focus

Novel Therapeutic Target for ALI/ARDS: Forkhead Box Transcription Factors

ALI/ARDS can be a pulmonary manifestation of a systemic inflammatory response or a result of overexpression of the body's normal inflammatory response involving various effector cells, cytokines, and inflammatory mediators, which regulate the body's immune response through different signalling pathways. Forkhead box transcription factors are evolutionarily conserved transcription factors that play a crucial role in various cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism, and DNA damage response. Transcription factors control protein synthesis by regulating gene transcription levels, resulting in diverse biological outcomes. The Fox family plays a role in activating or inhibiting the expression of various molecules related to ALI/ARDS through phosphorylation, acetylation/deacetylation, and control of multiple signalling pathways. An in-depth analysis of the integrated Fox family's role in ALI/ARDS can aid in the development of potential diagnostic and therapeutic targets for the condition.

Dexmedetomidine mitigates lipopolysaccharide-induced acute lung injury by modulating heat shock protein A12B to inhibit the toll-like receptor 4/nuclear factor-kappa B signaling pathway

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS): Life-threatening medical conditions characterized by high morbidity and mortality rates, where the inflammatory process plays a crucial role in lung tissue damage, especially in models induced by lipopolysaccharide (LPS). Heat shock protein A12B (HSPA12B) has strong anti-infammatory properties However, it is unknown whether increased HSPA12B is protective against LPS-induced ALI. And Dexmedetomidine (DEX) is a potent α2-adrenergic receptor (α2-AR) agonist that has been shown to protect against sepsis-induced lung injury, however, the underlying mechanisms of this protection are not fully understood. This study utilized bioinformatics analysis and an LPS-induced ALI model to explore how DEX alleviates lung injury by modulating HSPA12B and inhibiting the Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway. Results indicate that HSPA12B overexpression and DEX pre-treatment markedly mitigated LPS-induced lung injury, which was evaluated by the deterioration of histopathology, histologic scores, the W/D weight ratio, and total protein expression, tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β) in the BALF, and the levels of NO, MDA,SOD and MPO in the lung. Moreover, HSPA12B overexpression and DEX pre-treatment significantly reduces lung injury and inflammation levels by upregulating HSPA12B and inhibiting the activation of the TLR4/NF-κB signaling pathway. On the contrary, when the expression of HSPA12B is inhibited, the protective effect of DEX pre-treatment on lung tissue is significantly weakened.In summary, our research demonstrated that the increased expression of AAV-mediated HSPA12B in the lungs of mice inhibits acute inflammation and suppresses the activation of TLR4/NF-κB pathway in a murine model of LPS-induced ALI. DEX could enhance HSPA12B and inhibit the initiation and development of inflammation through down-regulating TLR4/NF-κB pathway.These findings highlight the potential of DEX as a therapeutic agent for treating ALI and ARDS, offering new strategies for clinical intervention.

Diterpene Coronarin Attenuates Lipopolysaccharide-Induced Acute Lung Injury in Both In Vivo and In Vitro Models

Acute lung injury (ALI) is a clinical condition occurs due to severe systemic inflammatory response for clinical stimulus like pneumonia, sepsis, trauma, aspiration, inhalation of toxic gases, and pancreatitis. Disruption of alveolar barriers, activation of macrophages, infiltration of neutrophils, and proinflammatory cytokines are the vital events occurs during ALI. The drugs which inhibit these inflammatory response can protect lungs from inflammatory insults. In this study, we examined the potency of phytochemical coronarin, a diterpene which have been proven to possess anti-inflammatory, antioxidant, antiangiogenic, and antitumor activities. Healthy BALB/c mice were induced to acute lung injury with intra-tracheal administration of LPS and then treated with 5 and 10 mg/kg concentration of coronarin. The wet/dry lung weight of mice were estimated to assess the induction of pulmonary edema. BALF fluid was analyzed for protein concentrations and immune cells count. Myeloperoxidase activity and levels of chemokines MCP-2 and MIP-2, iNOS, COX-2, and PGE-2 were quantified to assess the immunomodulatory effect of coronarin against LPS-induced ALI. The levels of proinflammatory cytokines was measured to examine the anti-inflammatory property of coronarin, and it was confirmed with histopathological analysis of the lung tissue. Murine RAW 264.7 cells were utilized for the in vitro analysis. Cell cytoxicity and cytoprotective property of coronarin was assessed with MTT assay in LPS-treated Murine RAW 264.7. The anti-inflammatory property of coronarin was further confirmed in in vitro condition by estimating the levels of pro-inflammatory cytokines in coronarin-treated and untreated LPS-induced cells. Overall, our in vivo and in vitro results confirm coronarin significantly inhibited the infiltration of neutrophils prevented immunodulatory activity and synthesis of proinflammatory cytokines and alleviated the acute lung injury induced by LPS. Coronarin is a potent anti-inflammatory drug which can be subjected to further research to be prescribed as drug for ALI.

Cerebral hemodynamics and optic nerve sheath diameter acquired via neurosonology in critical patients with severe coronavirus disease: experience of a national referral hospital in Peru

Aim

We aimed to describe the neurosonological findings related to cerebral hemodynamics acquired using transcranial Doppler and to determine the frequency of elevated ICP by optic nerve sheath diameter (ONSD) measurement in patients with severe coronavirus disease (COVID-19) hospitalized in the intensive care unit of a national referral hospital in Peru.

Methods

We included a retrospective cohort of adult patients hospitalized with severe COVID-19 and acute respiratory failure within the first 7 days of mechanical ventilation under deep sedoanalgesia, with or without neuromuscular blockade who underwent ocular ultrasound and transcranial Doppler. We determine the frequency of elevated ICP by measuring the diameter of the optic nerve sheath, choosing as best cut-off value a diameter equal to or >5.8 mm. We also determine the frequency of sonographic patterns obtained by transcranial Doppler. Through insonation of the middle cerebral artery. Likewise, we evaluated the associations of clinical, mechanical ventilator, and arterial blood gas variables with ONSD ≥5.8 mm and pulsatility index (PI) ≥1.1. We also evaluated the associations of hemodynamic findings and ONSD with mortality the effect size was estimated using Poisson regression models with robust variance.

Results

This study included 142 patients. The mean age was 51.39 ± 13.3 years, and 78.9% of patients were male. Vasopressors were used in 45.1% of patients, and mean arterial pressure was 81.87 ± 10.64 mmHg. The mean partial pressure of carbon dioxide (PaCO2) was elevated (54.08 ± 16.01 mmHg). Elevated intracranial pressure was seen in 83.1% of patients, as estimated based on ONSD ≥5.8 mm. A mortality rate of 16.2% was reported. In the multivariate analysis, age was associated with elevated ONSD (risk ratio [RR] = 1.07). PaCO2 was a protective factor (RR = 0.64) in the cases of PI ≥ 1.1. In the mortality analysis, the mean velocity was a risk factor for mortality (RR = 1.15).

Conclusions

A high rate of intracranial hypertension was reported, with ONSD measurement being the most reliable method for estimation. The increase in ICP measured by ONSD in patients with severe COVID-19 on mechanical ventilation is not associated to hypercapnia or elevated intrathoracic pressures derived from protective mechanical ventilation.

Inhibition of GBP5 activates autophagy to alleviate inflammatory response in LPS-induced lung injury in mice

BACKGROUND

Pulmonary emphysema is a condition that causes damage to the lung tissue over time. GBP5, as part of the guanylate-binding protein family, is dysregulated in mouse pulmonary emphysema. However, the role of GBP5 in lung inflammation in ARDS remains unveiled.

METHODS

To investigate whether GBP5 regulates lung inflammation and autophagy regulation, the study employed a mouse ARDS model and MLE-12 cell culture. Vector transfection was performed for the genetic manipulation of GBP5. Then, RT-qPCR, WB and IHC staining were conducted to assess its transcriptional and expression levels. Histological features of the lung tissue were observed through HE staining. Moreover, ELISA was conducted to evaluate the secretion of inflammatory cytokines, autophagy was assessed by immunofluorescent staining, and MPO activity was determined using a commercial kit.

RESULTS

Our study revealed that GBP5 expression was altered in mouse ARDS and LPS-induced MLE-12 cell models. Moreover, the suppression of GBP5 reduced lung inflammation induced by LPS in mice. Conversely, overexpression of GBP5 diminished the inhibitory impact of LPS on ARDS during autophagy, leading to increased inflammation. In the cell line of MLE-12, GBP5 exacerbates LPS-induced inflammation by blocking autophagy.

CONCLUSION

The study suggests that GBP5 facilitates lung inflammation and autophagy regulation. Thus, GBP5 could be a potential therapeutic approach for improving ARDS treatment outcomes, but further research is required to validate these findings.

Decreased LPS-induced lung injury in pigs treated with a lung surfactant protein A-derived nonapeptide that inhibits peroxiredoxin 6 activity and subsequent NOX1,2 activation

This study addressed the efficacy of a liposome-encapsulated nine amino acid peptide [peroxiredoxin 6 PLA2 inhibitory peptide-2 (PIP-2)] for the prevention or treatment of acute lung injury (ALI) +/- sepsis. PIP-2 inhibits the PLA2 activity of peroxiredoxin 6 (Prdx6), thereby preventing rac release and activation of NADPH oxidases (NOXes), types 1 and 2. Female Yorkshire pigs were infused intravenously with lipopolysaccharide (LPS) + liposomes (untreated) or LPS + PIP-2 encapsulated in liposomes (treated). Pigs were mechanically ventilated and continuously monitored; they were euthanized after 8 h or earlier if preestablished humane endpoints were reached. Control pigs (mechanical ventilation, no LPS) were essentially unchanged over the 8 h study. LPS administration resulted in systemic inflammation with manifestations of clinical sepsis-like syndrome, decreased lung compliance, and a marked decrease in the arterial Po2 with vascular instability leading to early euthanasia of 50% of untreated animals. PIP-2 treatment significantly reduced the requirement for supportive vasopressors and the manifestations of lung injury so that only 25% of animals required early euthanasia. Bronchoalveolar lavage fluid from PIP-2-treated versus untreated pigs showed markedly lower levels of total protein, cytokines (TNF-α, IL-6, IL-1β), and myeloperoxidase. Thus, the porcine LPS-induced sepsis-like model was associated with moderate to severe lung pathophysiology compatible with ALI, whereas treatment with PIP-2 markedly decreased lung injury, cardiovascular instability, and early euthanasia. These results indicate that inhibition of reactive oxygen species (ROS) production via NOX1/2 has a beneficial effect in treating pigs with LPS-induced ALI plus or minus a sepsis-like syndrome, suggesting a potential role for PIP-2 in the treatment of ALI and/or sepsis in humans.NEW & NOTEWORTHY Currently available treatments that can alter lung inflammation have failed to significantly alter mortality of acute lung injury (ALI). Peroxiredoxin 6 PLA2 inhibitory peptide-2 (PIP-2) targets the liberation of reactive O2 species (ROS) that is associated with adverse cell signaling events, thereby decreasing the tissue oxidative injury that occurs early in the ALI syndrome. We propose that treatment with PIP-2 may be effective in preventing progression of early disease into its later stages with irreversible lung damage and relatively high mortality.

Mitochondrial network dynamics in pulmonary disease: Bridging the gap between inflammation, oxidative stress, and bioenergetics

Once thought of in terms of bioenergetics, mitochondria are now widely accepted as both the orchestrator of cellular health and the gatekeeper of cell death. The pulmonary disease field has performed extensive efforts to explore the role of mitochondria in regulating inflammation, cellular metabolism, apoptosis, and oxidative stress. However, a critical component of these processes needs to be more studied: mitochondrial network dynamics. Mitochondria morphologically change in response to their environment to regulate these processes through fusion, fission, and mitophagy. This allows mitochondria to adapt their function to respond to cellular requirements, a critical component in maintaining cellular homeostasis. For that reason, mitochondrial network dynamics can be considered a bridge that brings multiple cellular processes together, revealing a potential pathway for therapeutic intervention. In this review, we discuss the critical modulators of mitochondrial dynamics and how they are affected in pulmonary diseases, including chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), acute lung injury (ALI), and pulmonary arterial hypertension (PAH). A dysregulated mitochondrial network plays a crucial role in lung disease pathobiology, and aberrant fission/fusion/mitophagy pathways are druggable processes that warrant further exploration. Thus, we also discuss the candidates for lung disease therapeutics that regulate mitochondrial network dynamics.

Investigating the Association Between Dynamic Driving Pressure and Mortality in COVID-19-Related Acute Respiratory Distress Syndrome: A Joint Modeling Approach Using Real-Time Continuously-Monitored Ventilation Data

IMPORTANCE AND OBJECTIVES

COVID-19-related acute respiratory distress syndrome (ARDS) is associated with high mortality and often necessitates invasive mechanical ventilation (IMV). Previous studies on non-COVID-19 ARDS have shown driving pressure to be robustly associated with ICU mortality; however, those studies relied on "static" driving pressure measured periodically and manually. As "continuous" automatically monitored driving pressure is becoming increasingly available and reliable with more advanced mechanical ventilators, we aimed to examine the effect of this "dynamic" driving pressure in COVID-19 ARDS throughout the entire ventilation period.

DESIGN SETTING AND PARTICIPANTS

This retrospective, observational study cohort study evaluates the association between driving pressure and ICU mortality in patients with concurrent COVID-19 and ARDS using multivariate joint modeling. The study cohort (n = 544) included all adult patients (≥ 18 yr) with COVID-19 ARDS between March 1, 2020, and April 30, 2021, on volume-control mode IMV for 12 hours or more in a Mass General Brigham, Boston, MA ICU.

MEASUREMENTS AND MAIN RESULTS

Of 544 included patients, 171 (31.4%) died in the ICU. Increased dynamic ΔP was associated with increased risk in the hazard of ICU mortality (hazard ratio [HR] 1.035; 95% credible interval, 1.004-1.069) after adjusting for other relevant dynamic respiratory biomarkers. A significant increase in risk in the hazard of death was found for every hour of exposure to high intensities of driving pressure (≥ 15 cm H2O) (HR 1.002; 95% credible interval 1.001-1.003).

CONCLUSIONS

Limiting patients' exposure to high intensities of driving pressure even while under lung-protective ventilation may represent a critical step in improving ICU survival in patients with COVID-19 ARDS. Time-series IMV data could be leveraged to enhance real-time monitoring and decision support to optimize ventilation strategies at the bedside.

Decreased PRESET-Score corresponds with improved survival in COVID-19 veno-venous extracorporeal membrane oxygenation

INTRODUCTION

The PREdiction of Survival on ECMO Therapy Score (PRESET-Score) predicts mortality while on veno-venous extracorporeal membrane oxygenation (VV ECMO) for acute respiratory distress syndrome. The aim of our study was to assess the association between PRESET-Score and survival in a large COVID-19 VV ECMO cohort.

METHODS

This was a single-center retrospective study of COVID-19 VV ECMO patients from 15 March 2020, to 30 November 2021. Univariable and Multivariable analyses were performed to assess patient survival and score differences.

RESULTS

A total of 105 patients were included in our analysis with a mean PRESET-Score of 6.74. Overall survival was 65.71%. The mean PRESET-Score was significantly lower in the survivor group (6.03 vs 8.11, p < 0.001). Patients with a PRESET-Score less than or equal to six had improved survival compared to those with a PRESET-Score greater than or equal to 8 (97.7% vs. 32.5%, p < 0.001). In a multivariable logistic regression, a lower PRESET-Score was also predictive of survival (OR 2.84, 95% CI 1.75, 4.63, p < 0.001).

CONCLUSION

We demonstrate that lower PRESET scores are associated with improved survival. The utilization of this validated, quantifiable, and objective scoring system to help identify COVID-19 patients with the greatest potential to benefit from VV-ECMO appears feasible. The incorporation of the PRESET-Score into institutional ECMO candidacy guidelines can help insure and improve access of this limited healthcare resource to all critically ill patients.

The Efficacy of Nitric Oxide-Generating Lozenges on Outcome in Newly Diagnosed COVID-19 Patients of African American and Hispanic Origin

BACKGROUND

The study was initiated in 2020 to test the efficacy of a nitric oxide-generating lozenge (NOL) in outpatients with newly diagnosed COVID-19 to mitigate disease severity. The study enrolled high-risk patients, African American and Latino.

METHODS

This was a randomized, double-blinded, prospective, placebo-controlled trial. The primary endpoint was hospitalization, intensive care unit admission, intubation, dialysis, and death. The secondary endpoints were time to symptom resolution and the effect on oxygen saturation. Patients ages 50-85 years with recent COVID-19 diagnosis with at least one risk factor were recruited. Patients were randomized to either active treatment or placebo using block randomization. Blood pressure and oxygen saturation (SpO2) was measured prior to and after the first dose and each morning thereafter.

RESULTS

A total of 840 patients was planned, half in each of the lozenge and placebo groups. An interim review of data was prespecified. Of 524 patients, the composite endpoint occurred in 6 patients, 3 (1.1%) in each group. The time to symptom resolution was 1 day shorter on active treatment (8.7 ± 6.6 vs 9.8 ± 6.8 days) (P = .3). There was no change in SpO2 on placebo (0.0 ± 2.0%) and no significant change on treatment (0.14 ± 0.9%), P = .3. All events occurred in the first year (2020).

CONCLUSIONS

This study did not find a benefit of NOL therapy in COVID-19 patients and was terminated for futility. NOL treatment did not reduce mortality, hospitalization, intubation, or a reduction in symptoms duration. The study did find the NO lozenges were well tolerated in high-risk patients, without reported side effects.

Circulating Surfactant Protein D: A Biomarker for Acute Lung Injury?

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening lung diseases in critically ill patients. The lack of prognostic biomarkers has halted detection methods and effective therapy development. Quantitative biomarker-based approaches in the systemic circulation have been proposed as a means of enhancing diagnostic strategies as well as pharmacotherapy in a patient-specific manner. Pulmonary surfactants are complex mixtures made up of lipids and proteins, which are secreted into the alveolar space by epithelial type II cells under normal and pathological conditions. In this review, we summarize the current knowledge of SP-D in lung injury from both preclinical and clinical studies. Among surfactant proteins, surfactant protein-D (SP-D) has been more widely studied in ALI and ARDS. Recent studies have reported that SP-D has a superior discriminatory ability compared to other lung epithelial proteins for the diagnosis of ARDS, which could reflect the severity of lung injury. Furthermore, we shed light on recombinant SP-D treatment and its benefits as a potential drug for ALI, and we encourage further studies to translate SP-D into clinical use for diagnosis and treatment.

Body mass index does not impact survival in COVID-19 patients requiring veno-venous extracorporeal membrane oxygenation

INTRODUCTION

With the increased demand for veno-venous extracorporeal membrane oxygenation (VV ECMO) during the COVID-19 pandemic, guidelines for patient candidacy have often limited this modality for patients with a body mass index (BMI) less than 40 kg/m2. We hypothesize that COVID-19 VV ECMO patients with at least class III obesity (BMI ≥ 40) have decreased in-hospital mortality when compared to non-COVID-19 and non-class III obese COVID-19 VV ECMO populations.

METHODS

This is a single-center retrospective study of COVID-19 VV ECMO patients from January 1, 2014, to November 30, 2021. Our institution used BMI ≥ 40 as part of a multi-disciplinary VV ECMO candidate screening process in COVID-19 patients. BMI criteria were not considered for exclusion criteria in non-COVID-19 patients. Univariate and multivariable analyses were performed to assess in-hospital mortality differences.

RESULTS

A total of 380 patients were included in our analysis: The COVID-19 group had a lower survival rate that was not statistically significant (65.7% vs.74.9%, p = .07). The median BMI between BMI ≥ 40 COVID-19 and non-COVID-19 patients was not different (44.5 vs 45.5, p = .2). There was no difference in survival between the groups (73.3% vs. 78.5%, p = .58), nor was there a difference in survival between the COVID-19 BMI ≥ 40 and BMI < 40 patients (73.3, 62.7, p= .29). Multivariable logistic regression with the outcome of in-hospital mortality was performed and BMI was not found to be significant (OR 0.99, 95% CI 0.89, 1.01; p = .92).

CONCLUSION

BMI ≥ 40 was not an independent risk factor for decreased in-hospital survival in this cohort of VV ECMO patients at a high-volume center. BMI should not be the sole factor when deciding VV ECMO candidacy in patients with COVID-19.

Sustained Treatment Response after Intravenous Cyclophosphamide in a Patient with Therapy-Resistant COVID-19 Acute Respiratory Distress Syndrome: A Case Report

Treatment of acute respiratory distress syndrome (ARDS) represents a severe complication of coronavirus disease 2019 (COVID-19) infection and is often challenging in intensive care treatment. Potential positive effects of intravenous cyclophosphamide have been reported in interstitial lung diseases (ILDs). However, there are no data on the use of high-dose cyclophosphamide in therapy-resistant COVID-19 ARDS. We report the case of a 32-year-old male patient admitted to the intensive care unit (ICU) of the Medical University of Vienna due to severe COVID-19 ARDS who required venovenous extracorporeal membrane oxygenation (ECMO) with a total runtime of 85 days. Despite all these therapeutic efforts, he remained in a condition of therapy-resistant ARDS. Unfortunately, the patient was denied for lung transplantation. However, a significant improvement in his respiratory condition was achieved after the administration of an intravenous regimen of cyclophosphamide and prednisolone. After a period of consecutive stabilization, the patient was transferred to the normal ward after 125 days of intensive care treatment. There is a substantial lack of therapeutic options in therapy-resistant ARDS. Our case report suggests that cyclophosphamide may represent a new treatment strategy in therapy-resistant ARDS. Due to its severe adverse effect profile, cyclophosphamide should be used after careful evaluation of a patient's general condition.

Staphylococcus aureus bacteremia in patients with SARS-CoV-2 infection

Objectives

The aim was to compare the incidence of Staphylococcus aureus bacteremia in COVID-19 and non-COVID-19 adult patients during the pandemic period versus the previous two years. Also, we described the characteristics of both cohorts of patients in pandemic period to find differences.

Material and methods

Retrospective study in our tertiary-care centre reviewing S. aureus bacteremia episodes in COVID-19 and non-COVID-19 patients through clinical records and the Microbiology Department database.

Results

In 2018 and 2019, the incidence of S. aureus bacteremia episodes was 1.95 and 1.63 per 1000 admissions respectively. In the pandemic period, global incidence was 1.96 episodes per 1000 non-COVID-19 admissions and 10.59 episodes per 1000 COVID-19 admissions. A total of 241 bacteremia was registered during this pandemic period in 74 COVID-19 patients and in 167 non-COVID-19 patients. Methicillin resistance was detected in 32.4% and 13.8% of isolates from COVID-19 and non-COVID-19 patients respectively. In COVID-19 patients, mortality rates were significantly higher.

Conclusions

We showed a significantly high rates of S. aureus bacteremia incidence in COVID-19 patients and higher methicillin resistance and 15-day mortality rates than in non-COVID-19 patients.

Same but Different? Comparing the Epidemiology, Treatments and Outcomes of COVID-19 and Non-COVID-19 ARDS Cases in Germany Using a Sample of Claims Data from 2021 and 2019

BACKGROUND

Acute respiratory distress syndrome (ARDS) is a severe lung condition that can be caused by a variety of underlying illnesses. Due to SARS-CoV-2, the number of cases with ARDS has increased worldwide, making it essential to compare this form of acute respiratory failure with classical causes of ARDS. While there have been several studies investigating the differences between COVID-19 and non-COVID-19 ARDS in early stages of the pandemic, little is known about the differences in later phases, especially in Germany.

AIM

The aim of this study is to characterize and compare the comorbidities, treatments, adverse events, and outcomes of COVID-19-associated ARDS and non-COVID-19 ARDS using a representative sample of German health claims data from the years 2019 and 2021.

METHODS

We compare percentages and median values of the quantities of interest from the COVID-19 and non-COVID-19 ARDS group, with p-values calculated after conducting Pearson's chi-squared test or the Wilcoxon rank sum test. We also run logistic regressions to access the effect of comorbidities on mortality for COVID-19 ARDS and non-COVID-19 ARDS.

RESULTS

Despite many similarities, we find that that there are some remarkable differences between COVID-19 and non-COVID-19 ARDS cases in Germany. Most importantly, COVID-19 ARDS cases display fewer comorbidities and adverse events, and are more often treated with non-invasive ventilation and nasal high-flow therapy.

CONCLUSIONS

This study highlights the importance of comprehending the contrasting epidemiological features and clinical outcomes of COVID-19 and non-COVID-19 ARDS. This understanding can aid in clinical decision making and guide future research initiatives aimed at enhancing the management of patients afflicted with this severe condition.

TIMP-1 and its potential diagnostic and prognostic value in pulmonary diseases

Tissue inhibitors of metalloproteases (TIMPs) have caught the attention of many scientists due to their role in various physiological and pathological processes. TIMP-1, 2, 3, and 4 are known members of the TIMPs family. TIMPs exert their biological effects by, but are not limited to, inhibiting the activity of metalloproteases (MMPs). The balance between MMPs and TIMPs is critical for maintaining homeostasis of the extracellular matrix (ECM), while the imbalance between MMPs and TIMPs can lead to pathological changes, such as cancer. In this review, we summarized the current knowledge of TIMP-1 in several pulmonary diseases namely, acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), pneumonia, asthma, chronic obstructive pulmonary disease (COPD), cystic fibrosis, and pulmonary fibrosis. Considering the potential of TIMP-1 serving as a non-invasive diagnostic and/or prognostic biomarker, we also reviewed the circulating TIMP-1 levels in translational and clinical studies.

Sedation with Sevoflurane versus Propofol in COVID-19 Patients with Acute Respiratory Distress Syndrome: Results from a Randomized Clinical Trial

BACKGROUND

Acute respiratory distress syndrome (ARDS) related to COVID-19 (coronavirus disease 2019) led to intensive care units (ICUs) collapse. Amalgams of sedative agents (including volatile anesthetics) were used due to the clinical shortage of intravenous drugs (mainly propofol and midazolam).

METHODS

A multicenter, randomized 1:1, controlled clinical trial was designed to compare sedation using propofol and sevoflurane in patients with ARDS associated with COVID-19 infection in terms of oxygenation and mortality.

RESULTS

Data from a total of 17 patients (10 in the propofol arm and 7 in the sevoflurane arm) showed a trend toward PaO₂/FiO₂ improvement and the sevoflurane arm's superiority in decreasing the likelihood of death (no statistical significance was found).

CONCLUSIONS

Intravenous agents are the most-used sedative agents in Spain, even though volatile anesthetics, such as sevoflurane and isoflurane, have shown beneficial effects in many clinical conditions. Growing evidence demonstrates the safety and potential benefits of using volatile anesthetics in critical situations.

Staphylococcus aureus bacteremia in patients with SARS-CoV-2 infection

OBJECTIVES

The aim was to compare the incidence of Staphylococcus aureus bacteremia in COVID-19 and non-COVID-19 adult patients during the pandemic period versus the previous two years. Also, we described the characteristics of both cohorts of patients in pandemic period to find differences.

MATERIAL AND METHODS

Retrospective study in our tertiary-care centre reviewing S. aureus bacteremia episodes in COVID-19 and non-COVID-19 patients through clinical records and the Microbiology Department database.

RESULTS

In 2018 and 2019, the incidence of S. aureus bacteremia episodes was 1.95 and 1.63 per 1000 admissions respectively. In the pandemic period, global incidence was 1.96 episodes per 1000 non-COVID-19 admissions and 10.59 episodes per 1000 COVID-19 admissions. A total of 241 bacteremia was registered during this pandemic period in 74 COVID-19 patients and in 167 non-COVID-19 patients. Methicillin resistance was detected in 32.4% and 13.8% of isolates from COVID-19 and non-COVID-19 patients respectively. In COVID-19 patients, mortality rates were significantly higher.

CONCLUSIONS

We showed a significantly high rates of S. aureus bacteremia incidence in COVID-19 patients and higher methicillin resistance and 15-day mortality rates than in non-COVID-19 patients.

Plasma TIMP-1 as a sex-specific biomarker for acute lung injury

BACKGROUND

Acute respiratory distress syndrome (ARDS) confers high morbidity and mortality, with a death rate reaching 40%. Pre-clinical and clinical studies have cited sex-specific sex hormones as a critical contributor to divergent immunologic responses. Therefore, exploration of sex and sex hormone roles following lung injury and ARDS development is needed. Tissue inhibitor of metalloproteinase-1 (TIMP-1) was the first-discovered natural collagenase inhibitor and is located exclusively on the X chromosome. This study aimed to evaluate the prognostic role of circulating TIMP-1, and if concentration differences between males and females correlate with the mortality of ARDS patients.

METHODS

Human plasma samples from 100 ARDS patients enrolled in Albuterol to Treat Acute Lung Injury (ALTA) trial on the day of randomization were evaluated. The amount of TIMP-1 was measured using an enzyme-linked immunoassay (ELISA). Area under the receiver operating characteristic (AUROC) was computed to assess the predictive power of TIMP-1 for 30 and 90-day mortality. Chi-squared tests and Kaplan-Meier curves were computed to assess different variables and survival.

RESULTS

AUROC analysis of TIMP-1 and 30-day mortality among females showed that TIMP-1 exhibited an AUC of 0.87 (95% confidence interval [CI] 0.78 to 0.97; P = 0.0014) with an optimal cut-off value of 159.7 ng/mL producing a 100% sensitivity and 74% specificity. For 90-day mortality, AUROC analysis showed an AUC of 0.82 (95% confidence interval [CI] 0.67 to 0.97; P = 0.0016) with a similar cut-off value producing a 90% sensitivity and 76.47% specificity. Stratifying subjects by TIMP-1 concentration as high (≥ 159.7 ng/mL) or low (< 159.7 ng/mL) indicated that high TIMP-1 was associated with increased 30 and 90-day mortality rates (all P < 0.0001). Lastly, high TIMP-1 group was associated with worse other outcomes including ventilator-free days (VFDs) and ICU-free days (all P < 0.05).

CONCLUSION

Circulating TIMP-1 appeared to be a promising biomarker for mortality among females with ARDS. The high TIMP-1 group showed worse VFDs and ICU-free days. Circulating TIMP-1 may be a sex-specific biomarker in the setting of ARDS and could improve ARDS phenotyping as well as provide a novel therapeutic target in females.

Outcomes of Surgical Tracheostomy on Mechanically Ventilated COVID-19 Patients Admitted to a Private Tertiary Hospital in Tanzania

OBJECTIVES

 The coronavirus disease 2019 (COVID-19) pandemic has resulted in an increase in the number of patients necessitating prolonged mechanical ventilation. Data on patients with COVID-19 undergoing tracheostomy indicating timing and outcomes are very limited. Our study illustrates--- outcomes for surgical tracheotomies performed on COVID-19 patients in Tanzania.

METHODS

 This was a retrospective observational study conducted at the Aga Khan Hospital in Dar es Salaam, Tanzania.

RESULTS

 Nineteen patients with COVID-19 underwent surgical tracheotomy between 16^th March and 31^st December 2021. All surgical tracheostomies were performed in the operating theatre. The average duration of intubation prior to tracheotomy and tracheostomy to ventilator liberation was 16 days and 27 days respectively. Only five patients were successfully liberated from the ventilator, decannulated, and discharged successfully.

CONCLUSIONS

 This is the first and largest study describing tracheotomy outcomes in COVID-19 patients in Tanzania. Our results revealed a high mortality rate. Multicenter studies in the private and public sectors are needed in Tanzania to determine optimal timing, identification of patients, and risk factors predictive of improved outcomes.

Evaluation of inhaled nitric oxide (iNO) treatment for moderate-to-severe ARDS in critically ill patients with COVID-19: a multicenter cohort study

Background

Inhaled nitric oxide (iNO) is used as rescue therapy in patients with refractory hypoxemia due to severe COVID-19 acute respiratory distress syndrome (ARDS) despite the recommendation against the use of this treatment. To date, the effect of iNO on the clinical outcomes of critically ill COVID-19 patients with moderate-to-severe ARDS remains arguable. Therefore, this study aimed to evaluate the use of iNO in critically ill COVID-19 patients with moderate-to-severe ARDS.

Methods

This multicenter, retrospective cohort study included critically ill adult patients with confirmed COVID-19 treated from March 01, 2020, until July 31, 2021. Eligible patients with moderate-to-severe ARDS were subsequently categorized into two groups based on inhaled nitric oxide (iNO) use throughout their ICU stay. The primary endpoint was the improvement in oxygenation parameters 24 h after iNO use. Other outcomes were considered secondary. Propensity score matching (1:2) was used based on the predefined criteria.

Results

A total of 1598 patients were screened, and 815 were included based on the eligibility criteria. Among them, 210 patients were matched based on predefined criteria. Oxygenation parameters (PaO₂, FiO₂ requirement, P/F ratio, oxygenation index) were significantly improved 24 h after iNO administration within a median of six days of ICU admission. However, the risk of 30-day and in-hospital mortality were found to be similar between the two groups (HR: 1.18; 95% CI: 0.77, 1.82; p = 0.45 and HR: 1.40; 95% CI: 0.94, 2.11; p= 0.10, respectively). On the other hand, ventilator-free days (VFDs) were significantly fewer, and  ICU and hospital LOS were significantly longer in the iNO group. In addition, patients who received iNO had higher odds of acute kidney injury (AKI) (OR (95% CI): 2.35 (1.30, 4.26), p value = 0.005) and hospital/ventilator-acquired pneumonia (OR (95% CI): 3.2 (1.76, 5.83), p value = 0.001).

Conclusion

In critically ill COVID-19 patients with moderate-to-severe ARDS, iNO rescue therapy is associated with improved oxygenation parameters but no mortality benefits. Moreover, iNO use is associated with higher odds of AKI, pneumonia, longer LOS, and fewer VFDs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04158-y.

Seasonal variation of the composition of essential oils from Piper cernuum Vell and Piper rivinoides Kunth, ADMET study, DFT calculations, molecular docking and dynamics studies of major components as potent inhibitors of the heterodimer methyltransferase complex NSP16-NSP10 SARS COV-2 protein

Coronavirus disease (COVID-19) has the virus that causes the SARS-CoV-2 severe acute respiratory syndrome, which has reached a pandemic proportion, with thousands of deaths worldwide already registered. It has no standardized effective clinical treatment, arousing the urgent need for the discovery of bioactive compounds for the treatment of symptoms of COVID-19. In this context, the present study aimed to evaluate the influence of seasonality on the yield and chemical composition of the essential oils of Piper cernuum and Piper rivinoides as well as to evaluate the anti-SARS-CoV-2 potential of the major components of each oil by molecular docking and quantum chemical calculation (Density Functional Theory method), being possible indicate that the winter and autumn periods, the seasons of the year where it is possible to obtain the highest percentage of Piper cernuum and Piper rivinoides oils, respectively. Regarding the anti-SARS-Cov-2 potential, the present work showed that the dihydroagarofuran present in Piper cernuum, presented a strong interaction with amino acid residues from Mpro, presenting a potential similar to Remdesivir, a drug for clinical use. Regarding methyltransferase, dihydroagarofuran (Piper cernuum) and myristicin (Piper rivinoids) showed better affinity, with important interactions at the active site of the inhibitor Sinefugin, suggesting a potential inhibitory effect of the heterodimer methyltransferase complex NSP16-NSP10 SARS Cov-2. Molecular docking and molecular dynamics studies represent an initial step, being indicative for future in vitro studies of dihydroagarofuran and myristicin, as possible pharmacological tools for COVID-19.

A computational evaluation of FDA medicines’ ability to inhibit hypoxia-inducible factor prolyl hydroxylase-2 (PHD-2) for acute respiratory distress syndrome

COVID-19 infection is associated with a significant fatality rate in individuals suffering from severe acute respiratory distress syndrome (ARDS). Among the several possibilities, inhibition of hypoxia-inducible factor prolyl hydroxylase-2 or prolyl hydroxylase domain-containing protein 2 (PHD2) in a hypoxia-independent way is a prospective therapeutic target for the treatment of ARDS. Vadadustat, Roxadustat, Daprodustat, Desidustat, and Enarudustat are the available clinical trial inhibitors. This study is proposed to focus on the repurposing of FDA-approved drugs as effective PHD2 inhibitors. This computational study utilises e-pharmacophore hypothesis generation from the native ligand–protein complex (PDB ID: 5OX6) based on XP visualiser information. The hypothesis containing five essential features (AAANR) was incorporated for FDA database screening, followed by Glide XP molecular docking and Prime MM-GBSA binding free energy calculations. Top scored ligands were investigated and Fenbufen was identified as an effective PHD-2 inhibitor by comparing with the native co-crystal ligand (Vadadustat). The manual lead optimisation of the Fenbufen structure was adopted to improve inhibitory potency, by increasing the binding affinity and protein–ligand stability. The newly designed compounds B and C showed additional binding interactions, excellent docking scores, binding free energy, and an acceptable range of ADME properties. Also, Fenbufen and compound C owned preferable protein–ligand stability during MD simulation when compared with the co-crystallised clinical trial ligand. Based on our findings, we deduce that Fenbufen can be proposed as an effective repurposable candidate as its structural modification showed a remarkable improvement in PHD2 inhibition.

Determination of IgG1 and IgG3 SARS-CoV-2 Spike Protein and Nucleocapsid Binding-Who Is Binding Who and Why?

The involvement of immunoglobulin (Ig) G3 in the humoral immune response to SARS-CoV-2 infection has been implicated in the pathogenesis of acute respiratory distress syndrome (ARDS) in COVID-19. The exact molecular mechanism is unknown, but it is thought to involve this IgG subtype’s differential ability to fix, complement and stimulate cytokine release. We examined the binding of convalescent patient antibodies to immobilized nucleocapsids and spike proteins by matrix-assisted laser desorption/ionization–time of flight (MALDI-ToF) mass spectrometry. IgG3 was a major immunoglobulin found in all samples. Differential analysis of the spectral signatures found for the nucleocapsid versus the spike protein demonstrated that the predominant humoral immune response to the nucleocapsid was IgG3, whilst for the spike protein it was IgG1. However, the spike protein displayed a strong affinity for IgG3 itself, as it would bind from control plasma samples, as well as from those previously infected with SARS-CoV-2, similar to the way protein G binds IgG1. Furthermore, detailed spectral analysis indicated that a mass shift consistent with hyper-glycosylation or glycation was a characteristic of the IgG3 captured by the spike protein.

Effects of Drugs Formerly Proposed for COVID-19 Treatment on Connexin43 Hemichannels

Connexin43 (Cx43) hemichannels form a pathway for cellular communication between the cell and its extracellular environment. Under pathological conditions, Cx43 hemichannels release adenosine triphosphate (ATP), which triggers inflammation. Over the past two years, azithromycin, chloroquine, dexamethasone, favipiravir, hydroxychloroquine, lopinavir, remdesivir, ribavirin, and ritonavir have been proposed as drugs for the treatment of the coronavirus disease 2019 (COVID-19), which is associated with prominent systemic inflammation. The current study aimed to investigate if Cx43 hemichannels, being key players in inflammation, could be affected by these drugs which were formerly designated as COVID-19 drugs. For this purpose, Cx43-transduced cells were exposed to these drugs. The effects on Cx43 hemichannel activity were assessed by measuring extracellular ATP release, while the effects at the transcriptional and translational levels were monitored by means of real-time quantitative reverse transcriptase polymerase chain reaction analysis and immunoblot analysis, respectively. Exposure to lopinavir and ritonavir combined (4:1 ratio), as well as to remdesivir, reduced Cx43 mRNA levels. None of the tested drugs affected Cx43 protein expression.

Inhaled Sedation for Invasively Ventilated COVID-19 Patients: A Systematic Review

Background: Volatile anesthetics were used as sedative agents in COVID-19 (Coronavirus Disease 2019) invasively ventilated patients for their potentially beneficial pharmacological effects and due to the temporary shortages of intravenous agents during the pandemic crisis. Methods: Online databases (PubMed, EMBASE, The Cochrane Central Register of Controlled Trial) and the “clinicaltrials.gov” website were searched for studies reporting the use of isoflurane, sevoflurane or desflurane. Results: We identified three manuscripts describing the beneficial effects of isoflurane on 41 COVID-19 patients with acute respiratory distress syndrome (ARDS) in Germany (n = 2) and in the USA (n = 1), in terms of reduction in the use of opioids and other sedatives. We also found a case report of two patients with transient nephrogenic diabetes insipidus, which started after 6 and 8 days of sevoflurane sedation. We identified two randomized controlled trials (RCTs; 92 patients overall), two observational studies (238 patients) on the use of volatile anesthetics in COVID-19 patients that were completed but not yet published, and one RCT interrupted for a low recruitment ratio (19 patients) and thus not published. We also identified five ongoing RCTs on the use of inhaled sedation in ARDS, which are also likely to be recruiting COVID-19 patients and which have currently enrolled a total of >1643 patients. Conclusion: Isoflurane was the most frequently used volatile agent in COVID-19 patients and allowed a reduction in the use of other sedative and analgesic drugs. Randomized evidence is building up and will be useful to confirm or challenge these findings.

The COVID-19 Patient in the Surgical Intensive Care Unit

COVID-19 continues to rampage around the world. Noncritical care-trained physicians may be deployed into the intensive care unit to manage these complex patients. Although COVID-19 is primarily a respiratory disease, it is also associated with significant pathology in the brain, heart, vasculature, lungs, gastrointestinal tract, and kidneys. This article provides an overview of COVID-19 using an organ-based, systematic approach.

The Prevalence of Acute Respiratory Distress Syndrome (ARDS) and Outcomes in Hospitalized Patients with COVID-19-A Study Based on Data from the Polish National Hospital Register

Acute respiratory distress syndrome (ARDS) is a serious complication of COVID-19. This study aimed to evaluate the prevalence of ARDS among patients hospitalized with COVID-19 in Poland as well as to characterize clinical outcomes in patients hospitalized with COVID-19-associated ARDS. This is a retrospective, secondary analysis of epidemiological data from 116,539 discharge reports on patients hospitalized with COVID-19 in Poland between March and December 2020. The overall prevalence of ARDS was 3.6%, respectively 2.9% among females, and 4.4% among males (p < 0.001). Of the 4237 patients hospitalized with COVID-19-associated ARDS, 3764 deaths were reported (88.8%). Participants aged 60 years and over had more than three times higher odds of COVID-19-associated ARDS. Men had higher odds of COVID-19-associated ARDS than women (OR = 1.55; 95% CI: 1.45–1.65; p < 0.001). Patients with COVID-19 and diabetes had higher odds of COVID-19-associated ARDS (OR = 1.16; 95% CI: 1.03–1.30; p = 0.01). Among patients with COVID-19-associated ARDS, older age, male sex (OR = 1.27; 95% CI: 1.03–1.56; p = 0.02), and presence of cardiovascular diseases (OR = 1.26; 95% CI: 1.00–1.59; p = 0.048) were significantly associated with the risk of in-hospital death. Among patients hospitalized with COVID-19 in Poland, the prevalence of ARDS was relatively low, but the in-hospital mortality rate in patients with COVID-19-associated ARDS was higher compared to other EU countries.

The Influence of Helminth Immune Regulation on COVID-19 Clinical Outcomes: Is it Beneficial or Detrimental?

Immunologically, chronic worm infections prevent themselves from strong immune responses by skewing the host response towards a T helper 2 (Th2) type. The regulatory response initiated by helminth infections is supposed to temper responses to non-helminth antigens including viral infections which will, in turn, alter the clinical outcomes of infections. In view of this, recent reports highlighted the possible negative associations of severe COVID-19 and helminth co-infections in helminth-endemic regions. As the pathology of COVID-19 is primarily mediated by an excessive immune response and subsequent cytokine storm, which contributes to the poor prognosis of COVID-19, helminth-driven immune modulation will hypothetically contribute to the less severe outcomes of COVID-19. Nevertheless, emerging reports also stated that COVID-19 and helminth co-infections may have more hidden outcomes than predictable ones. Herein, the current knowledge on the interaction of COVID-19 and helminth co-infections will be discussed.

Impact of High Serum Levels of MMP-7, MMP-9, TGF-β and PDGF Macrophage Activation Markers on Severity of COVID-19 in Obese-Diabetic Patients

OBJECTIVE

The aim of this study was to identify an association between the severity of COVID-19 in obese-diabetic patients and altered serum levels of MMP-7, MMP-9, TGF-β, and PDGF macrophage activation markers.

METHODOLOGY

The study included 70 COVID-19 patients, divided into two groups: Group 1 included: Obese COVID-19 patients with type 2 diabetes mellitus (T2D, n=22 patients) and group 2 included; non-obese, non-diabetic COVID-19 patients as an age- and sex-matched control group (n=48 patients). Serum levels of the tested biomarkers were measured by ELISA at admission and after one weak follow-up.

RESULTS

There was a significant reduction in the serum levels of LBP in obese-diabetic COVID-19 patients versus the control group (8.34±3.94 vs 20.78±7.61) (p 0.0001). Significant elevation of MMP-7, MMP-9, PDGF and TGF-β was detected in obese diabetic COVID-19 patients compared to the non-obese non-diabetic group: 1044.7±519.6 vs 405.6±164.1, 483.05±46.5 vs 173.31±76.26, 154.5±62.78 vs 39.77±21.52, and 603.05±258.82 vs 180.29±97.17, respectively. The serum levels of macrophage activation markers in obese-diabetic patients one week after admission revealed that patients with acute respiratory distress syndrome (ARDS) had significantly higher serum levels of MMP-7 and MMP-9 than non-ARDS patients (p 0.02 and p 0.01 respectively).

CONCLUSION

Macrophages were mainly polarized towards the M2 phenotype in obese-diabetic COVID-19 patients with significant upregulation of the pro-fibrotic markers MMP-7, MMP-9, PDGF, and TGF-β. Thus, high levels of MMP-7 and MMP-9 are associated with ARDS in severe COVID-19 disease among obese-diabetic patients.