Acute respiratory distress syndrome due to COVID-19. Clinical and prognostic features from a medical Critical Care Unit in Valencia, Spain

Gut microbiome dynamics and associations with mortality in critically ill patients

BACKGROUND

Critical illness and care within the intensive care unit (ICU) leads to profound changes in the composition of the gut microbiome. The impact of such changes on the patients and their subsequent disease course remains uncertain. We hypothesized that specific changes in the gut microbiome would be more harmful than others, leading to increased mortality in critically ill patients.

METHODS

This was a prospective cohort study of critically ill adults in the ICU. We obtained rectal swabs from 52 patients and assessed the composition the gut microbiome using 16 S rRNA gene sequencing. We followed patients throughout their ICU course and evaluated their mortality rate at 28 days following admission to the ICU. We used selbal, a machine learning method, to identify the balance of microbial taxa most closely associated with 28-day mortality.

RESULTS

We found that a proportional ratio of four taxa could be used to distinguish patients with a higher risk of mortality from patients with a lower risk of mortality (p = .02). We named this binarized ratio our microbiome mortality index (MMI). Patients with a high MMI had a higher 28-day mortality compared to those with a low MMI (hazard ratio, 2.2, 95% confidence interval 1.1-4.3), and remained significant after adjustment for other ICU mortality predictors, including the presence of the acute respiratory distress syndrome (ARDS) and the Acute Physiology and Chronic Health Evaluation (APACHE II) score (hazard ratio, 2.5, 95% confidence interval 1.4-4.7). High mortality was driven by taxa from the Anaerococcus (genus) and Enterobacteriaceae (family), while lower mortality was driven by Parasutterella and Campylobacter (genera).

CONCLUSIONS

Dysbiosis in the gut of critically ill patients is an independent risk factor for increased mortality at 28 days after adjustment for clinically significant confounders. Gut dysbiosis may represent a potential therapeutic target for future ICU interventions.

Smoking and pre-existing co-morbidities as risk factors for developing severity of COVID-19 infection: Evidence from a field hospital in a rural area of Bangladesh

Since August 2020; the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) in collaboration with UNICEF has been operating a COVID-19 field hospital at the Teknaf sub-district of Cox's Bazar in Bangladesh. This paper is focused on estimating the effects of a history of tobacco smoking and pre-existing co-morbidities on the severity of COVID-19 infection among adult patients admitted into the aforesaid hospital. We conducted a retrospective data analysis of COVID-19 adult patients hospitalized from August 27, 2020 to April 20, 2022. Based on inclusion criteria; a total of 788 admitted patients were included in the analysis. We conducted a Chi-squared test and Fisher's exact test for the categorical variables to see their associations. Multinomial logistic regression models were performed to explore the risk factors for the severity of COVID-19 infection. Among 788 patients, 18.4%, 18.8%, 13%, 7.1%, 3.4%, and 1.9% have had a history of smoking, hypertension, diabetes, chronic obstructive pulmonary disease (COPD), cardiovascular diseases (CVD), and asthma respectively. Overall, the mean age of the patients was 40.3 ± 16.4 years and 51% were female. In multivariate analysis, history of smoking and co-morbidities were identified as the risk factors for the severity of COVID-19 infection; the history of smoking was found linked with an increase in the risk of developing critical, severe, and moderate level of COVID-19 infection- notably 3.17 times (RRR = 3.17; 95% CI: 1.3-7.68), 2.98 times (RRR = 2.98; 95% CI: 1.87-4.76) and 1.96 times (RRR = 1.96; 95% CI: 1.25-3.08) respectively more than the patients who never smoked. It was evident that patients with at least one of the selected co-morbidities such as hypertension, diabetes, COPD, CVD, and asthma exhibited a significantly higher likelihood of experiencing severe illness of COVID-19 compared to patients without any co-morbidity. History of tobacco smoking and pre-existing co-morbidities were significantly associated with an increased severity of COVID-19 infection.

Immunomodulatory therapy for the management of critically ill patients with COVID-19: A narrative review

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic. Understanding the physiological and immunological processes underlying the clinical manifestations of COVID-19 is vital for the identification and rational design of effective therapies.

AIM

To describe the interaction of SARS-CoV-2 with the immune system and the subsequent contribution of hyperinflammation and abnormal immune responses to disease progression together with a complete narrative review of the different immunoadjuvant treatments used so far in COVID-19 and their indication in severe and life-threatening subsets.

METHODS

A comprehensive literature search was developed. Authors reviewed the selected manuscripts following the PRISMA recommendations for systematic review and meta-analysis documents and selected the most appropriate. Finally, a recommendation of the use of each treatment was established based on the level of evidence of the articles and documents reviewed. This recommendation was made based on the consensus of all the authors.

RESULTS

A brief rationale on the SARS-CoV-2 pathogenesis, immune response, and inflammation was developed. The usefulness of 10 different families of treatments related to inflammation and immunopathogenesis of COVID-19 was reviewed and discussed. Finally, based on the level of scientific evidence, a recommendation was established for each of them.

CONCLUSION

Although several promising therapies exist, only the use of corticosteroids and tocilizumab (or sarilumab in absence of this) have demonstrated evidence enough to recommend its use in critically ill patients with COVID-19. Endotypes including both, clinical and biological characteristics can constitute specific targets for better select certain therapies based on an individualized approach to treatment.

Predictive Factors of Extubation Failure in COVID-19 Mechanically Ventilated Patients

Purpose: We investigated whether COVID-19 patients on mechanical ventilation (MV) had a different extubation outcome compared to non-COVID-19 patients while identifying predictive factors of extubation failure in the former. Methods: A retrospective, single-center, and observational study was done on 216 COVID-19 patients admitted to an intensive care unit (ICU) between March 2020 and March 2021, aged ≥ 18 years, in use of invasive MV for more than 24 h, which progressed to weaning. The primary outcome that was evaluated was extubation failure during ICU stay. A statistical analysis was performed to evaluate the association of patient characteristics with extubation outcome, and a Poisson regression model determined the predictive value. Results: Seventy-seven patients were extubated; the mean age was 57.2 years, 52.5% were male, and their mean APACHE II score at admission was 17.8. On average, MV duration until extubation was 8.7 ± 3.7 days, with 14.9 ± 10.1 days of ICU stay and 24.6 ± 14.0 days with COVID-19 symptoms. The rate of extubation failure (ie, the patient had to be reintubated during their ICU stay) was 22.1% (n = 17), while extubation was successful in 77.9% (n = 60) of cases. Failure was observed in only 7.8% of cases when evaluated 48 hours after extubation. The mean reintubation time was 4.28 days. After adjusting the analysis for age, sex, during of symptoms, days under MV, dialysis, and PaO2/FiO2 ratio, some parameters independently predicted extubation failure: age ≥ 66 years (APR = 5.12 [1.35-19.46]; p = 0.016), ≥ 31 days of symptoms (APR = 5.45 [0.48-62.19]; p = 0.016), and need for dialysis (APR = 5.10 [2.00-13.00]; p = 0.001), while a PaO2/FiO2 ratio >300 decreased the probability of extubation failure (APR = 0.14 [0.04-0.55]; p = 0.005). The presence of three predictors (ie, age ≥ 66 years, time of symptoms ≥ 31 days, need of dialysis, and PaO2/FiO2 ratio < 200) increased the risk of extubation failure by a factor of 23.0 (95% CI, 3.34-158.5). Conclusion: COVID-19 patients had an extubation failure risk that was almost three times higher than non-COVID-19 patients, with the extubation of the former being delayed compared to the latter. Furthermore, an age ≥ 66 years, time of symptoms ≥ 31 days, need of dialysis, and PaO2/FiO2 ratio > 200 were independent predictors for extubation failure, and the presence of three of these characteristics increased the risk of failure by a factor of 23.0.

Immunotherapy and CRISPR Cas Systems: Potential Cure of COVID-19?

The COVID-19 has plunged the world into a pandemic that affected millions. The continually emerging new variants of concern raise the question as to whether the existing vaccines will continue to provide sufficient protection for individuals from SARS-CoV-2 during natural infection. This narrative review aims to briefly outline various immunotherapeutic options and discuss the potential of clustered regularly interspaced short palindromic repeat (CRISPR Cas system technology against COVID-19 treatment as specific cure. As the development of vaccine, convalescent plasma, neutralizing antibodies are based on the understanding of human immune responses against SARS-CoV-2, boosting human body immune responses in case of SARS-CoV-2 infection, immunotherapeutics seem feasible as specific cure against COVID-19 if the present challenges are overcome. In cell based therapeutics, apart from the high costs, risks and side effects, there are technical problems such as the production of sufficient potent immune cells and antibodies under limited time to treat the COVID-19 patients in mild conditions prior to progression into a more severe case. The CRISPR Cas technology could be utilized to refine the specificity and safety of CAR-T cells, CAR-NK cells and neutralizing antibodies against SARS-CoV-2 during various stages of the COVID-19 disease progression in infected individuals. Moreover, CRISPR Cas technology are proposed in hypotheses to degrade the viral RNA in order to terminate the infection caused by SARS-CoV-2. Thus personalized cocktails of immunotherapeutics and CRISPR Cas systems against COVID-19 as a strategy might prevent further disease progression and circumvent immunity escape.

Evaluation of Patients Treated in Intensıve Care Due to COVID-19: A Retrospective Study

Background

The aim of this study is to report the demographic characteristics, clinical features, treatment protocols, comorbidities, imaging findings, prognosis and factors affecting mortality in critically ill patients with coronavirus disease 2019 (COVID-19) in the intensive care unit.

Materials and Methods

This retrospective cohort study consists of adult (≥18 years old) patients hospitalized in a tertiary hospital intensive care unit of with COVID-19. The independent effects of possible factors identified in previous analyzes on survival were analyzed using univariate and multivariate logistic regression analysis.

Results

The mean age of all patients was 70.2 ± 13.9 years. Of the 200 patients, 139 (69.5%) had died. White blood cells (19.2 ± 76.1 × 10⁹ per L), neutrophil/lymphocyte ratio (15.4 ± 65.1), d-dimer (2,558.4 ± 4,574.2 ng/mL), ferritin (1,481.2 ± 4,447.4 μg/L) and C-reactive protein (CRP) (12.1 ± 11.9 mg/dL) levels were high at the time of admission. According to the results of univariate regression analysis; presence of additional disease (odds ratio [OR]: 3.837; P = 0.015), older age (OR: 1.027; P = 0.015), reverse transcriptase-polymerase chain reaction (RT-PCR) positivity (OR: 2.58; P = 0.019), higher heart rate (OR = 1.027; P = 0.028), higher APACHE II score (OR: 1.049; P = 0.012), higher sequential organ failure assessement (SOFA) score(OR: 1.479; P = 0.014), high d-dimer levels (OR: 3.180; P <0.001) and high CRP levels (OR: 1.035; P = 0.028) increases the risk of death. When patients with full data for all variables in the multivariate logistic regression model were evaluated; positive RT-PCR (OR=4.105; P = 0.005), older age (OR: 1.033; P = 0.024), higher heart rate (OR: 1.042; P = 0.006), higher (SOFA) score (OR: 1.477; P <0.001), high d-dimer levels at admission (OR: 3.459; P = 0.002) and diabetes mellitus (OR: 3.433; P = 0.035) increase the risk of death.

Conclusion

Mortality of critically ill patients with COVID-19 pneumonia was high (69.5%). Older patients and acute respiratory distress syndrome were at higher risk of death. High SOFA score, high d-dimer at admission, and presence of diabetes mellitus were associated with high mortality.

Recommendations for the management of critically ill patients with COVID-19 in Intensive Care Units

The COVID-19 pandemic has led to the admission of a high number of patients to the ICU, generally due to severe respiratory failure. Since the appearance of the first cases of SARS-CoV-2 infection, at the end of 2019, in China, a huge number of treatment recommendations for this entity have been published, not always supported by sufficient scientific evidence or with methodological rigor necessary. Thanks to the efforts of different groups of researchers, we currently have the results of clinical trials, and other types of studies, of higher quality. We consider it necessary to create a document that includes recommendations that collect this evidence regarding the diagnosis and treatment of COVID-19, but also aspects that other guidelines have not considered and that we consider essential in the management of critical patients with COVID-19. For this, a drafting committee has been created, made up of members of the SEMICYUC Working Groups more directly related to different specific aspects of the management of these patients.

[Management of infectious complications associated with coronavirus infection in severe patients admitted to ICU]

Infections have become one of the main complications of patients with severe SARS-CoV-2 pneumonia admitted in ICU. Poor immune status, frequent development of organic failure requiring invasive supportive treatments, and prolonged ICU length of stay in saturated structural areas of patients are risk factors for infection development. The Working Group on Infectious Diseases and Sepsis GTEIS of the Spanish Society of Intensive Medicine and Coronary Units SEMICYUC emphasizes the importance of infection prevention measures related to health care, the detection and early treatment of major infections in the patient with SARS-CoV-2 infections. Bacterial co-infection, respiratory infections related to mechanical ventilation, catheter-related bacteremia, device-associated urinary tract infection and opportunistic infections are review in the document.

[Recommendations for the management of critically ill patients with COVID-19 in Intensive Care Units]

La pandemia por COVID-19 ha provocado el ingreso de un elevado número de pacientes en UCI, generalmente por insuficiencia respiratoria severa. Desde la aparición de los primeros casos de infección por SARS-CoV-2, a finales de 2019, en China, se ha publicado una cantidad ingente de recomendaciones de tratamiento de esta entidad, no siempre respaldadas por evidencia científica suficiente ni con el rigor metodológico necesario. Gracias al esfuerzo de distintos grupos de investigadores, actualmente disponemos de resultados de ensayos clínicos, y otro tipo de estudios, de mayor calidad. Consideramos necesario realizar un documento que incluya recomendaciones que recojan estas evidencias en cuanto al diagnóstico y tratamiento de la COVID-19, pero también aspectos que otras guías no han contemplado y que consideramos fundamentales en el manejo del paciente crítico con COVID-19. Para ello se ha creado un comité redactor, conformado por miembros de los Grupos de Trabajo de SEMICYUC más directamente relacionados con diferentes aspectos específicos del manejo de estos pacientes.

Management of infectious complications associated with coronavirus infection in severe patients admitted to ICU

Infections have become one of the main complications of patients with severe SARS-CoV-2 pneumonia admitted in ICU. Poor immune status, frequent development of organic failure requiring invasive supportive treatments, and prolonged ICU length of stay in saturated structural areas of patients are risk factors for infection development. The Working Group on Infectious Diseases and Sepsis GTEIS of the Spanish Society of Intensive Medicine and Coronary Units SEMICYUC emphasizes the importance of infection prevention measures related to health care, the detection and early treatment of major infections in the patient with SARS-CoV-2 infections. Bacterial co-infection, respiratory infections related to mechanical ventilation, catheter-related bacteremia, device-associated urinary tract infection and opportunistic infections are review in the document.

A Machine-Generated View of the Role of Blood Glucose Levels in the Severity of COVID-19

SARS-CoV-2 started spreading toward the end of 2019 causing COVID-19, a disease that reached pandemic proportions among the human population within months. The reasons for the spectrum of differences in the severity of the disease across the population, and in particular why the disease affects more severely the aging population and those with specific preconditions are unclear. We developed machine learning models to mine 240,000 scientific articles openly accessible in the CORD-19 database, and constructed knowledge graphs to synthesize the extracted information and navigate the collective knowledge in an attempt to search for a potential common underlying reason for disease severity. The machine-driven framework we developed repeatedly pointed to elevated blood glucose as a key facilitator in the progression of COVID-19. Indeed, when we systematically retraced the steps of the SARS-CoV-2 infection, we found evidence linking elevated glucose to each major step of the life-cycle of the virus, progression of the disease, and presentation of symptoms. Specifically, elevations of glucose provide ideal conditions for the virus to evade and weaken the first level of the immune defense system in the lungs, gain access to deep alveolar cells, bind to the ACE2 receptor and enter the pulmonary cells, accelerate replication of the virus within cells increasing cell death and inducing an pulmonary inflammatory response, which overwhelms an already weakened innate immune system to trigger an avalanche of systemic infections, inflammation and cell damage, a cytokine storm and thrombotic events. We tested the feasibility of the hypothesis by manually reviewing the literature referenced by the machine-generated synthesis, reconstructing atomistically the virus at the surface of the pulmonary airways, and performing quantitative computational modeling of the effects of glucose levels on the infection process. We conclude that elevation in glucose levels can facilitate the progression of the disease through multiple mechanisms and can explain much of the differences in disease severity seen across the population. The study provides diagnostic considerations, new areas of research and potential treatments, and cautions on treatment strategies and critical care conditions that induce elevations in blood glucose levels.

Outpatient Management of COVID-19 Disease: A Holistic Patient-Centered Proposal Based on the Greek Experience

Novel coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a worldwide pandemic and affected more than 227 countries or territories, resulting in more than 179 million cases with over 3.890.00 deaths, as of June 25, 2021. The Hellenic Thoracic Society (HTS) during the second wave of COVID-19 pandemic released a guidance document for the management of patients with COVID-19 in the community and in hospital setting. In this review, with guidance the HTS document, we are discussing the outpatient management of COVID-19 patients, including the preventive measures, the patients' isolation and quarantine criteria of close contacts, the severity and risk stratification, including the decisions for advanced hospitalization, and the disease management at home in patients with mild disease and after hospital discharge for those with more severe disease.

Systematic review and meta-analysis of tocilizumab in persons with coronavirus disease-2019 (COVID-19)

We performed a meta-analysis to determine safety and efficacy of tocilizumab in persons with coronavirus disease-2019 (COVID-19). We searched PubMed, Web of Science and Medline using Boolean operators for studies with the terms coronavirus OR COVID-19 OR 2019-nCoV OR SARS-CoV-2 AND tocilizumab. Review Manager 5.4 was used to analyze data and the modified Newcastle-Ottawa and Jadad scales for quality assessment. We identified 32 studies in 11,487 subjects including three randomized trials and 29 cohort studies with a comparator cohort, including historical controls (N = 5), a matched cohort (N = 12), or concurrent controls (N = 12). Overall, tocilizumab decreased risk of death (Relative Risk [RR] = 0.74; 95% confidence interval [CI], 0.59, 0.93; P = 0.008; I² = 80%) but not of surrogate endpoints including ICU admission (RR = 1.40 [0.64,3.06]; P = 0.4; I² = 88%), invasive mechanical ventilation (RR = 0.83 [0.57,1.22]; P = 0.34; I² = 65%) or secondary infections (RR = 1.30 [0.97,1.74]; P = 0.08; I² = 65%) and increased interval of hospitalization of subjects discharged alive(mean difference [MD] = 2 days [<1, 4 days]; P = 0.006; I² = 0). RRs of death in studies with historical controls (RR = 0.28 [0.16,0.49; P < 0.001]; I² = 62%) or a matched cohort (RR = 0.68 [0.53, 0.87]; P = 0.002; I² = 42%) were decreased. In contrast, RRs of death in studies with a concurrent control (RR = 1.10 [0.77, 1.56]; P = 0.60; I² = 85%) or randomized (RR = 1.18 [0.57,2.44]; P = 0.66; I² = 0) were not decreased. A reduced risk of death was not confirmed in our analyses which questions safety and efficacy of tocilizumab in persons with COVID-19.