Extracorporeal membrane oxygenation for COVID-19-related acute respiratory distress syndrome: a narrative review.

A growing body of evidence supports the use of extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS) refractory to maximal medical therapy. ARDS may develop in a proportion of patients hospitalized for coronavirus disease 2019 (COVID-19) and ECMO may be used to manage patients refractory to maximal medical therapy to mitigate the risk of ventilator-induced lung injury and provide lung rest while awaiting recovery. The mortality of COVID-19-related ARDS was variously reassessed during the pandemic. Veno-venous (VV) ECMO was the default choice to manage refractory respiratory failure; however, with concomitant severe right ventricular dysfunction, venoarterial (VA) ECMO or mechanical right ventricular assist devices with extracorporeal gas exchange (Oxy-RVAD) were also considered. ECMO has also been used to manage special populations such as pregnant women, pediatric patients affected by severe forms of COVID-19, and, in cases with persistent and seemingly irreversible respiratory failure, as a bridge to successful lung transplantation. In this narrative review, we outline and summarize the most recent evidence that has emerged on ECMO use in different patient populations with COVID-19-related ARDS.

Extracorporeal CO2 Removal During Renal Replacement Therapy to Allow Lung-Protective Ventilation in Patients with COVID-19-Associated Acute Respiratory Distress Syndrome.

The aim of this retrospective multicenter observational study is to test the feasibility and safety of a combined extracorporeal CO2 removal (ECCO2R) plus renal replacement therapy (RRT) system to use an ultraprotective ventilator setting while maintaining (1) an effective support of renal function and (2) values of pH within the physiologic limits in a cohort of coronavirus infectious disease 2019 (COVID-19) patients. Among COVID-19 patients admitted to the intensive care unit of 9 participating hospitals, 27 patients with acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI) requiring invasive mechanical ventilation undergoing ECCO2R-plus-RRT treatment were included in the analysis. The treatment allowed to reduce VT from 6.0 ± 0.6 mL/kg at baseline to 4.8 ± 0.8, 4.6 ± 1.0, and 4.3 ± 0.3 mL/kg, driving pressure (ΔP) from 19.8 ± 2.5 cm H2O to 14.8 ± 3.6, 14.38 ± 4.1 and 10.2 ± 1.6 cm H2O after 24 hours, 48 hours, and at discontinuation of ECCO2R-plus-RRT (T3), respectively (p < 0.001). PaCO2 and pH remained stable. Plasma creatinine decreased over the study period from 3.30 ± 1.27 to 1.90 ± 1.30 and 1.27 ± 0.90 mg/dL after 24 and 48 hours of treatment, respectively (p < 0.01). No patient-related events associated with the extracorporeal system were reported. These data show that in patients with COVID-19-induced ARDS and AKI, ECCO2R-plus-RRT is effective in allowing ultraprotective ventilator settings while maintaining an effective support of renal function and values of pH within physiologic limits.

Extracorporeal CO2 Removal During Renal Replacement Therapy to Allow Lung-Protective Ventilation in Patients with COVID-19-Associated Acute Respiratory Distress Syndrome.

The aim of this retrospective multicenter observational study is to test the feasibility and safety of a combined extracorporeal CO2 removal (ECCO2R) plus renal replacement therapy (RRT) system to use an ultraprotective ventilator setting while maintaining (1) an effective support of renal function and (2) values of pH within the physiologic limits in a cohort of coronavirus infectious disease 2019 (COVID-19) patients. Among COVID-19 patients admitted to the intensive care unit of 9 participating hospitals, 27 patients with acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI) requiring invasive mechanical ventilation undergoing ECCO2R-plus-RRT treatment were included in the analysis. The treatment allowed to reduce VT from 6.0 ± 0.6 mL/kg at baseline to 4.8 ± 0.8, 4.6 ± 1.0, and 4.3 ± 0.3 mL/kg, driving pressure (ΔP) from 19.8 ± 2.5 cm H2O to 14.8 ± 3.6, 14.38 ± 4.1 and 10.2 ± 1.6 cm H2O after 24 hours, 48 hours, and at discontinuation of ECCO2R-plus-RRT (T3), respectively (p < 0.001). PaCO2 and pH remained stable. Plasma creatinine decreased over the study period from 3.30 ± 1.27 to 1.90 ± 1.30 and 1.27 ± 0.90 mg/dL after 24 and 48 hours of treatment, respectively (p < 0.01). No patient-related events associated with the extracorporeal system were reported. These data show that in patients with COVID-19-induced ARDS and AKI, ECCO2R-plus-RRT is effective in allowing ultraprotective ventilator settings while maintaining an effective support of renal function and values of pH within physiologic limits.

Acinetobacter baumannii Isolates from COVID-19 Patients in a Hospital Intensive Care Unit: Molecular Typing and Risk Factors.

Infections caused by Acinetobacter baumannii represent a major concern for intensive care unit (ICU) patients. However, the epidemiology of these infections among COVID-19 patients has not been fully explored. The aims of this study were (i) to characterize the clonal spread of A. baumannii among COVID-19 patients admitted to the ICU of the Umberto I hospital of Rome during the first year of the pandemic and (ii) to identify risk factors for its acquisition. Isolates were analysed by pulsed-field gel electrophoresis, and a multivariable regression model was constructed. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated. Overall, 193 patients were included, and 102 strains were analysed. All isolates had highly antibiotic-resistant profiles and derived from two genotypes. The cumulative incidence of A. baumannii acquisition (colonization or infection) was 36.8%. Patients with A. baumannii had higher mortality and length of stay. Multivariable analysis showed that previous carbapenem use was the only risk factor associated with A. baumannii acquisition (aOR: 4.15, 95% CI: 1.78-9.64). We documented substantial A. baumannii infections and colonization and high levels of clonal transmission. Given the limited treatment options, effective prevention and containment strategies to limit the spread of A. baumannii should be implemented.

Inpatient Mortality According to Level of Respiratory Support Received for Severe Acute Respiratory Syndrome Coronavirus 2 (Coronavirus Disease 2019) Infection: A Prospective Multicenter Study.

OBJECTIVES: To describe patients according to the maximum degree of respiratory support received and report their inpatient mortality due to coronavirus disease 2019. DESIGN: Analysis of patients in the Coracle registry from February 22, 2020, to April 1, 2020. SETTING: Hospitals in the Piedmont, Lombardy, Tuscany, and Lazio regions of Italy. PATIENTS: Nine-hundred forty-eight patients hospitalized for coronavirus disease 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 948 patients, 122 (12.87%) received invasive ventilation, 637 (67.19%) received supplemental oxygen only, and 189 (19.94%) received no respiratory support. The median (quartile 1-quartile 3) age was 65 years (54-76.59 yr), and there was evidence of differential respiratory treatment by decade of life (p = 0.0046); patients greater than 80 years old were generally not intubated. There were 606 men (63.9%) in this study, and they were more likely to receive respiratory support than women (p < 0.0001). The rate of in-hospital death for invasive ventilation recipients was 22.95%, 12.87% for supplemental oxygen recipients, and 7.41% for those who received neither (p = 0.0004). A sensitivity analysis of the 770 patients less than 80 years old revealed a lower, but similar mortality trend (18.02%, 8.10%, 5.23%; p = 0.0008) among the 14.42%, 65.71%, and 19.87% of patients treated with mechanical ventilation, supplemental oxygen only, or neither. Overall, invasive ventilation recipients who died were significantly older than those who survived (median age: 68.5 yr [60-81.36 yr] vs 62.5 yr [55.52-71 yr]; p = 0.0145). CONCLUSIONS: Among patients hospitalized for coronavirus disease 2019, 13% received mechanical ventilation, which was associated with a mortality rate of 23%.

Oral Bacteriotherapy in Patients With COVID-19: A Retrospective Cohort Study.

Background: Mounting evidence suggests SARS-CoV-2 may impact on host microbiota and gut inflammation, infecting intestinal epithelial cells. This possible link and its implications can be investigated by observing the effects of modulation of the microbial flora in patients with COVID-19. The aim of this study was to compare the rate of mortality, the need of ICU hospitalization and the length of hospitalization in patients with severe COVID-19 pneumonia who received the best available therapy (BAT) vs. patients treated with BAT and supplemented with oral bacteriotherapy. Methods: This retrospective, observational cohort study included 200 adults with severe COVID-19 pneumonia. All patients received therapeutic regimens including low molecular weight heparin plus one or more between hydroxychloroquine, azithromycin, antivirals, and Tocilizumab. Oral bacteriotherapy was used as complementary treatment. Results: Out of the 200 patients, 112 received BAT without oral bacteriotherapy, and 88 BAT with oral bacteriotherapy. Crude mortality was 22%. Eleven percent died in the group of patients treated with BAT plus oral bacteriotherapy vs. 30% subjects in the group of patients managed only with BAT (p < 0.001). By multivariate analysis, the age >65 years, CRP >41.8 mg/L, Platelets <150.000 mmc, and cardiovascular events were associated with the increased risk of mortality. Oral bacteriotherapy was an independent variable associated with a reduced risk for death. Despite large prospective trials are needed, this study highlights a possible role for oral bacteriotherapy in the management of patients hospitalized for COVID-19 pneumonia.

Acute Kidney Injury and COVID-19: A Picture from an Intensive Care Unit.

INTRODUCTION: Acute kidney injury (AKI) is a frequent complication in coronavirus disease 2019 (COVID-19) patients admitted to intensive care unit (ICU) for severe respiratory failure. The aim is to evaluate the rate of AKI, defined according to Kidney Disease: Improving Global Outcome guidelines, in a series of critical COVID-19 patients admitted to the ICU of a single tertiary teaching hospital. METHODS: From April to May 2020, all consecutive critically ill COVID-19 patients admitted to the ICU who did not meet exclusion criteria (length of ICU stay <48 h, ESRD requiring dialysis, and patients still hospitalized in ICU at the time of data analysis) were enrolled in this study. Patients were stratified according to the highest AKI stage attained during ICU stay. RESULTS: Sixty-one patients were included in the analysis. AKI was observed in 35/61 patients (57.4%): 25/35 episodes (71.4%) were observed within the first 7 days. AKI was classified as follows: 17.1% stage 1, 25.7% stage 2, and 57.2% stage 3. Fourteen out of 20 stage-3 patients required continuous renal replacement therapy (CRRT), mostly related to persistent oliguria. The overall ICU mortality was 68.9%, and it was higher in patients developing AKI if compared to no-AKI patients (p = 0.006). Renal function recovery of any grade was observed in 14 out of 35 AKI patients (40%). Among patients undergoing CRRT, 13 patients were still dialysis dependent at the time of death. CONCLUSION: In critical COVID-19 patients, ICU mortality is particularly high, especially in patients developing AKI. An accurate monitoring of renal function in early phases of respiratory failure should be ensured in order to timely apply any strategy aimed at limiting renal complications during ICU stay.

Von Willebrand factor with increased binding capacity is associated with reduced platelet aggregation but enhanced agglutination in COVID-19 patients: another COVID-19 paradox?

Patients with Coronavirus-associated disease-2019 (COVID-19) display alterations of the hemostatic system and the presence of a prothrombotic status frequently leading to vascular complications. However, the impact of COVID-19 on platelet activity, aggregation and agglutination still needs to be clarified. We measured total levels of von Willebrand factor (vWF) and vWF binding to the platelet glycoprotein (Gp) complex (GPIb-IX-V), in a cohort of COVID-19 patients admitted to the intensive care unit of our Institution. Moreover, we evaluated platelet aggregation in response to agonists (ADP, collagen, arachidonic acid) and platelet agglutination in response to ristocetin. We found that levels of vWF antigen and the active form of vWF binding to platelets (vWF:RCo), were markedly increased in these patients. These results were associated with higher agglutination rates induced by ristocetin, thereby indirectly indicating an increased capability of vWF to bind to platelets. Conversely, we found that platelet aggregation in response to both ADP and collagen was lower in COVID-19 patients compared to healthy volunteers. This study shows that COVID-19 is associated with increased vWF-induced platelet agglutination but reduced platelet responsivity to aggregation stimuli. Our findings have translational relevance since platelet adhesion to vWF may represent a marker to predict possible complications and better delineate therapeutic strategies in COVID-19 patients.

Ozone as adjuvant support in the treatment of COVID-19: A preliminary report of probiozovid trial.

The evaluation of new therapeutic resources against coronavirus disease 2019 (COVID-19) represents a priority in clinical research considering the minimal options currently available. To evaluate the adjuvant use of systemic oxygen-ozone administration in the early control of disease progression in patients with COVID-19 pneumonia. PROBIOZOVID is an ongoing, interventional, randomized, prospective, and double-arm trial enrolling patient with COVID-19 pneumonia. From a total of 85 patients screened, 28 were recruited. Patients were randomly divided into ozone-autohemotherapy group (14) and control group (14). The procedure consisted in a daily double-treatment with systemic Oxygen-ozone administration for 7 days. All patients were treated with ad interim best available therapy. The primary outcome was delta in the number of patients requiring orotracheal-intubation despite treatment. Secondary outcome was the difference of mortality between the two groups. Moreover, hematological parameters were compared before and after treatment. No differences in the characteristics between groups were observed at baseline. As a preliminary report we have observed that one patient for each group needed intubation and was transferred to ITU. No deaths were observed at 7-14 days of follow up. Thirty-day mortality was 8.3% for ozone group and 10% for controls. Ozone therapy did not significantly influence inflammation markers, hematology profile, and lymphocyte subpopulations of patients treated. Ozone therapy had an impact on the need for the ventilatory support, although did not reach statistical significance. Finally, no adverse events related to the use of ozone-autohemotherapy were reported. Preliminary results, although not showing statistically significant benefits of ozone on COVID-19, did not report any toxicity.

Inpatient Mortality According to Level of Respiratory Support Received for Severe Acute Respiratory Syndrome Coronavirus 2 (Coronavirus Disease 2019) Infection: A Prospective Multicenter Study.

OBJECTIVES: To describe patients according to the maximum degree of respiratory support received and report their inpatient mortality due to coronavirus disease 2019. DESIGN: Analysis of patients in the Coracle registry from February 22, 2020, to April 1, 2020. SETTING: Hospitals in the Piedmont, Lombardy, Tuscany, and Lazio regions of Italy. PATIENTS: Nine-hundred forty-eight patients hospitalized for coronavirus disease 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 948 patients, 122 (12.87%) received invasive ventilation, 637 (67.19%) received supplemental oxygen only, and 189 (19.94%) received no respiratory support. The median (quartile 1-quartile 3) age was 65 years (54-76.59 yr), and there was evidence of differential respiratory treatment by decade of life (p = 0.0046); patients greater than 80 years old were generally not intubated. There were 606 men (63.9%) in this study, and they were more likely to receive respiratory support than women (p < 0.0001). The rate of in-hospital death for invasive ventilation recipients was 22.95%, 12.87% for supplemental oxygen recipients, and 7.41% for those who received neither (p = 0.0004). A sensitivity analysis of the 770 patients less than 80 years old revealed a lower, but similar mortality trend (18.02%, 8.10%, 5.23%; p = 0.0008) among the 14.42%, 65.71%, and 19.87% of patients treated with mechanical ventilation, supplemental oxygen only, or neither. Overall, invasive ventilation recipients who died were significantly older than those who survived (median age: 68.5 yr [60-81.36 yr] vs 62.5 yr [55.52-71 yr]; p = 0.0145). CONCLUSIONS: Among patients hospitalized for coronavirus disease 2019, 13% received mechanical ventilation, which was associated with a mortality rate of 23%.

Clinical features of patients with type 2 diabetes with and without Covid-19: A case control study (CoViDiab I).

AIMS: To evaluate whether subjects with diabetes hospitalized for Coronavirus disease-19 (Covid-19) represent a subgroup of patients with high-risk clinical features compared to patients with diabetes without Covid-19. METHODS: In this case-control study 79 patients with type 2 diabetes out of 354 adults hospitalized for Covid-19 and 158 controls with type 2 diabetes but without Covid-19, matched for age and gender, were enrolled. Medical history and concomitant therapies were retrieved from medical charts and compared between cases and controls, controlling for confounders. RESULTS: Fully-adjusted multivariate logistic regression model showed that previous CVD history did not differ between patients with and without Covid-19 (odds ratio 1.40, 95% confidence interval [CI]: 0.59-3.32, p = 0.45). A higher prevalence of chronic obstructive pulmonary disease (COPD) (OR 3.72, 95%CI: 1.42-9.72, p = 0.007) and of chronic kidney disease (CKD) (OR 3.08, 95%CI: 1.18-8.06, p = 0.022) and a lower prevalence of ever smokers (OR 0.30, 95%CI: 0.13-0.67, p = 0.003), of users of lipid lowering agents (OR 0.26, 95%CI: 0.12-0.54, p < 0.001), and of anti-hypertensive drugs (OR 0.39, 95%CI: 0.16-0.93, p = 0.033) were found among cases. CONCLUSIONS: CVD prevalence does not differ between people with diabetes with and without Covid-19 requiring hospitalization. An increased prevalence of COPD and of CKD in Covid-19 patients with type 2 diabetes is suggested. These findings aid to clarify the relationship between underlying conditions and SARS-CoV-2 infection in the high-risk group of patients with diabetes.

Challenges in the Management of SARS-CoV2 Infection: The Role of Oral Bacteriotherapy as Complementary Therapeutic Strategy to Avoid the Progression of COVID-19.

Background: Gastrointestinal disorders are frequent in COVID-19 and SARS-CoV-2 has been hypothesized to impact on host microbial flora and gut inflammation, infecting intestinal epithelial cells. Since there are currently no coded therapies or guidelines for treatment of COVID-19, this study aimed to evaluate the possible role of a specific oral bacteriotherapy as complementary therapeutic strategy to avoid the progression of COVID-19. Methods: We provide a report of 70 patients positive for COVID-19, hospitalized between March 9th and April 4th, 2020. All the patients had fever, required non-invasive oxygen therapy and presented a CT lung involvement on imaging more than 50%. Forty-two patients received hydroxychloroquine, antibiotics, and tocilizumab, alone or in combination. A second group of 28 subjects received the same therapy added with oral bacteriotherapy, using a multistrain formulation. Results: The two cohorts of patients were comparable for age, sex, laboratory values, concomitant pathologies, and the modality of oxygen support. Within 72 h, nearly all patients treated with bacteriotherapy showed remission of diarrhea and other symptoms as compared to less than half of the not supplemented group. The estimated risk of developing respiratory failure was eight-fold lower in patients receiving oral bacteriotherapy. Both the prevalence of patients transferred to ICU and mortality were higher among the patients not treated with oral bacteriotherapy. Conclusions: A specific bacterial formulation showed a significant ameliorating impact on the clinical conditions of patients positive for SARS-CoV-2 infection. These results also stress the importance of the gut-lung axis in controlling the COVID-19 disease.

Nox2 activation in Covid-19.

Nox2 is responsible for artery dysfunction via production of reactive oxidant species. RNA viruses may activate Nox2, but it is unknown if this occurs in coronavirus 2019(Covid-19). Nox2 activation by soluble Nox2-derived peptide(sNox2-dp) was measured in patients hospitalized for Covid-19 (n = 182) and controls (n = 91). sNox2-dp values were higher in Covid-19 patients versus controls and in severe versus non severe Covid-19. Patients with thrombotic events(n = 35,19%) had higher sNox2-dp than thrombotic event-free ones. A logistic regression analysis showed that sNox2 and coronary heart disease predicted thrombotic events. Oxidative stress by Nox2 activation is associated severe disease and thrombotic events in Covid-19 patients.

Chest CT score in COVID-19 patients: correlation with disease severity and short-term prognosis.

OBJECTIVES: To correlate a CT-based semi-quantitative score of pulmonary involvement in COVID-19 pneumonia with clinical staging of disease and laboratory findings. We also aimed to investigate whether CT findings may be predictive of patients' outcome. METHODS: From March 6 to March 22, 2020, 130 symptomatic SARS-CoV-2 patients were enrolled for this single-center analysis and chest CT examinations were retrospectively evaluated. A semi-quantitative CT score was calculated based on the extent of lobar involvement (0:0%; 1, < 5%; 2:5-25%; 3:26-50%; 4:51-75%; 5, > 75%; range 0-5; global score 0-25). Data were matched with clinical stages and laboratory findings. Survival curves and univariate and multivariate analyses were performed to evaluate the role of CT score as a predictor of patients' outcome. RESULTS: Ground glass opacities were predominant in early-phase (≤ 7 days since symptoms' onset), while crazy-paving pattern, consolidation, and fibrosis characterized late-phase disease (> 7 days). CT score was significantly higher in critical and severe than in mild stage (p < 0.0001), and among late-phase than early-phase patients (p < 0.0001). CT score was significantly correlated with CRP (p < 0.0001, r = 0.6204) and D-dimer (p < 0.0001, r = 0.6625) levels. A CT score of ≥ 18 was associated with an increased mortality risk and was found to be predictive of death both in univariate (HR, 8.33; 95% CI, 3.19-21.73; p < 0.0001) and multivariate analysis (HR, 3.74; 95% CI, 1.10-12.77; p = 0.0348). CONCLUSIONS: Our preliminary data suggest the potential role of CT score for predicting the outcome of SARS-CoV-2 patients. CT score is highly correlated with laboratory findings and disease severity and might be beneficial to speed-up diagnostic workflow in symptomatic cases. KEY POINTS: • CT score is positively correlated with age, inflammatory biomarkers, severity of clinical categories, and disease phases. • A CT score ≥ 18 has shown to be highly predictive of patient's mortality in short-term follow-up. • Our multivariate analysis demonstrated that CT parenchymal assessment may more accurately reflect short-term outcome, providing a direct visualization of anatomic injury compared with non-specific inflammatory biomarkers.