Although Acute Respiratory Distress Syndrome Research Articles

Update on COVID-19: A teleconference with the Paediatric Virology Study Group (Review).

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted to humans mainly via contact and droplet transmission and its entry into cells is mediated by the efficient binding of the spike (S) viral protein with the angiotensin converting enzyme-2 (ACE2) receptors. Although acute respiratory distress syndrome (ARDS) caused by SARS-CoV-2 fulfills the criteria of the Berlin definition, in a considerable proportion of patients with COVID-19, there is a dissociation between their relatively well-preserved lung mechanics and the severity of hypoxaemia. The extent of pneumococcal related morbidity and mortality is largely unknown. Respiratory comorbidities that increase the risk of severe disease and mortality due to SARS-CoV-2 include chronic obstructive pulmonary disease, asthma, bronchiectasis and fibrotic interstitial lung diseases, regardless of aetiology. Pneumococcal and seasonal influenza vaccinations are useful in preventing a substantial burden of mortality in high-risk populations, while general quarantine and social distancing can reduce the infiltration of the virus within the community. To date, several therapeutic agents have been studied or are currently examined, such as hydroxychloroquine, chloroquine, ritonavir/lopinavir, remdesivir, colchicines and interleukin-6 inhibitors. However, the usage of most of these into clinical practice was not based on randomised clinical trials and their results should be viewed with extreme caution; remdesivir seems to be the more promising option. Rigorous efforts are under way for the development of a safe and successful vaccine against SARS-CoV-2.

A case of toxic epidermal necrolysis with refractory acute respiratory distress syndrome

Toxic epidermal necrolysis (TEN) is a life-threatening cutaneous reaction with several complications. Although acute respiratory distress syndrome (ARDS) is rare, it can cause rapid and potentially fatal pulmonary dysfunction. Here, we present a case of TEN with ARDS attributed to acetaminophen. Toxic epidermal necrolysis (TEN) is a life-threatening cutaneous reaction with several complications. Although acute respiratory distress syndrome (ARDS) is rare, it can cause rapid and potentially fatal pulmonary dysfunction. Here, we present a case of TEN with ARDS attributed to acetaminophen. A 49-year-old woman with cerebral palsy was admitted to our hospital with a high fever and erythema of the face and trunk that developed 1 day earlier. She took acetaminophen twice at 4 and 1 day before admission. The erosion covered approximately 30% of the body surface area, and hemorrhagic erosions were observed on the lips (Figure 1A). TEN was diagnosed, with a severity-of-illness score (SCORTEN) of 3. Chest computed tomography (CT) revealed a bilateral infiltrative shadow in the lower lung fields (Figure 1B). Aspiration pneumonia was diagnosed. All medications were discontinued, and methylprednisolone pulse therapy (steroid pulse; 1000 mg/d for 3 days) was administered with antibiotics. On Day 2, she developed acute-onset dyspnea (SpO2: 70%-80%). Chest CT revealed spreading of the bilateral diffuse infiltrative shadow (Figure 1C). ARDS induced by TEN was diagnosed, and mechanical ventilation was initiated. Intravenous immunoglobulin therapy (IVIg; 400 mg/kg/d for 5 days) was administered after steroid pulse therapy, leading to rapid improvements in the skin and mucosal involvement. The prednisolone dosage was tapered to 30 mg/d, and re-epithelialization was completed on Day 19. Nevertheless, the ARDS responded poorly, and steroid pulse therapy was repeated on Days 19-21. Thereafter, the chest shadow and dyspnea gradually improved, and prednisolone was slowly tapered to 5 mg/d on Day 100. However, she developed an ARDS relapse a few days later and received steroid pulse therapy. The chest CT findings improved, although she could not be weaned from mechanical ventilation upon discharge at Day 150. A drug-induced lymphocyte stimulation test was positive for acetaminophen (stimulation index: 803%), and a patch test was negative. Reports describe an approximate respiratory complication rate of 40% during the acute phase of SJS/TEN.1 Prost et al reported that approximately 25% of SJS/TEN patients required mechanical ventilation (MV); of these cases, 57% had a fatal outcome.2 Lebargy et al reported that dyspnea, hypoxia, increased bronchial secretions, and normal chest X-rays within the first 3 days of illness indicated early bronchial involvement.3 To date, however, few case reports have described the features of SJS/TEN with ARDS. Three of 138 patients with SJS/TEN who were treated at our hospitals from 2000 to 2019 developed ARDS, of whom two (including the present case) survived. The third and fatal case did not begin treatment until more than 1 week postonset. Evidence regarding the effective treatment of pulmonary complications with SJS/TEN is lacking. Although antibiotics and steroids are commonly used,1 the effectiveness of systemic steroid therapy for ARDS remains controversial; some studies reported effectiveness,4, 5 while others reported no survival benefit.6, 7 Moreover, steroid-induced infections tend to worsen prognosis. We conclude that steroid initiation promptly after onset, followed by IVIg, may have contributed to our patient's survival. Additional case studies are needed to support future treatment development. The authors declare no conflict of interest.

Epidemiological and Clinical Profiles of Patients with Acute Respiratory Distress Syndrome Admitted to Medical Intensive Care in Qatar: A Retrospective Analysis of the Data Registry for the Year 2015.

Background: Although acute respiratory distress syndrome (ARDS) is a common reason for admission to intensive care units, limited information is available about the epidemiological and clinical characteristics of these patients in Middle Eastern countries. Qatar is a high per capita income country with a large multinational expatriate population. Hamad General Hospital is our main tertiary referral center with the largest medical intensive care unit (MICU). Method: A retrospective cross-sectional study was conducted to extract data from the MICU registry for 101 patients aged >14 years who were admitted with ARDS from January 2015 to December 2015. Results: In 2015, a total of 101 (14.8%) of 682 patients admitted to MICU were diagnosed with ARDS. Males comprised 71.3% and females 28.7%. The mean age of the study population was 44.96 ± 17.97 years. Community-acquired bacterial and viral pneumonia were the most common reasons for ARDS. Crude mortality rate was 35%. The mean age of survivors was 42.09 ± 13.58 years compared with 50.36 ± 16.84 years of non-survivors (p = 0.008). Mortality was associated with increasing age, the Acute Physiologic Assessment and Chronic Health Evaluation II severity score, lower P/F ratio, higher Murray's score, higher PCO2, lower pH, and circulatory support with vasopressors. Preexisting comorbidities did not contribute to high mortality. No difference in mortality was noted with higher versus lower positive end expiratory pressure. The prone position was used in 8% of the cases. Twenty-seven (27%) patients had undergone salvage therapy with extracorporeal membrane oxygenation (ECMO) that resulted in a survival rate of 44%. ARDS was associated with acute renal failure requiring dialysis in 28.7% of the cases, pneumothoraces in 4%, ventilator-associated pneumonia in 7.9%, and central line-associated bloodstream infection in 2%. ARDS led to a prolonged length of stay compared with the average length of stay in MICU. Conclusion: Community-acquired bacterial and viral pneumonia were the most common causes of ARDS at our center. Critical care outcome correlated with the severity of the disease. ECMO was used as salvage therapy in our center.

Clinical differences between pulmonary and extrapulmonary acute respiratory distress syndrome: a retrospective cohort study of prospectively collected data in Japan.

Although acute respiratory distress syndrome (ARDS) reportedly shows various clinical phenotypes with different risk and prognostic factors, few studies have assessed the clinical features and prognosis of pulmonary and extrapulmonary ARDS. The aim of the present study was to investigate clinical differences between pulmonary and extrapulmonary ARDS. In total, 200 patients who met the Berlin criteria and were diagnosed with ARDS between October 2004 and September 2017 were included. We classified the patients into pulmonary and extrapulmonary ARDS groups. Both groups were assessed for 60-day mortality, duration of ventilation, and other clinical features. There were 150 and 50 patients in the pulmonary and extrapulmonary ARDS groups, respectively. The two groups showed no significant differences in any assessment parameters except the serum lactate dehydrogenase (LDH) level, which was higher in the extrapulmonary ARDS group (P=0.01). After adjustment for potentially confounding covariates, there were no significant differences in 60-day mortality (P=0.99) and the duration of ventilation (P=0.45) between the two groups. Mortality was significantly associated with the disseminated intravascular coagulation (DIC) score, high-resolution computed tomography (HRCT) score, and serum LDH level in the pulmonary ARDS group and the DIC score and HRCT score in the extrapulmonary ARDS group. Pulmonary and extrapulmonary ARDS may be comparable in terms of the prognosis and duration of ventilation. DIC and HRCT scores may be common clinical predictors of mortality with ARDS.

Practice of diagnosis and management of acute respiratory distress syndrome in mainland China: a cross-sectional study.

Although acute respiratory distress syndrome (ARDS) has been recognized for more than 50 years, limited information exists about the incidence and management of ARDS in mainland China. To evaluate the potential for improvement in management of patients with ARDS, this study was designed to describe the incidence and management of ARDS in mainland China. National prospective multicenter observational study over one month (August 31st to September 30th, 2012) of all patients who fulfilled the Berlin or American European Consensus Conference (AECC) definition of ARDS in 20 intensive care units, with data collection related to the management of ARDS, patient characteristics and outcomes. Of the 1,814 patients admitted during the enrollment period, 149 (8.2%) and 147 (8.1%) patients were diagnosed by AECC and Berlin definition, respectively. Lung protective strategy with low tidal volume (Vt) (≤8 mL/kg) and limitation of the plateau pressure (Pplat) (≤30 cmH2O) was performed in 75.2% patients. And, 36%, 21.1% and 4.1% patients with severe, moderate and mild ARDS had the driving pressure more than 14 cmH2O (P<0.05). Pplat and driving pressure increased significantly in patients with a higher degree of ARDS severity (P=0.002 and P<0.001, respectively), but Vt were comparable in the three groups (P>0.05). In severe ARDS, patient median positive end expiratory pressure (PEEP) was 10.0 (8.0-11.3) cmH2O and median FiO2 was 90%. A recruitment maneuver was performed in 35.5% of the patients, and 8.7% of patients with severe ARDS received prone position. Overall hospital mortality was 34.0%. Hospital mortality was 21.8% for mild, 31.1% for moderate, and 60.0% for patients with severe ARDS (P=0.004). Despite general acceptance of low Vt and limited Pplat, high driving pressure, low PEEP and low use of adjunctive measures may still be a concern in mainland China, especially in patients with severe ARDS. ClinicalTrials.gov NCT01666834; date of registration release: August 14th 2012.

Constitutively Expressed IFITM3 Protein in Human Endothelial Cells Poses an Early Infection Block to Human Influenza Viruses.

Avian influenza viruses, including H5N1 and H7N9, have been associated with severe respiratory disease and fatal outcomes in humans. Although acute respiratory distress syndrome (ARDS) and progressive pulmonary endothelial damage are known to be present during severe human infections, the role of pulmonary endothelial cells in the pathogenesis of avian influenza virus infections is largely unknown. By comparing human seasonal influenza strains to avian influenza viruses, we provide greater insight into the interaction of influenza virus with human pulmonary endothelial cells. We show that human influenza virus infection is blocked during the early stages of virus entry, which is likely due to the relatively high expression of the host antiviral factors IFITMs (interferon-induced transmembrane proteins) located in membrane-bound compartments inside cells. Overall, this study provides a mechanism by which human endothelial cells limit replication of human influenza virus strains, whereas avian influenza viruses overcome these restriction factors in this cell type.

Recruitment maneuver for escape oxygenation in acute respiratory distress syndrome

Introduction: Although acute respiratory distress syndrome (ARDS) has been focus of attention of all intensive care practitioners for decades, many issues regarding mechanical ventilation, the cornerstone of the treatment, have not yet been clarified. Recruitment maneuver (RM) has been used within initial 7 days of treatment, in order to expand collapsed alveoli, determine the optimum values of PEEP and improve oxygenation. The intervention is not standardized; it is still not clear if various protocols have any difference in clinical effects and outcome. However, since hypoxemia in patients with ARDS may be very severe and life threatening, RM can be used to improve oxygenation. Case report: Here, we present the patient suffering from aortic dissection Type 3 (DeBakey classification) and severe ARDS due to aspiration of gastric contents. The patient was ventilated with volume controlled mechanical ventilation, with low tidal volumes and different values of PEEP. In order to improve oxygenation (rescue oxygenation) and to determine the optimal value of PEEP, staircase RM has been applied successfully. Improved oxygenation during critical phases of illness may have contributed to the overall favorable outcome. Conclusion: In patients with ARDS, various interventions may be used to correct severe hypoxemia. Staircase recruitment maneuver may be used as a part of mechanical ventilation strategy, in order to improve oxygenation and define optimal PEEP for selected patients.

High-frequency oscillatory ventilation in RSV bronchiolitis patients

Respiratory syncytial virus (RSV) is the leading cause of bronchiolitis and pneumonia in infants and young children (1–3). Prematurity, bronchopulmonary dysplasia (BPD), congenital heart disease and immune disorders are wellknown risk factors associated with significant morbidity and mortality (4–7). These children may need prolonged hospitalization, mechanical ventilation and even extracorporeal membrane oxygenation (ECMO) when conventional mechanical ventilation (CMV) fails (8–11). RSV-induced respiratory failure is most often due to obstructive lung disease, although acute respiratory distress syndrome (ARDS) secondary to RSV infection has been described (3). High-frequency oscillatory ventilation (HFOV) may significantly improve oxygenation and outcome in pre-term infants with respiratory distress syndrome (12–16) and beyond the neonatal period in patients with a variety of diffuse alveolar diseases, such as ARDS and pneumonia (17–21). However, in small airway disease HFOV is considered potentially hazardous because of the risk of air trapping (17,22). Therefore, in clinical trials of HFOV, patients with small airway disease, including bronchiolitis, are generally excluded from study (18). We have found only one case report of HFOV to improve gas exchange and to avoid ECMO in a bronchiolitis patient (23). We report five patients with small airway disease caused by RSV bronchiolitis who were treated with HFOV as a rescue therapy after deterioration on CMV.