Risk Factors Associated with Mortality among Mechanically Ventilated Patients with Coronavirus Disease 2019 Pneumonia: A Multicenter Cohort Study in Japan (J-RECOVER Study).

Objective Mortality analyses of patients with coronavirus disease 2019 (COVID-19) requiring invasive mechanical ventilation in Japan are limited. The present study therefore determined the risk factors for mortality in patients with COVID-19 requiring invasive mechanical ventilation. Methods This retrospective cohort study used the dataset from the Japanese multicenter research of COVID-19 by assembling real-word data (J-RECOVER) study that was conducted between January 1 and September 31, 2020. Independent risk factors associated with in-hospital mortality were evaluated using a multivariate logistic regression analysis. Kaplan-Meier estimates of the survival were calculated for different age groups. A subgroup analysis was performed to assess differences in survival rates according to additional risk factors, including an older age and chronic pulmonary disease. Patients A total of 561 patients were eligible. The median age was 67 (interquartile range: 56-75) years old, 442 (78.8%) were men, and 151 (26.9%) died in the hospital. Results Age, chronic pulmonary disease, and renal disease were significantly associated with in-hospital mortality. Compared with patients 18-54 years old, the adjusted odds ratios of patients 55-64, 65-74, and 75-94 years old were 3.34 (95% CI, 1.34-8.31), 7.07 (95% CI, 3.05-16.40), and 18.43 (95% CI, 7.94-42.78), respectively. Conclusion Age, chronic pulmonary disease, and renal disease were independently associated with mortality in patients with COVID-19 requiring invasive mechanical ventilation, and age was the most decisive indicator of a poor prognosis. Our results may aid in formulating treatment strategies and allocating healthcare resources.

Mortality of Mechanically Ventilated COVID-19 Patients in Traditional versus Expanded Intensive Care Units in New York.

Rationale: During the first wave of the coronavirus disease (COVID-19) pandemic in New York City, the number of mechanically ventilated COVID-19 patients rapidly surpassed the capacity of traditional intensive care units (ICUs), resulting in health systems utilizing other areas as expanded ICUs to provide critical care. Objectives: To evaluate the mortality of patients admitted to expanded ICUs compared with those admitted to traditional ICUs. Methods: Multicenter, retrospective, cohort study of mechanically ventilated patients with COVID-19 admitted to the ICUs at 11 Northwell Health hospitals in the greater New York City area between March 1, 2020 and April 30, 2020. Primary outcome was in-hospital mortality up to 28 days after intubation of COVID-19 patients. Results: Among 1,966 mechanically ventilated patients with COVID-19, 1,198 (61%) died within 28 days after intubation, 46 (2%) were transferred to other hospitals outside of the Northwell Health system, 722 (37%) survived in the hospital until 28 days or were discharged after recovery. The risk of mortality of mechanically ventilated patients admitted to expanded ICUs was not different from those admitted to traditional ICUs (hazard ratio [HR], 1.07; 95% confidence interval [CI], 0.95-1.20; P = 0.28), while hospital occupancy for critically ill patients itself was associated with increased risk of mortality (HR, 1.28; 95% CI, 1.12-1.45; P < 0.001). Conclusions: Although increased hospital occupancy for critically ill patients itself was associated with increased mortality, the risk of 28-day in-hospital mortality of mechanically ventilated patients with COVID-19 who were admitted to expanded ICUs was not different from those admitted to traditional ICUs.

Histological findings of tracheal samples from COVID-19 positive critically ill mechanically ventilated patients.

OBJECTIVES: This study examines the histological findings of tracheal tissue samples obtained from COVID-19 positive mechanically ventilated patients, to assess the degree of tracheal inflammation/ulceration present. DESIGN AND PARTICIPANTS: Retrospective single-centre observational cohort study. All patients admitted to Adult Intensive Care Unit (AICU) with COVID-19 infection, requiring mechanical ventilation and surgical tracheostomy between 1 April and 1 May 2020, were included (Group 1). Tracheal windows excised at tracheostomy underwent histological analysis. Comparison was made with: tracheal windows from COVID-19 positive AICU ventilated patients admitted between 1 January and 1 March 2021 (Group 2); tracheal windows from COVID-19 negative AICU ventilated patients (Group 3); and, tracheal autopsy samples from COVID-19 positive patients that died without undergoing prolonged mechanical ventilation (Group 4). RESULTS: Group 1 demonstrated mild/moderate inflammation (tracheitis) in nearly all samples (15/16, 93.8%), with infrequent micro-ulceration (2/16, 12.5%). Group 2 demonstrated similar mild/moderate inflammation in all samples (17/17, 100%), with no ulceration. Histological findings of Groups 1 and 2 COVID-19 positive patients were similar to Group 3 COVID-19 negative patients, which demonstrated mild/moderate inflammation (5/5, 100%), with uncommon superficial erosion (1/5, 20%). Group 4 demonstrated mild chronic inflammation or no significant inflammation, with uncommon micro-ulceration (1/4, 25%). CONCLUSIONS: Severe tracheal inflammation was not demonstrated in mechanically ventilated COVID-19 positive patients at the level of the second/third tracheal rings, at the stage of disease patients underwent tracheostomy. Histological findings were similar between mechanically ventilated COVID-19 positive and negative patients. Tracheal ulceration may be a feature of early or severe COVID-19 disease.

Dynamics of SARS-CoV2 Infection and Multi-Drug Resistant Bacteria Superinfection in Patients With Assisted Mechanical Ventilation.

Objective: To investigate the presence of bacteria and fungi in bronchial aspirate (BA) samples from 43 mechanically ventilated patients with severe COVID-19 disease. Methods: Detection of SARS-CoV-2 was performed using Allplex 2019-nCoV assay kits. Isolation and characterisation of bacteria and fungi were carried out in BA specimens treated with 1X dithiothreitol 1% for 30 min at room temperature, using standard culture procedures. Results: Bacterial and/or fungal superinfection was detected in 25 out of 43 mechanically ventilated patients, generally after 7 days of hospitalisation in an intensive care unit (ICU). Microbial colonisation (colony forming units (CFU) <1000 colonies/ml) in BA samples was observed in 11 out of 43 patients, whereas only 7 patients did not show any signs of bacterial or fungal growth. Pseudomonas aeruginosa was identified in 17 patients. Interestingly, 11 out of these 17 isolates also showed carbapenem resistance. The molecular analysis demonstrated that resistance to carbapenems was primarily related to OprD mutation or deletion. Klebsiella pneumoniae was the second most isolated pathogen found in 13 samples, of which 8 were carbapenemase-producer strains. Conclusion: These data demonstrate the detection of bacterial superinfection and antimicrobial resistance in severe SARS-CoV-2-infected patients and suggest that bacteria may play an important role in COVID-19 evolution. A prospective study is needed to verify the incidence of bacterial and fungal infections and their influence on the health outcomes of COVID-19 patients.

Timing of Tracheostomy for Prolonged Respiratory Wean in Critically Ill Coronavirus Disease 2019 Patients: A Machine Learning Approach.

OBJECTIVES: To propose the optimal timing to consider tracheostomy insertion for weaning of mechanically ventilated patients recovering from coronavirus disease 2019 pneumonia. We investigated the relationship between duration of mechanical ventilation prior to tracheostomy insertion and in-hospital mortality. In addition, we present a machine learning approach to facilitate decision-making. DESIGN: Prospective cohort study. SETTING: Guy's & St Thomas' Hospital, London, United Kingdom. PATIENTS: Consecutive patients admitted with acute respiratory failure secondary to coronavirus disease 2019 requiring mechanical ventilation between March 3, 2020, and May 5, 2020. INTERVENTIONS: Baseline characteristics and temporal trends in markers of disease severity were prospectively recorded. Tracheostomy was performed for anticipated prolonged ventilatory wean when levels of respiratory support were favorable. Decision tree was constructed using C4.5 algorithm, and its classification performance has been evaluated by a leave-one-out cross-validation technique. MEASUREMENTS AND MAIN RESULTS: One-hundred seventy-six patients required mechanical ventilation for acute respiratory failure, of which 87 patients (49.4%) underwent tracheostomy. We identified that optimal timing for tracheostomy insertion is between day 13 and day 17. Presence of fibrosis on CT scan (odds ratio, 13.26; 95% CI [3.61-48.91]; p ≤ 0.0001) and Pao2:Fio2 ratio (odds ratio, 0.98; 95% CI [0.95-0.99]; p = 0.008) were independently associated with tracheostomy insertion. Cox multiple regression analysis showed that chronic obstructive pulmonary disease (hazard ratio, 6.56; 95% CI [1.04-41.59]; p = 0.046), ischemic heart disease (hazard ratio, 4.62; 95% CI [1.19-17.87]; p = 0.027), positive end-expiratory pressure (hazard ratio, 1.26; 95% CI [1.02-1.57]; p = 0.034), Pao2:Fio2 ratio (hazard ratio, 0.98; 95% CI [0.97-0.99]; p = 0.003), and C-reactive protein (hazard ratio, 1.01; 95% CI [1-1.01]; p = 0.005) were independent late predictors of in-hospital mortality. CONCLUSIONS: We propose that the optimal window for consideration of tracheostomy for ventilatory weaning is between day 13 and 17. Late predictors of mortality may serve as adverse factors when considering tracheostomy, and our decision tree provides a degree of decision support for clinicians.

Two mechanically ventilated cases of COVID-19 successfully managed with a sequential ventilation weaning protocol: Two case reports.

BACKGROUND: Patients with critical coronavirus disease 2019 (COVID-19), characterized by respiratory failure requiring mechanical ventilation (MV), are at high risk of mortality. An effective and practical MV weaning protocol is needed for these fragile cases. CASE SUMMARY: Here, we present two critical COVID-19 patients who presented with fever, cough and fatigue. COVID-19 diagnosis was confirmed based on blood cell counts, chest computed tomography (CT) imaging, and nuclei acid test results. To address the patients' respiratory failure, they first received noninvasive ventilation (NIV). When their condition did not improve after 2 h of NIV, each patient was advanced to MV [tidal volume (Vt), 6 mL/kg ideal body weight (IBW); 8-10 cmH2O of positive end-expiratory pressure; respiratory rate, 20 breaths/min; and 40%-80% FiO2] with prone positioning for 12 h/day for the first 5 d of MV. Extensive infection control measures were conducted to minimize morbidity, and pharmacotherapy consisting of an antiviral, immune-enhancer, and thrombosis prophylactic was administered in both cases. Upon resolution of lung changes evidenced by CT, the patients were sequentially weaned using a weaning screening test, spontaneous breathing test, and airbag leak test. After withdrawal of MV, the patients were transitioned through NIV and high-flow nasal cannula oxygen support. Both patients recovered well. CONCLUSION: A MV protocol attentive to intubation/extubation timing, prone positioning early in MV, infection control, and sequential withdrawal of respiratory support, may be an effective regimen for patients with critical COVID-19.