Trends in survival during the pandemic in patients with critical COVID-19 receiving mechanical ventilation with or without ECMO: analysis of the Japanese national registry data.

BACKGROUND: The survival rate of patients with critical coronavirus disease-19 (COVID-19) over time is inconsistent in different settings. In Japan, a national database was organized to monitor and share the patient generation across the country in an immediate response to the COVID-19 pandemic. This study aimed to evaluate changes in survival over time and the prognostic factors in critical COVID-19 patients receiving mechanical ventilation with/without extracorporeal membrane oxygenation (ECMO) using the largest database in Japan. METHODS: This is a prospective observational cohort study of patients admitted to intensive care units in Japan with fatal COVID-19 pneumonia receiving mechanical ventilation and/or ECMO. We developed a prospective nationwide registry covering > 80% of intensive care units in Japan, and analyzed the association between patients' backgrounds, institutional ECMO experience, and timing of treatment initiation and prognosis between February 2020 and November 2021. Prognostic factors were evaluated by Kaplan-Meier analysis and Cox proportional hazards analysis. RESULTS: A total of 9418 patients were ventilated, of whom 1214 (13%) received ECMO. The overall survival rate for ventilated patients was 79%, 65% for those receiving ECMO. There have been five outbreaks in Japan to date. The survival rate of ventilated patients increased from 76% in the first outbreak to 84% in the fifth outbreak (p < 0.001). The survival rate of ECMO patients remained unchanged at 60-68% from the first to fifth outbreaks (p = 0.084). Age of ≥ 59 (hazard ratio [HR] 2.17; 95% confidence interval [CI] 1.76-2.68), ventilator days of ≥ 3 before starting ECMO (HR 1.91; 95% CI 1.57-2.32), and institutional ECMO experiences of ≥ 11 (HR 0.70; 95% CI 0.58-0.85) were independent prognostic factors for ECMO. CONCLUSIONS: During five COVID-19 outbreaks in Japan, the survival rate of ventilated patients tended to have gradually improved, and that of ECMO patients did not deteriorate. Older age, longer ventilator days before starting ECMO, and fewer institutional ECMO experiences may be independent prognostic factors for critical COVID-19 patients receiving ECMO.

Safety and harms of bronchoalveolar lavage for acute respiratory failure: A systematic review and meta-analysis.

BACKGROUND: This review aimed to investigate whether bronchoalveolar lavage (BAL) is safe in patients with severe acute respiratory failure (ARF). METHODS: We searched the MEDLINE, CENTRAL, and other databases up to June 2, 2021 for studies that examined BAL for severe ARF. We included all cohort studies and randomized or non-randomized trials, while we excluded case-control studies, case reports, and case series. We evaluated the quality of the evidence using the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS: We included 17 studies (1085 patients) in the meta-analysis. The integrated frequency of death was 0.000% (95% confidence interval [CI]: 0.000-0.045%, I2 = 0.0%). The pooled risk of severe complications of respiratory system, cardiovascular system, and major bleeding was 1.32% (95% CI: 0.000-4.41%, I2 = 84.8%), 0.040% (95% CI: 0.000-0.71%, I2 = 9.3%), and 0.000% (95% CI: 0.000-0.27%, I2 = 0.0%), respectively. In the subgroup analysis with mechanical ventilation during BAL, there were few severe complications of the respiratory system (3/717 patients in 13 studies) and almost no heterogeneity (I2 = 0.0%). CONCLUSIONS: Our study suggests that severe complications of BAL for severe ARF are probably rare, particularly in patients receiving mechanical ventilation. After considering the risks and benefits, it would be worthwhile to consider performing BAL in patients with severe ARF of unknown etiology to pursue its cause. TRIAL REGISTRATION: The protocol was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN000040600).

Establishment of a Disaster Management-like System for COVID-19 Patients Requiring Veno-Venous Extracorporeal Membrane Oxygenation in Japan.

The coronavirus disease 2019 (COVID-19) pandemic has increased the number of patients who require extracorporeal membrane oxygenation (ECMO). To manage the demand for ECMO, Japan ECMOnet for COVID-19 was developed as a "disaster management-like system", utilizing the Cross ICU Searchable Information System (CRISIS) database. This study investigated the effect of the establishment of this disaster management-like system in Japan. This was a nationwide retrospective observational study conducted from 1 February to 31 July in 2020. A total of 187 patients with COVID-19 who received ECMO were included. The median age was 60 years (interquartile range, 53-68), the median length of ventilatory support before ECMO was 3 days (1-5), and the median PaO2 to FiO2 ratio at ECMO initiation was 86 (71.3-101.5). During the study period, 165 telephone consultations were conducted, including general questions about ECMO. Among them, 44 concerned patients who were already on ECMO or who ultimately received ECMO. Further coordination, including transport and ECMO physician dispatch, was provided for 23 cases. Overall, 125/187 (66.8%) patients were successfully weaned from ECMO. This study demonstrated that Japan has achieved favorable survival outcomes for patients with COVID-19 who received ECMO with a disaster management-like system. Further research on the causes of these outcomes is needed.