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.

[Results of treatment of severe cases of COVID-19.]

COVID-19はウイルス感染を契機とした肺炎像である.重症度の程度は様々であるが,病状が進行するとARDS(Acute Respiratory Distress Syndrome)の状態となる.薬物療法では抗ウイルス薬投与とステロイドが現時点ではclassIとなっている.しかし,低酸素血症が増悪すると,人工呼吸器管理やECMO(Extracorporeal membrane oxygenation)管理が必要となる.各々の管理も通常管理ではなく,ARDSに準じた高度な管理方法が求められる.日本ECMO netがwebにて公開しているCRISIS(CRoss Icu Searchable Information System)データベースによると2020年5月31日の段階で人工呼吸器実施数が496名,離脱数が3,790名,死亡が1,048名となっている.またECMO実施数が54名,離脱数が421名,死亡数が220名となっている.このような未曾有のICU管理が多数出現する重症疾患に対して,日本ECMO netは,厚生労働省事業としてECMOチーム等養成研修事業,重症者治療搬送調整等支援事業を立ち上げ,重症治療のサポート業務の一旦を担っている.ECMOチーム等養成研修事業に関しては,COVID-19に適切な人工呼吸器管理およびECMO管理を行う講習会を全国47都道府県で実施した.重症者治療搬送調整等支援事業では,人工呼吸器管理に関しての追加支援やECMOセンターもしくはECMO実施施設への転院を行う際に適切な導入時期・導入場所の決定の支援を行った.COVID-19重症治療に関しては,単施設だけでは困難な場合があり,複数の施設の協力によって成り立つ場合もあり,より救命・社会復帰の可能性を高める.(著者抄録)

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.

Extracorporeal membrane oxygenation for COVID-19: a systematic review and meta-analysis.

BACKGROUND: There are several reports of extracorporeal membrane oxygenation (ECMO) use in patients with coronavirus disease 2019 (COVID-19) who develop severe acute respiratory distress syndrome (ARDS). We conducted a systematic review and meta-analysis to guide clinical decision-making and future research. METHODS: We searched MEDLINE, Embase, Cochrane and Scopus databases from 1 December 2019 to 10 January 2021 for observational studies or randomised clinical trials examining ECMO in adults with COVID-19 ARDS. We performed random-effects meta-analyses and meta-regression, assessed risk of bias using the Joanna Briggs Institute checklist and rated the certainty of evidence using the GRADE approach. Survival outcomes were presented as pooled proportions while continuous outcomes were presented as pooled means, both with corresponding 95% confidence intervals [CIs]. The primary outcome was in-hospital mortality. Secondary outcomes were duration of ECMO therapy and mechanical ventilation, weaning rate from ECMO and complications during ECMO. RESULTS: We included twenty-two observational studies with 1896 patients in the meta-analysis. Venovenous ECMO was the predominant mode used (98.6%). The pooled in-hospital mortality in COVID-19 patients (22 studies, 1896 patients) supported with ECMO was 37.1% (95% CI 32.3-42.0%, high certainty). Pooled mortality in the venovenous ECMO group was 35.7% (95% CI 30.7-40.7%, high certainty). Meta-regression found that age and ECMO duration were associated with increased mortality. Duration of ECMO support (18 studies, 1844 patients) was 15.1 days (95% CI 13.4-18.7). Weaning from ECMO (17 studies, 1412 patients) was accomplished in 67.6% (95% CI 50.5-82.7%) of patients. There were a total of 1583 ECMO complications reported (18 studies, 1721 patients) and renal complications were the most common. CONCLUSION: The majority of patients received venovenous ECMO support for COVID-19-related ARDS. In-hospital mortality in patients receiving ECMO support for COVID-19 was 37.1% during the first year of the pandemic, similar to those with non-COVID-19-related ARDS. Increasing age was a risk factor for death. Venovenous ECMO appears to be an effective intervention in selected patients with COVID-19-related ARDS. PROSPERO CRD42020192627.

Veno-venous extracorporeal membrane oxygenation and prone ventilation for therapeutic management of COVID-19.

BACKGROUND: The efficacy and safety of the combined use of veno-venous extracorporeal membrane oxygenation (ECMO) and prone ventilation are currently not known for coronavirus disease 2019 (COVID-19). CASE PRESENTATION: We report two cases in which the combination of veno-venous ECMO and prone ventilation for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia were successfully carried out. Both patients had developed severe respiratory failure due to SARS-CoV-2 pneumonia, thus requiring veno-venous ECMO. Prone ventilation was also administered safely. CONCLUSION: Oxygenation and lung compliance gradually improved during prone ventilation, and both patients were successfully extubated. For patients with severe SARS-CoV-2 pneumonia who require veno-venous ECMO, the use of prone ventilation could be beneficial, and should be considered.

Nationwide system to centralize decisions around ECMO use for severe COVID-19 pneumonia in Japan

Abstract The novel coronavirus disease 2019 (COVID-19) is spreading in Japan. The number of patients who need extracorporeal membranous oxygenation (ECMO) is expected to increase, however the clinical characteristics of the patients who require and will benefit from ECMO are unclear.