IntroductionAcute respiratory distress syndrome (ARDS) is a type of acute respiratory failure characterised by non-cardiac pulmonary oedema caused by various underlying conditions. ARDS is often pathologically characterised by diffuse alveolar damage, and its pathological findings have been reported to be associated with prognosis, although the adverse effects of lung biopsies to obtain pathological findings are still unclear. The purpose of this systematic review and meta-analysis is to reveal the safety and feasibility of lung biopsy in the diagnosis of ARDS.Methods and analysisWe will include studies that were published in MEDLINE and Cochrane Central Register of Controlled Trials until 1 June 2020. We will include the reports for critically ill patients in an intensive care unit or emergency department who undergo lung biopsy and require a mechanical ventilation. Two review authors will independently scan titles and abstracts of all identified studies. Furthermore, these two authors will read and assess the full text of study reports to identify trials that appeared broadly to address the subject of the review. We will perform a risk of bias assessment using the McMaster Quality Assessment Scale of Harms.Ethics and disseminationThis study will be based on the published data, therefore, it does not require ethical approval. The final results of the study will be published in a peer-reviewed journal.Trial registration numberUMIN000040650.
Pathological findings of COVID-19 associated with acute respiratory distress syndrome