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Background The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021. Methods The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method. Results Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4–8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO2 (PaO2) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D), we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D), we suggest against routinely implementing NO inhalation therapy (GRADE 2C), and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D). Conclusions This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jsicm.org/publication/guideline.html). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Objective Pregnant women may develop disseminated intravascular coagulation (DIC), possibly resulting in massive maternal haemorrhage and perinatal death. The Japan guideline recommends use of antithrombin III (ATIII) for DIC in obstetrics; however, its effect remains uncertain. The present study aimed to investigate the effect of ATIII for DIC in obstetrics, using a national inpatient database in Japan. Design Nationwide observational study. Setting Japan. Population We used the Diagnosis Procedure Combination inpatient database to identify patients who delivered at hospital and were diagnosed with DIC from July 2010 to March 2018. Methods Propensity score matching analyses were performed to compare in‐hospital maternal mortality and hysterectomy during hospitalisation between users and non‐users of ATIII on the day of delivery. Main outcome measures In‐hospital mortality, hysterectomy. Results A total of 9920 patients were enrolled, including 4329 patients (44%) who used ATIII and 5511 patients (56%) who did not use ATIII. One‐to‐one propensity score matching created 3290 pairs. In‐hospital maternal mortality did not differ significantly between the propensity‐matched groups (0.3% in the ATIII group versus 0.5% in the control group; odds ratio 0.73; 95% CI 0.35–1.54). A significantly lower proportion of patients in the ATIII group, compared with those in the control group, underwent hysterectomy during hospitalisation (5.3% versus 8.7%; absolute risk difference −2.9%; 95% CI −4.2 to −1.6%). Conclusions Although the present study did not show a mortality‐reducing effect of ATIII for patients with DIC in obstetrics, it may have clinical benefit in terms of reducing the number of patients undergoing hysterectomy. Tweetable abstract This study did not show mortality‐reducing effect of antithrombin III for patients with DIC in obstetrics.

IntroductionSodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of antihyperglycaemic agents that promote urinary glucose excretion in the renal proximal tubule and have cardio-protective and renal-protective properties. However, there are several safety concerns related to increased risks of hypoglycaemic, urinary tract infections and ketoacidosis. Ketoacidosis is a potentially fatal complication that often presents as euglycaemic ketoacidosis during SGLT2 inhibitor treatment. Furthermore, invasive treatment and related surgical stress may increase the risk of ketogenesis. Therefore, this study aims to clarify the incidence of SGLT2 inhibitor-associated postoperative ketoacidosis (SAPKA) among patients who are receiving SGLT2 inhibitors and undergoing surgery under general anaesthesia.Methods and analysisThis multicentre, prospective, observational study will recruit 750 adult Japanese patients with diabetes who are receiving SGLT2 inhibitors and undergoing surgery under general anaesthesia. Urine samples will be collected on postoperative days 0, 1, 2 and 3. Blood gas analysis will be performed when urine ketone positivity is detected. The incidence of postoperative ketoacidosis will be identified based on urine ketone positivity and a blood pH of ≤7.3. The study will also collect data to identify risk factors for SAPKA.Ethics and disseminationThe study protocol has been approved by the ethics committee of Kyorin University (approval number: 785, 26 October 2020) and local ethical approval will be required at each participating centre. Study findings will be submitted to peer-reviewed journals and abstracts will be submitted to relevant national and international meetings.Trial registration numberUMIN000042795