Background Although rare, cardiac arrest during pregnancy is the leading cause of maternal death. Recently, its incidence has been increasing worldwide because more pregnant women have risk factors. The provision of early, high-quality cardiopulmonary resuscitation (CPR) plays a major role in the increased likelihood of survival; therefore, it is important for clinicians to know how to manage it. Due to the aortocaval compression caused by the gravid uterus, clinical guidelines often emphasise the importance of maternal positioning during CPR, but there has been little evidence regarding which position is most effective. Methods We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and OpenGrey (updated on April 3, 2021). We included clinical trials and observational studies with reported outcomes related to successful resuscitations. Results We included eight studies from the 1,490 screened. The eight studies were simulation-based, crossover trials that examine the quality of chest compressions. No data were available about the survival rates of mothers or foetuses/neonates. The meta-analyses showed that resuscitation of pregnant women in the 27°–30° left-lateral tilt position resulted in lower quality chest compressions. The difference is an 19% and 9% reduction in correct compression depth rate and correct hand position rate, respectively, compared with resuscitations in the supine position. Inexperienced clinicians find it difficult to perform chest compressions in the left-lateral tilt position. Conclusions Given that manual left uterine displacement allows the patient to remain supine, the resuscitation of women in the supine position using manual left uterine displacement should continue to be supported. Further research is needed to fill knowledge gaps regarding the effects of maternal positioning on clinical outcomes, such as survival rates following maternal cardiac arrest.

The perinatal resuscitation history in Japan is short, with the earliest efforts in the field of neonatology. In contrast, the standardization and dissemination of maternal resuscitation is lagging. With the establishment of the Maternal Death Reporting Project and the Maternal Death Case Review and Evaluation Committee in 2010, with the aim of reducing maternal deaths, the true situation of maternal deaths came to light. Subsequently, in 2015, the Japan Council for the Dissemination of Maternal Emergency Life Support Systems (J-CIMELS) was established to educate and disseminate simulations in maternal emergency care; training sessions on maternal resuscitation are now conducted in all prefectures. Since the launch of the project and council, the maternal mortality rate in Japan (especially due to obstetric critical hemorrhage) has gradually decreased. This has been probably achieved due to the tireless efforts of medical personnel involved in perinatal care, as well as the various activities conducted so far. However, there are no standardized guidelines for maternal resuscitation yet. Therefore, a committee was set up within the Japan Resuscitation Council to develop a maternal resuscitation protocol, and the Guidelines for Maternal Resuscitation 2020 was created in 2021. These guidelines are expected to make the use of high-quality resuscitation methods more widespread than ever before. This presentation will provide an overview of the Guidelines for Maternal Resuscitation 2020.